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Blue Helix
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How to make a _good_ magnetic stirrer for cheap 4
#26877787 - 08/13/20 01:24 AM (3 years, 5 months ago) |
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First, why would anyone even want a magnetic stirrer? If you don't have this and use the "swish daily" technique, the LC develops a lot less robustly. It's slower to develop and looks like snot rather than blobs. With a magnet stirrer you LCs will explode in the jar and look more like these:
 
Given the ridiculous price of magnetic stirrers for a lab I can certainly see why people seldom buy them. though. Of course, eBay has the cheapies direct from China, but I've tried them and they have a fatal flaw: they are using a PC fan motor with a resistor for speed control. That means they spin too fast on all settings.
The lowest I could dial mine down before it stopped was maybe 700 RPM. And even at that speed, the motor won't last long because it's not designed to do this! In other words, they are junk not worth $5, much less their $40 to $60 price tag! That's kind of expensive for a device that moves a magnet in a circle even if it did work right (which it doesn't).
What I'd like to do is go through the steps of making good one for about $20 or less (depends on how much stuff you have). First, let's list the parts, staring with the most expensive component ($14), the beautifully-built geared-down motor:
- 300 RPM @ 24V DC Gearhead motor from Amazon - we'll be using this gearhead motor to spin 150 to 200 RPM by using 9V to 12V. That's about the speed you want, not 300 RPM at 24V and definitely not 1000 RPM like PC fans and the junk ones on eBay. This is such a beautiful little motor I felt kind of bad just using it for this humble task since it can handle a lot of torque, but it has the right speed.
- A half-pint wide-mouth jar with 2 plastic lids. You should be using those to make my LC lids as I described here
- Narrow-mouth Kerr lid. This is kind of optional because if you think about it, almost anything could work, even and inch and a half of a Popsicle stick with a hole drilled in the middle for the shaft. I liked the narrom-mouth Kerr lid because the magnets stick to it without glue.
- Drill with some common-sized bits (you can sort of use whatever sizes are close to what you want) - can be hand drill or whatever
- Hot-glue gun
- Some duct or gaffers tape
- DC power box for either 9V to 12V DC is best. Don't worry about how much power the box can produce because I measured 2 watts at 9V (basically nothing). Here are two examples, but I'm sure you can either find one in some junk around your place (or a thrift store) or buy them even cheaper. -
eBay direct from China for less than $2 Through Amazon for $7
- Two small magnets. Neodymium is better but whatever would probably work (the dime is there for size comparison purpose only)

- Optional: Teflon stir bar. It's not shown here but I also stretch a piece of silicone rubber in the middle so it doesn't clink with the glass when spinning. Stir bars can be anything that can hold up in a pressure cooker, is between say 3/4" and 2 1/2" long, and is attracted to a magnet (use your imagination).
 Okay, so instead of write a lot of boring words, I am going to show you pictures and animations of mine already done, both fully assembled and apart.
First here is the unit fully assembled, the two lids (the full one and the one that has the shaft through it taped with duct tape) and running at the right speed for mixing an LC, which is around 100 RPM at 9V as shown. Notice how the magnet sweeps across the bottom rather than rotate in the middle? That's because of how I have my magnets inside, but I liked it that way because it does a better job of mixing the entire jar. I took the sound out, but its almost totally silent at 12V or less (I'd guess around 10db TOPS):

Now let's remove the tape, remove the top full plastic lid, and take a look inside. Notice the magnets on the half-pint narrow mouth lid? Those were not even glued because there was no need. You must make them opposite poles facing up. If you don't know what that mean, get out your Teflon magnet and make sure it sticks to them. Notice how the shaft had a dab of hot glue on it. :

And spinning (note: this doesn't have to spin perfectly. Just make it as good as you reasonably can):

And in the half-pint jar is the motor which had a dab of hot glue on top to make it stick to the lid. I had to bend the metal power tabs sideways for it to fit in the half-pint jar with the lid on. Also while one of those holes was in the lid to run the cord, the other was because I used a junk lid that I practiced making holes in since you cannot see it anyway:

And what about that power supply? Well anything from about 9V to 15V DC is fine. The motor and the DC power supply I used took only 2 watts at 9V according to my tester, which means it's like less than $2 to run the entire year if you did that. Most of that is simply a typical vampire load, though, so if you don't want that, buy the weakest power supply you can find :

Well, that's it! It's not adjustable, but if that is a big deal to you, get a variable voltage power supply. The motor can handle up to 24V which would turn it a bit too fast at 300 RPM, so I'd stick with 12V to 6V (lowest) for a good mycelium-growth RPM.
Edited by Blue Helix (08/14/20 12:08 AM)
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jcm4620
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Re: How to make a _good_ magnetic stirrer for cheap [Re: Blue Helix]
#26877848 - 08/13/20 03:33 AM (3 years, 5 months ago) |
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sweet if i ever go the lc route il be makin one
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Blue Helix
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Re: How to make a _good_ magnetic stirrer for cheap [Re: jcm4620]
#26877854 - 08/13/20 03:49 AM (3 years, 5 months ago) |
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Quote:
jcm4620 said: sweet if i ever go the lc route il be makin one
Yeah that motor I just got today because I wanted to make sure it would work (I had some weaker, more noisy ones). Well, the motor is way too good for this task, but hey, it was only $14 I guess.
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lovepotion
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Re: How to make a _good_ magnetic stirrer for cheap [Re: Blue Helix]
#26877868 - 08/13/20 04:23 AM (3 years, 5 months ago) |
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He's back! This looks 1000x more legit than the computer fan plates that are stopped with fingers
I like how you incorporate hot glue into your teks. A signature perhaps. Hot Blue Gun
-------------------- Staying Out to Lunch
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Blue Helix
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Re: How to make a _good_ magnetic stirrer for cheap [Re: lovepotion]
#26878735 - 08/13/20 02:38 PM (3 years, 5 months ago) |
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Quote:
lovepotion said: He's back! This looks 1000x more legit than the computer fan plates that are stopped with fingers
I like how you incorporate hot glue into your teks. A signature perhaps. Hot Blue Gun
The reason I use hot glue in small projects like this is because hot glue sticks to both metal and plastic well, isn't permanent, and still hardens fast. Those properties are what make it so valuable. When I was making this yesterday, I thought about some things that might go wrong (like say the glue dribbled down onto the motor's shaft and seized it) and, instead of using epoxy, I used hot glue just in case I had to backtrack. Of course, any place I used hot glue, you can probably use epoxy putty or epoxy glue--I have both--but if I want to use that motor later for say a multiple spinner version, then it might be super hard to remove the epoxy. I like to keep my options open for future projects.
Edited by Blue Helix (08/13/20 02:44 PM)
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verum subsequentis
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Re: How to make a _good_ magnetic stirrer for cheap [Re: Blue Helix] 1
#26878756 - 08/13/20 02:48 PM (3 years, 5 months ago) |
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What do you have against higher rpm? I personally love to spin the ever living shit out of the LC. I prefer thousands of tiny myc fragments to hundreds of little blobs. I find it spreads through the grain bag better without getting caught up in certain areas. Not that it makes a world of difference though.
Nice write up.
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Blue Helix
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Quote:
verum subsequentis said: What do you have against higher rpm? I personally love to spin the ever living shit out of the LC. I prefer thousands of tiny myc fragments to hundreds of little blobs. I find it spreads through the grain bag better without getting caught up in certain areas. Not that it makes a world of difference though.
Nice write up.
Good, question, and it's one that I wondered too since making a "spin the shit out of it" mag stirrer is trivial with a PC fan and two magnets. So why bother with slower (traditional lab) spin speed?
Well, if you stir the shit out of it--and I used to do that so I'm not knocking it here--all that happens is that you cannot tell mold contamination very well (you can still see bacterial though since that's just an LC that doesn't settle and is cloudy). I hear people bitching and moaning that they cannot spot contamination all the time with LCs. In fact, it's one of the reasons people won't try LCs even. I don't have that problem at all. The reason the myth exists that one cannot spot contamination is because they aren't spinning it at the right speed (usually way too fast) or at all (the swishing disaster).
But, still, if you like super fast RPMs and want to save about $7 or so, just glue two magnets on the blades of a PC fan (online they run all of $4 or so), get a box power supply around 9V, and sit the jar on the fan guard. That's what I used to do at least, until I realized you cannot spot simple contamination like that very well.
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Blue Helix
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Quote:
verum subsequentis said: What do you have against higher rpm? I personally love to spin the ever living shit out of the LC. I prefer thousands of tiny myc fragments to hundreds of little blobs. I find it spreads through the grain bag better without getting caught up in certain areas. Not that it makes a world of difference though.
Nice write up.
Adding a little more here: if you spin around 150 RPM, you can even tell the type of mycelium growing in there in terms of rhizomorphic, linear, etc. by looking carefully at the blobs. Spiky bigger blobs, for example, are a sign of rapid rhizomorpic grow. Again if you are swishing or spinning it crazy fast, you can't do that.
Also, if you are using the LC lids I describe, you can always give it a hearty shake right before the draw if you really think it helps it spread better. I have serious doubts about that, though.
Edited by Blue Helix (08/13/20 04:47 PM)
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greenmachine78
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Re: How to make a _good_ magnetic stirrer for cheap [Re: Blue Helix]
#26878885 - 08/13/20 04:33 PM (3 years, 5 months ago) |
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Find a microwave on the side of the road it moves a little slower and is easy to just plug in. I use them for all sorts of things.
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Blue Helix
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Re: How to make a _good_ magnetic stirrer for cheap [Re: greenmachine78]
#26878919 - 08/13/20 04:52 PM (3 years, 5 months ago) |
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Quote:
greenmachine78 said: Find a microwave on the side of the road it moves a little slower and is easy to just plug in. I use them for all sorts of things.
Yeah, I guess you can use a microwave or maybe even a motorcycle idling. Lots of things spin slowly but might not be totally practical. If you'd like this thing to spin slower, that part is super easy. Just get a more geared down motor on Amazon. Instead of 300 PRM at 24V, buy the 100 RPM at 24V and run it on 6V. Or buy the 110V AC version at the exact speed you want and just plug it into the wall. They have motors that go as slowly as you want for about the same price basically.
The speed I recommend is based on my own experiences with a real lab-grade unit that could adjust from 1 RPM to 1000 RPM. I got the used unit for about $40 and it worked for about a decade. Eventually it started to disregulate and spin at random speeds, including stopping for several minutes sometimes. It's kind of worthless now because it'll jerk really fast and the magnet cannot keep up. That ends up making all sorts of noise, and I hate noise.
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coAsTal
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Re: How to make a _good_ magnetic stirrer for cheap [Re: Blue Helix]
#26879190 - 08/13/20 08:15 PM (3 years, 5 months ago) |
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I like it-- I already have everything but the motor, so I'll let you know when it arrives and I get it built up-- thanks so much for the great DIY TEK.
-------------------- I am certain of nothing but the holiness of the Heart's affections and the truth of Imagination-- John Keats Spore Trading List
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Blue Helix
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Re: How to make a _good_ magnetic stirrer for cheap [Re: coAsTal]
#26879338 - 08/13/20 10:39 PM (3 years, 5 months ago) |
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Quote:
coAsTal said: I like it-- I already have everything but the motor, so I'll let you know when it arrives and I get it built up-- thanks so much for the great DIY TEK.
That motor came within 24 hours to me. It's just a beautiful motor too. I wasn't expecting something as nice as it is. I even opened the gear cage just to check it out, and it looks top notch.
One thing I don't talk enough about is running the cord. I ran mine out of between the two lids. It is normal for the two lids to have a 1/16" between them because the motor's shaft is just a tad too long to fit between them. That let's you run the cord out in the gap, and you can tape both the lids with that tiny gap. It's not a big deal. I'm just telling you so you don't think you did something wrong.
Also the motor is tight in the half-pint. Like I said, I had to bend the terminals sideways to get it to close well.
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Bsdgaou

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Re: How to make a _good_ magnetic stirrer for cheap [Re: Blue Helix]
#26879347 - 08/13/20 10:48 PM (3 years, 5 months ago) |
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Magnetic coffee stirer is 12€ brand new. Just saying...
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Blue Helix
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Re: How to make a _good_ magnetic stirrer for cheap [Re: Bsdgaou]
#26879371 - 08/13/20 11:07 PM (3 years, 5 months ago) |
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Quote:
Bsdgaou said: Magnetic coffee stirer is 12€ brand new. Just saying...
Like I keep saying: I can make you a fast LC stirrer for about $5 using a PC fan ($3), two magnets (25 cents), and a power box ($2). I don't want to because in the title I said "_good_", but that would be shitty. Those gears in the motor are expensive. That's because they don't sell 100,000,000 of them a year like coffee stirrers. Just saying...
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coAsTal
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Re: How to make a _good_ magnetic stirrer for cheap [Re: Blue Helix]
#26879717 - 08/14/20 08:00 AM (3 years, 5 months ago) |
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Yeah, I toyed with the idea of the PC fan variants-- but I don't want shitty plastic fans running that fast, and the added weights to the fan blades would be far more than they're designed to safely spin. (If I wanted to try that I could have done it with parts I already have.)
It's the small rock-solid little motor that's the key to making it a great DIY- - because it's perfect for this function. I'll post an update once I build mine, so other people can see how easy it is.
BH, you should consider linking this together with your LC reasoning/method post/journal(!), because once people see how you can safely get away from needing SAB/Flow hoods to nock up spawn bags with these things, it all comes together on how great a fit the methods are for a smooth operation--especially for people like me that have extremely limited space for their hobby.
Once I get this spinner built, I'm going to have to decide what type of mushroom I want to try an LC on first.
-------------------- I am certain of nothing but the holiness of the Heart's affections and the truth of Imagination-- John Keats Spore Trading List
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Blue Helix
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Re: How to make a _good_ magnetic stirrer for cheap [Re: coAsTal]
#26882327 - 08/15/20 08:27 PM (3 years, 5 months ago) |
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Quote:
coAsTal said: Yeah, I toyed with the idea of the PC fan variants-- but I don't want shitty plastic fans running that fast, and the added weights to the fan blades would be far more than they're designed to safely spin. (If I wanted to try that I could have done it with parts I already have.)
It's the small rock-solid little motor that's the key to making it a great DIY- - because it's perfect for this function. I'll post an update once I build mine, so other people can see how easy it is.
BH, you should consider linking this together with your LC reasoning/method post/journal(!), because once people see how you can safely get away from needing SAB/Flow hoods to nock up spawn bags with these things, it all comes together on how great a fit the methods are for a smooth operation--especially for people like me that have extremely limited space for their hobby.
Once I get this spinner built, I'm going to have to decide what type of mushroom I want to try an LC on first.
Yeah. If you have any questions about ANYTHING LC-related, let me know. I actually happened to have the M3 screws for the top of this motor, but it's just so easy to make it hot glued that I didn't use them.
PS - I also linked this to my LC lid-making post as you suggested.
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Hobbit GDF
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Re: How to make a _good_ magnetic stirrer for cheap [Re: Blue Helix]
#26882336 - 08/15/20 08:33 PM (3 years, 5 months ago) |
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Very cool. This is how my homemade one looks. Works so fricking good too. Just sit the media bottles on top the lid. I love this stir plate. Why are real ones expensive?
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Hobbit GDF
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Re: How to make a _good_ magnetic stirrer for cheap [Re: lovepotion]
#26882344 - 08/15/20 08:41 PM (3 years, 5 months ago) |
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Quote:
lovepotion said: He's back! This looks 1000x more legit than the computer fan plates that are stopped with fingers
I like how you incorporate hot glue into your teks. A signature perhaps. Hot Blue Gun
Why are PC fans not good? I can stop it with my finger. But I have a lid and never need to touch it. Its strong and stirs very well
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Blue Helix
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Re: How to make a _good_ magnetic stirrer for cheap [Re: Hobbit GDF]
#26882422 - 08/15/20 09:39 PM (3 years, 5 months ago) |
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Quote:
Hobbit GDF said:
Quote:
lovepotion said: He's back! This looks 1000x more legit than the computer fan plates that are stopped with fingers
I like how you incorporate hot glue into your teks. A signature perhaps. Hot Blue Gun
Why are PC fans not good? I can stop it with my finger. But I have a lid and never need to touch it. Its strong and stirs very well
This is the last time I cover this again: a PC fan does not operate nearly slow enough to be optimal. I played around for many years an expensive lab stirrer that could go from 0 to 1000 with the turn of a knob. I found that anything higher than about 200 RPM just blended the whole LC so there was no character left in it to see contamination. It just became a mess of snot basically. At that RPM, mold looked just like a good LC. So if that doesn't bother you, you can make a PC-fan based one for about $5 or less. Regretfully, I used them for some years myself, and I wasted time using them too because they just were basically a blender with no way to see the mycelium characteristics as it grew. It's kind of like if someone took their agar plate each day and ran it through a meat grinder. I guess if the plate was clean, it wouldn't matter.
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Blue Helix
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Re: How to make a _good_ magnetic stirrer for cheap [Re: Blue Helix] 1
#26890011 - 08/20/20 12:31 PM (3 years, 5 months ago) |
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I just wanted to emphasize my point about why lower RPM LCs matter. Below is an animation of a lower RPM LC. It's the motor in this thread being run at 9 volts, one of the recommended voltages. Notice how the balls are not smashed up and do not form a cloudy slurry as they would with a typical PC-fan-based stirrer. I've seen enough agar plates to practically know what this would look like on agar, and it's not contamination. Contamination would be if this was like heavy snot flying around, but unfortunately, with a PC-fan-based stirrer or with the daily swishing technique, it'd look like that too. The easiest way to tell if a LC is developing right, is to slow down the stirring to under 150RPM or so. In this case, 5V would probably be even better, but this is fine too. My final question is this: isn't that information worth around $10 or $15 extra to you? It is for me. If at the end you want to wreck the structure up, you can just shake it hard (although these balls are not strong enough to jam a syringe typically).
PS - Also, note there is a tiny bit of cloudiness. That's fine as long as it doesn't get more cloudy. This is typical of LCs that might have a very minor degree of bacteria in them early on or for some types of dry malt extract that just happen to have solids until the mycelium pulls it out. In 48 hours that would totally go away here.
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dothedew69
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Re: How to make a _good_ magnetic stirrer for cheap [Re: Blue Helix]
#26891604 - 08/21/20 11:50 AM (3 years, 5 months ago) |
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Looks great, I just ordered all the parts on Amazon. Now I realize you can control the speed by the power supply but do you think you can put a dimmer switch in the mix and control the rpm that way? I may try it out, little more research to see if I can made something. Could swap it out with a higher rpm motor and have the ability to break it up real well if there are no contams and you plan on using most of the lc. Going to be doing lc and agar, I need stuff to keep me occupied for 6 weeks “vacation”
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Blue Helix
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Re: How to make a _good_ magnetic stirrer for cheap [Re: dothedew69]
#26892464 - 08/21/20 08:40 PM (3 years, 5 months ago) |
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Quote:
dothedew69 said: Looks great, I just ordered all the parts on Amazon. Now I realize you can control the speed by the power supply but do you think you can put a dimmer switch in the mix and control the rpm that way? I may try it out, little more research to see if I can made something. Could swap it out with a higher rpm motor and have the ability to break it up real well if there are no contams and you plan on using most of the lc. Going to be doing lc and agar, I need stuff to keep me occupied for 6 weeks “vacation”
You definitely can put a variable voltage supply on it. I'm not sure going super high to blend it matters too much, though. You can always just shake it before you draw it. At 24V that one maxes out at 300 RPM, which is plenty fast in my opinion. But you might want to get one that is faster and use an even lower voltage most of the time (say 3V or something like that). I've not looked at variable supplies, but I'm sure there are a million of them on Amazon and eBay. Stuff like that is super easy to find.
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Blue Helix
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Re: How to make a _good_ magnetic stirrer for cheap [Re: dothedew69]
#26892523 - 08/21/20 09:19 PM (3 years, 5 months ago) |
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Quote:
dothedew69 said: Looks great, I just ordered all the parts on Amazon. Now I realize you can control the speed by the power supply but do you think you can put a dimmer switch in the mix and control the rpm that way? I may try it out, little more research to see if I can made something. Could swap it out with a higher rpm motor and have the ability to break it up real well if there are no contams and you plan on using most of the lc. Going to be doing lc and agar, I need stuff to keep me occupied for 6 weeks “vacation”
Because the power requirements are super tiny, you can also just put a variable resistor inline with the motor and control the voltage that way too. That's what I'd do if I wanted to do it. You might need to run some numbers to know what size for the resistor. I know this motor only takes about 30mA at 9V, so that gives you an idea of the ballpark of what size you need. I'd assume a 0 to 1K-ohm would work fine.
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starbones
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Re: How to make a _good_ magnetic stirrer for cheap [Re: Blue Helix]
#26892555 - 08/21/20 09:46 PM (3 years, 5 months ago) |
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Magnetic stir plates are all of $20 on Amazon with speed control and work absolutely fine. Why bother with this from an objective perspective?
I just checked and the one I have been using has gone up to $29 USD but come on. For the time spent putzing around on stuff like this a person could have stocked shelves or mowed lawns and have themselves something made decently WITH speed control.
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Blue Helix
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Re: How to make a _good_ magnetic stirrer for cheap [Re: starbones] 1
#26892582 - 08/21/20 10:08 PM (3 years, 5 months ago) |
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Quote:
starbones said: Magnetic stir plates are all of $20 on Amazon with speed control and work absolutely fine. Why bother with this from an objective perspective?
I just checked and the one I have been using has gone up to $29 USD but come on. For the time spent putzing around on stuff like this a person could have stocked shelves or mowed lawns and have themselves something made decently WITH speed control.
Wow, this is strange. People keep reasking the same questions over and over and over. Don't they read anything I write? Okay, this is the LAST FUCKING TIME I say this. After this post, I will stop replying.
The same question I've answered like fifteen times: "Why not buy the super cheap ones like this one? if they only cost $29 bucks?"
https://www.amazon.com/Magnetic-stirrer-magnetic-Stirring-Capacity/dp/B072K24X5P/
Answer: Because they are total shit. I actually bought two different ones on eBay direct from China (including the one in the Amazon above), and they were so bad that I threw them in the trash. First, they operated WAY too fast, and that alone is a reason why your LCs won't work that well. And why do they operate fast? Open them up LIKE I DID and you'll see why: they use a PC fan motor or something very similar. Two problems: (a) those motors are not designed for ANY load and you are loading them down with this, and (b) they cannot turn at 150 RPM or thereabouts because they are direct drive (no gears). You might get them down to 400 RPM on a good day, but since the motor wasn't designed to operate that speed, it'll last you all of a few months.
It's funny how people assume, for some odd reason, that I would not have thought about this carefully before I posted. Have you even seen the stuff I post? I guess not. Believe me, I can do anything you can a lot cheaper. I'm obsessed with price, not because money is a problem for me but because it's a game. So sure you can buy the shit ones on Amazon that might last you a year and turn your LC too fast, or you can sit down all of 10 minutes and make one yourself. That's the point of this thread: to describe how to make one that isn't shit and blend your LC into oblivion.
Now is it possible that someone is selling one that isn't shit that is cheap (as it should be)? COURSE IT IS, and if you know who makes one that operates around 150 RPM and costs $20, please let me know. I couldn't find one like that, but I haven't tried every cheap piece of shit coming out of China. If you do find one, I will delete this entire thread IMMEDIATELY, but you still haven't so I won't delete it.
Edited by Blue Helix (08/21/20 10:13 PM)
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Blue Helix
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Re: How to make a _good_ magnetic stirrer for cheap [Re: Blue Helix]
#26892759 - 08/22/20 01:33 AM (3 years, 5 months ago) |
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It has come to my attention that at this point, this thread is useless. Essentially people are just trolling me, and getting a kick out of my reaction. Toward that end and because I'm such a nice guy, let me provide one last absurd post for the enjoyment of the trolls, okay?
While I'm glad I can provide some meager level of entertainment to you, I actually find it kind of annoying and, ultimately, boring personally. If someone would like to message me with an alternative commercial magnetic stirrer that is inexpensive (say less than $20) and doesn't spin over say 200 RPM, I would be greatly appreciative, but I somehow doubt that will happen (in the same way I doubt anyone reading this has achieved 320% biological efficiency as I have). I'm out of here.
*mic drop*
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dirtybirdx
getting better

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Re: How to make a _good_ magnetic stirrer for cheap [Re: Blue Helix]
#26892842 - 08/22/20 03:06 AM (3 years, 5 months ago) |
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Thanks Blue, I love this so much.
I really geek out on my lab and lab equipment, even though it’s not much.
I’m totally doing this. I’ll probably find a different base for it but I love the simplicity.
Only thing is, I’m not into LC yet.
I think your tek will push me over the edge, plus I want those faster jar colonization times 😋
Hmm now to crash course LC/LI.
-------------------- Need help?

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lovepotion
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Re: How to make a _good_ magnetic stirrer for cheap [Re: Blue Helix]
#26892849 - 08/22/20 03:15 AM (3 years, 5 months ago) |
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I really appreciate this thread, and I apologize if my first reply felt trollish. I was actually being entirely sincere when I said I love how you utilize hot glue, however I can see now how that could have been interpreted as pretentious or sarcastic. I know better than most that you are a master of the craft, far exceeding what many others will ever accomplish.
The entire point in him posting this was to share a new discovery, and some knowledge that only years and years of careful experimenting and observing earns. So thank you Blue Helix for dropping in and passing this on. Because of this thread, I discovered your LC lid tek, and I used those links you shared to purchase the syringe filters and vacutainers for cheaper than I’ve ever seen. So now I have supplies for LC lids that I can share and use for years to come.
So even if the ones on Amazon cost less and performed just as well, I’d still like knowing how to build my own. Why? First, because this hobby is exactly that, a hobby. Hobbyists like me, who are driven by curiosity, usually dedicate time and love to their craft. Wouldn’t you rather know how to build and control the very devices in which fuel the insatiable fire of mycological pursuit?
Secondly, the reason why this thread is valuable is because amazon isn’t an ethical place to give my energy and money to. Amazon isn’t here to help the world be a better place. I feel sorry for those who are making a habit out of amazon services, instead of sourcing supplies from much better companies.
I was actually going to post pictures of the lids I made last night- here they are being constructed with the non Amazon sourced parts you shared, and let me say this- I really enjoyed the process of construction these myself. I take some fucking pride in my craft! With that being said, I still use my Amazon stir plate, mostly because the only other alternative I knew about was computer fan stir plates, which are not any better. So when this little thing dies, I’ll be sure to reference this thread for guidance on how to build a better, cheaper one.
Blue Helix is the king of liquid culture. Look back in time and see what he was doing long before anyone else. A true inventor who earned that trusted cultivator tag. I have learned an incredible amount from your posts and am delighted to spot you still investing in the hobby. Let the trolls be, they don’t know any better
-------------------- Staying Out to Lunch
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Blue Helix
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Re: How to make a _good_ magnetic stirrer for cheap [Re: lovepotion] 1
#26894507 - 08/22/20 11:00 PM (3 years, 5 months ago) |
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So like I said before I would update this thread if there was anything useful to say, but I have not nor have any interest in replying to it. If you have a real question, just private message me. That tends to get rid of the trolls since trolls thrive on attention more than anything.
I wanted to update this by saying that I did an animated GIF analysis of the spinning disc above running the motor I recommend at 9V. I had said it looked around 150 RPM to me. The analysis showed the motor recommended in this thread does in fact turn just about exactly 150 RPM (maybe 160) at 9V.
The reason I am so good detecting this kind of rotation visually is because like I said I spent a lot of time studying this aspect of magnetic stirrers. I had a lab one that allowed one to adjust from about 50 RPM to 1500 RPM. I played with lots of speeds, so I know my speeds pretty well. For example, I know the fast speeds of a crap magnetic stir plate (the $20 or $30 junk on Amazon or eBay) or PC fan and the slower desirable speeds for this purpose, which are generally under 200 RPM.
Someone asked about blending the LC after it's developed: that happens around 700 RPM or greater OR when you draw the LC into a syringe (due to the shearing effects of being drawn into a needle). So I don't see the point of blending it. Just like I don't see the point blending your finished agar plates into a jelly either. An LC is just a 3D agar plate to me.
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Blue Helix
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Re: How to make a _good_ magnetic stirrer for cheap [Re: Blue Helix]
#26895449 - 08/23/20 01:49 PM (3 years, 5 months ago) |
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Quote:
How to easily add a speed control without buying an expensive variable-voltage power supply
Someone asked me about adding a speed control. I measured the motor above at around 300 ohms with no load powered at 9V. So if you want a speed control, buy a DC supply is 24V (do not buy one over this). Then add a potentiometer (aka a "pot" or variable resistor) of 0-1000 ohms in series with the motor. You can probably find one of those on eBay for less than $1 delivered to you. That should allow around 50 to 300 RPM control with the center being 150RPM (9V).
If you'd like to go faster than 300 RPM so you can blend your LC for some reason like in a blender--again this really serves no practical purpose since drawing the LC out blends it--you need to buy a motor that is rated higher (either the 600 RPM or 1000 RPM at 24V version). The same principle applies though: buy the 24V supply and add a potentiometer of say 0 to 1500-ohm in series with it. Just keep in mind that motors that are rated faster have a limit to how slowly you can run them. A non-silent (the so-called silent ones just have a resistor built into them) PC fan is rated, for example, at around 2500 RPM at full voltage, so you might be able to get it down to 600 RPM or so. But if you try to go down to say 150 RPM by using a lower voltage or bigger resistor--and I've tried that before--the fan motor may just stop randomly. Also running a motor far, far slower than it is rated like that is harder on the motor, which is exactly why the the eBay "junk" magnetic stirrer stopped working for me since the motor eventually just blew out after I tried to use a lower voltage power supply than it was rated to slow it down further.
Edited by Blue Helix (08/23/20 01:59 PM)
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Blue Helix
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Re: How to make a _good_ magnetic stirrer for cheap [Re: lovepotion]
#26895516 - 08/23/20 02:20 PM (3 years, 5 months ago) |
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Quote:
lovepotion said: I really appreciate this thread, and I apologize if my first reply felt trollish. I was actually being entirely sincere when I said I love how you utilize hot glue, however I can see now how that could have been interpreted as pretentious or sarcastic. I know better than most that you are a master of the craft, far exceeding what many others will ever accomplish.
The entire point in him posting this was to share a new discovery, and some knowledge that only years and years of careful experimenting and observing earns. So thank you Blue Helix for dropping in and passing this on. Because of this thread, I discovered your LC lid tek, and I used those links you shared to purchase the syringe filters and vacutainers for cheaper than I’ve ever seen. So now I have supplies for LC lids that I can share and use for years to come.
So even if the ones on Amazon cost less and performed just as well, I’d still like knowing how to build my own. Why? First, because this hobby is exactly that, a hobby. Hobbyists like me, who are driven by curiosity, usually dedicate time and love to their craft. Wouldn’t you rather know how to build and control the very devices in which fuel the insatiable fire of mycological pursuit?
Secondly, the reason why this thread is valuable is because amazon isn’t an ethical place to give my energy and money to. Amazon isn’t here to help the world be a better place. I feel sorry for those who are making a habit out of amazon services, instead of sourcing supplies from much better companies.
I was actually going to post pictures of the lids I made last night- here they are being constructed with the non Amazon sourced parts you shared, and let me say this- I really enjoyed the process of construction these myself. I take some fucking pride in my craft! With that being said, I still use my Amazon stir plate, mostly because the only other alternative I knew about was computer fan stir plates, which are not any better. So when this little thing dies, I’ll be sure to reference this thread for guidance on how to build a better, cheaper one.
Blue Helix is the king of liquid culture. Look back in time and see what he was doing long before anyone else. A true inventor who earned that trusted cultivator tag. I have learned an incredible amount from your posts and am delighted to spot you still investing in the hobby. Let the trolls be, they don’t know any better
Hey, thank you for your post. I was referring to the person that mentioned buying an Amazon one as a troll. I opened this discussion with saying I had tried the ones on eBay, and the two cheap ones I bought were too fast. I then lowered the voltage supply on them, and they stopped working at any speed. That's why I built one, not because I like doing crafty things (because I really don't to be honest).
Having said that I am CERTAIN that there either is a slow one out there or there will be for cheap soon. And if someone finds one and can confirm it, PLEASE let me know! I want to mention it here then! The reason I know they either do exist or will is simply because I've been around long enough to remember some things. For example, did you know that back in 2000 I couldn't find a scale that did over 150g at 0.1g accuracy for under $130?!?! That almost seems impossible now! There is a whole line of scales that out there now that have calibration controls and can measure up to 500g at 0.01g accuracy (not just resolution but ACCURATELY too) for about $12?! Why everyone doesn't own one is a mystery to me.
The same applies to high-accuracy pH probes. Just five years ago, you couldn't get one that measured +/-0.02 pH accurately for under $110! Now the you can get a decent one on Amazon or eBay that is 0.02 accurate again with calibration controls for $12! Again, why doesn't everyone own one for the casings? Who knows. My point is that things change, and I am pretty much sure that a low-RPM magnetic spinner is either out there or will soon be for under $20. Until someone helps me find it, though, this thread was to help folks make one today.
PS - Of course, I didn't take offense to hot glue! LOL I'll accept I'm the king of hot glue. It's stupid, but hey, the stuff works in a pinch when strength isn't your goal and you know yourself well enough to know you might just screw up the glue application. I love that I can scrape it off and try again too. It's a unique glue.
Edited by Blue Helix (08/23/20 02:27 PM)
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starbones
I'm an alien, I eat uranium.



Registered: 03/04/20
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Re: How to make a _good_ magnetic stirrer for cheap [Re: Blue Helix] 1
#26895548 - 08/23/20 02:40 PM (3 years, 5 months ago) |
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What a fuckin spaz of a reply that was.

$20 shipped with Prime. Goes as dead slow as I want it to and fast enough to blend. I run over 60 monotubs at a given time and need oodles of LC. You can cry that because it is cheap and from China it is going to be bad but for the price of these I will sit them absolutely next to any bodged together unit. I can keep a quart of LC on there barely turning just fine.
I look forward to your next wall of text telling me how impossibly wrong I must be for not hacking together a rickety contraption instead of spending the equivelant of 1.5 hours of minimum wage employment on a unit with an actual speed controller.
-------------------- Listen, I'm steel fisted with the iron lung Heavy metal ballads out the guitar where lions run.
 
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coAsTal
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Re: How to make a _good_ magnetic stirrer for cheap [Re: starbones]
#26895550 - 08/23/20 02:43 PM (3 years, 5 months ago) |
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Shut the fuck up dude-- you're the one missing the point.
This thread wasn't for you to come in pissing all over it telling the OP that his DIY design wasn't worth the time and effort.
It is to those that want to do it. If you have a great solution for yourself, that's swell.
Get the fuck out of here--
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starbones
I'm an alien, I eat uranium.



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Re: How to make a _good_ magnetic stirrer for cheap [Re: coAsTal]
#26895591 - 08/23/20 03:13 PM (3 years, 5 months ago) |
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I asked a question about the benefit specifying an objective perspective and got a train of thought response about how this is so much better and that mine is somehow shit with absolutely no evidence of that. Then chooses to label someone with a differing opinion as a fucking troll as it it somehow solidifies his position and negates someone elses? Ad hominems aren't groovy.
He's perfectly capable of acting like an arsehole on his own without the peanut gallery chiming in. The question asked was what benefit does this offer over something prebuilt for very little money and there is still no answer to that beyond some damned opinion. Good Christ.
-------------------- Listen, I'm steel fisted with the iron lung Heavy metal ballads out the guitar where lions run.
 
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Pastywhyte
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Re: How to make a _good_ magnetic stirrer for cheap [Re: starbones] 1
#26895617 - 08/23/20 03:36 PM (3 years, 5 months ago) |
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Quote:
starbones said: I asked a question about the benefit specifying an objective perspective and got a train of thought response about how this is so much better and that mine is somehow shit with absolutely no evidence of that. Then chooses to label someone with a differing opinion as a fucking troll as it it somehow solidifies his position and negates someone elses? Ad hominems aren't groovy.
He's perfectly capable of acting like an arsehole on his own without the peanut gallery chiming in. The question asked was what benefit does this offer over something prebuilt for very little money and there is still no answer to that beyond some damned opinion. Good Christ.
Given the OP’s tenure and contributions in the community I’m feeling like you’re the one acting out here. His “damned opinion” is worth a fair bit to me, if it’s not good enough for you then you don’t need to take it. You’ve made your point and he has made his. Let’s keep it civil going forward. That means not calling people arseholes. Thanks.
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Blue Helix
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Re: How to make a _good_ magnetic stirrer for cheap [Re: starbones]
#26895630 - 08/23/20 03:41 PM (3 years, 5 months ago) |
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Quote:
starbones said: What a fuckin spaz of a reply that was.

$20 shipped with Prime. Goes as dead slow as I want it to and fast enough to blend. I run over 60 monotubs at a given time and need oodles of LC. You can cry that because it is cheap and from China it is going to be bad but for the price of these I will sit them absolutely next to any bodged together unit. I can keep a quart of LC on there barely turning just fine.
I look forward to your next wall of text telling me how impossibly wrong I must be for not hacking together a rickety contraption instead of spending the equivelant of 1.5 hours of minimum wage employment on a unit with an actual speed controller.
Okay, trolly troll, I'm feeling good today so I'll give you the attention you need to feel important. Get your dick out because I bet this post is going to turn you on (even though it's my last to you). So here comes my "wall of text" just for you.
First, why would I care how many monotubs you've done? You think monotubs are something advanced? Isn't that like the step above PF Tek or something (it's been like 20 years for me)? I don't get your point, but I'm glad your monotub operation is going smoothly. Back to the facts.
So, uh, why didn't you include an Amazon link to the unit? Do you know about ctrl+c and ctrl+v? Maybe you should look it up and give it a try. Here's the unit on Amazon today for 50% more than you claim at $30 (not during some black Friday sale):
https://www.amazon.com/ANZESER-Magnetic-Stirrer-Stirring-Capacity/dp/B07J59QVGQ/
So not only did you fail to provide a link of your $20 unit so I could verify the price and probably buy one myself, but you also failed to provide an animated GIF or YouTube video so you can prove it going say 200 RPM or less. I provided two such animations, and you cannot provide me one?! Too much work for ya? Maybe study my "walls of text" to improve your posting style. Stuff like coherent thought and evidence kind of matters.
So you didn't think the one I bought also said 0-3000 RPM and had a picture of it going around 1000 RPM too? It did--for the same price of $30--and it didn't work below about 200 RPM without stopping randomly. It did here..
Now I hope my reply made you feel wonderful inside. Oh and be sure to wipe off the spots on your trousers before mom comes down.
So let's summarize since this wall of text is too short: A guy (me) posts how to do something he couldn't do without plopping down a bit too much money, and you attack it. Why not just provide a link and an animation of yours going at a lower RPM? This is why I called you a troll. Your response here was defensive and clearly an attempt to provoke rather than inform. In turn I mirror you in my reply and you do it again, etc. for all eternity. It's boring. There were a hundred nice ways to say what you wanted to say and prove it, but you're a troll so didn't use them.
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starbones
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Re: How to make a _good_ magnetic stirrer for cheap [Re: Blue Helix]
#26895639 - 08/23/20 03:52 PM (3 years, 5 months ago) |
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Holy. Fuck.
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starbones
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Re: How to make a _good_ magnetic stirrer for cheap [Re: starbones]
#26895661 - 08/23/20 04:15 PM (3 years, 5 months ago) |
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Your "slow is better therefore mine is better" argument falls over flat when you post a gif of your LC going mach chicken compared to a gentle stir like this.
You claimed these units were too fast due to their speed controllers being shit but here we are. I fully expect another wall of text with you ranting some kind of nonsense again that your hackjob is better because X when that X is proven to be bullshit.
I asked you why your stirrer was a better idea, you provided an argument and bleated for a gif. I can turn this down even slower but at that speed my LC's grow considerably slower and there is a chance of stalling the bar. I am trying my absolute damndest to be civil here but you are coming off as increasingly condescending and surely should knock off that stupid troll line. I asked you what made this design of yours OBJECTIVELY better and you took it as an insult or attack given your reply.
You said these units were incapable of going slow enough. There you are, with the speed controller you claim cannot do it.
Edit: You told people these things are doing 1000 rpm in your first post for crying out loud. That is 1/3 what this unit is capable of and much, much faster than reality as you can see with your own eyes. Many, many homebrewers use this exact model or the other dozen of the same carbon copy ones for slowly, gently stirring yeast starters, cultures and such.
-------------------- Listen, I'm steel fisted with the iron lung Heavy metal ballads out the guitar where lions run.
 
Edited by starbones (08/23/20 04:30 PM)
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lovepotion
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Re: How to make a _good_ magnetic stirrer for cheap [Re: starbones] 2
#26895894 - 08/23/20 07:31 PM (3 years, 5 months ago) |
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Blue's design serves a greater purpose specifically for creating healthy, easily identifiable, clean liquid culture. There are no other cheap stir plates on the market that do that.
I have the same stir plate as you and my liquid culture looks exactly like yours. It does not spin slow enough without stalling to create the 3-D agar pucks like shown in the original post. The "objective facts" you are looking for are right there in the first post. No one else has LC that looks like that, which as he described, with objective proof, with pictorial representation, how useful his design is and for good reason.
You are using the same stir plate as everyone else here, we all know exactly what speed it spins, what setting causes the stir bar to stall, and how fast its max speed is before the stirbar looses velocity and gets thrown off center.
Here are my thoughts- The language you've chosen to use," Puntzing around, Hack job, Mock chicken," are not selling me on your expertise. I don't like reading negative posts, or boarder line aggressive responses. A lot of people are going thru stuff right now, and this kind of insensitive language only adds more tension to the thread. You have not shared any good factual information that everyone doesnt already know first hand. Again, the stir plate you use is the same as everyone elses.
Think about this- The equipment we all use isnt designed specifically for mycology. Some of the experts in the field have trialed many many designs, and spent their energy, time and money perfecting the process. The monotubs you are using, the substrate you use, the filters you use on your monotubs, the liners you use in your monotubs, the stir plate you use, the LC recipe you follow, have all been discovered and shared by people who werent you. You are simply copying the techniques of those who came before you. SO why would you knock on something being shared that someone else designed, which serves a specific purpose directly related to the advancement of home mycology when all you are doing is copying the ideas of those who came before you?
-------------------- Staying Out to Lunch
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starbones
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Re: How to make a _good_ magnetic stirrer for cheap [Re: lovepotion]
#26895966 - 08/23/20 08:29 PM (3 years, 5 months ago) |
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Quote:
lovepotion said:
No one else has LC that looks like that.


They go slow enough to make the naval mines.
I'm out.
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lovepotion
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Re: How to make a _good_ magnetic stirrer for cheap [Re: starbones]
#26896153 - 08/23/20 11:07 PM (3 years, 5 months ago) |
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good luck out there pal
-------------------- Staying Out to Lunch
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dothedew69
Relearning



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Re: How to make a _good_ magnetic stirrer for cheap [Re: Blue Helix] 1
#26909682 - 08/31/20 12:42 PM (3 years, 4 months ago) |
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I made one of these too but I ran into some issues and I figured it was probably due to the lid size. When I used the jar and put a hole in the lid I couldn’t tighten the lid down. So I used a forstner 1/2 bit and cut a hole in it which fit the entire motor through and after wiring it, it stuck up like 1/16 of an inch which allowed me to glue it to the lid to be stationary. I put some caulk on the bottom so it would be extra secured and cushioned as well. Buuuut, ran into another problem, now with the added height the metal lid with weights was hitting the top of the second lid. Found some styrofoam laying around and cut some pieces to act as spacers. Glued the top spinning lid down with my magnets and then glued the top lid to the styrofoam. I will have to take it apart however, the magnets I used were way too big and way too powerful so I ordered some 15mmx3mm magnets to replace it, going to use 3 of them. But considering how it is now it works perfect. When I make my few changes I’m going to shave the foam down and wrap the thing in colored craft foam for a nice finished look. Here’s how it looks right now, it works beautifully thank you!
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Blue Helix
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Re: How to make a _good_ magnetic stirrer for cheap [Re: starbones]
#26930106 - 09/11/20 02:34 PM (3 years, 4 months ago) |
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Quote:
starbones said:

Hey, before the total drivel above that I basically skimmed over, the troll dude does show an interesting picture of slow spinning culture. That actually was interesting. Can anyone else with the maturity of an adult confirm this speed from a unit under $30?
So all I need is (a) the exact model your purchased, (b) an animation demonstrating the magnet's turning speed at the lowest stable setting (not the LC's turning speed but the magnet's), (c) the total price including shipping, and (c) the source of your purchase.
I'd love nothing more than to close this discussion with a commercial alternative for a reasonable price. I couldn't find it, but since troll man likes to show pictures but leave somewhat critical details unsaid, I need you all to help me.
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Blue Helix
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Re: How to make a _good_ magnetic stirrer for cheap [Re: dothedew69]
#26930282 - 09/11/20 03:58 PM (3 years, 4 months ago) |
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Quote:
dothedew69 said: I made one of these too but I ran into some issues and I figured it was probably due to the lid size. When I used the jar and put a hole in the lid I couldn’t tighten the lid down. So I used a forstner 1/2 bit and cut a hole in it which fit the entire motor through and after wiring it, it stuck up like 1/16 of an inch which allowed me to glue it to the lid to be stationary. I put some caulk on the bottom so it would be extra secured and cushioned as well. Buuuut, ran into another problem, now with the added height the metal lid with weights was hitting the top of the second lid. Found some styrofoam laying around and cut some pieces to act as spacers. Glued the top spinning lid down with my magnets and then glued the top lid to the styrofoam. I will have to take it apart however, the magnets I used were way too big and way too powerful so I ordered some 15mmx3mm magnets to replace it, going to use 3 of them. But considering how it is now it works perfect. When I make my few changes I’m going to shave the foam down and wrap the thing in colored craft foam for a nice finished look. Here’s how it looks right now, it works beautifully thank you!

Yeah, it's REALLY tight in that half-pint jar and the second lid for that matter. I almost just wrote that folks should use a full pint jar with a spacer of some sort for the lid. How ever you got it to work, though, congrats!
Edited by Blue Helix (09/11/20 04:06 PM)
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bodhisatta 
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Re: How to make a _good_ magnetic stirrer for cheap [Re: Blue Helix]
#26930297 - 09/11/20 04:08 PM (3 years, 4 months ago) |
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Quote:
Blue Helix said: It has come to my attention that at this point, this thread is useless. Essentially people are just trolling me, and getting a kick out of my reaction. Toward that end and because I'm such a nice guy, let me provide one last absurd post for the enjoyment of the trolls, okay?
While I'm glad I can provide some meager level of entertainment to you, I actually find it kind of annoying and, ultimately, boring personally. If someone would like to message me with an alternative commercial magnetic stirrer that is inexpensive (say less than $20) and doesn't spin over say 200 RPM, I would be greatly appreciative, but I somehow doubt that will happen (in the same way I doubt anyone reading this has achieved 320% biological efficiency as I have). I'm out of here.
*mic drop*
Jesus dude grow up. One random person made you cry this much... And you're still going on about it. Ignore the fucking guy lol. All he did was post a very reasonable reply. Why would you build this if you can get something as good or better for under 50
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Re: How to make a _good_ magnetic stirrer for cheap [Re: Blue Helix]
#26930303 - 09/11/20 04:11 PM (3 years, 4 months ago) |
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-------------------- 🅃 🄴 🄰 🄼 🄲 🄻 🄸 🄽 🄶 🅆 🅁 🄰 🄿
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CubePusher
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Re: How to make a _good_ magnetic stirrer for cheap [Re: Blue Helix]
#26930307 - 09/11/20 04:14 PM (3 years, 4 months ago) |
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Any thoughts on a design that could stir like 16 jars at once on the cheap? Just a thought. Probably best to go with a bunch of cheap fans running through some sort of speed controller at that point, right?
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verum subsequentis
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Re: How to make a _good_ magnetic stirrer for cheap [Re: CubePusher]
#26930312 - 09/11/20 04:17 PM (3 years, 4 months ago) |
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This post is strange to me. Your name is "cube pusher", you have 12 posts and you want a stir plate that stirs 16 at a time. hmmmmm
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bodhisatta 
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Re: How to make a _good_ magnetic stirrer for cheap [Re: CubePusher]
#26930315 - 09/11/20 04:19 PM (3 years, 4 months ago) |
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Not cheap but automotive paint used to mostly be stored in these mixing banks/cabinets
https://byrdsautomotive.com
They're constantly stirred by one motor attached to a drivetrain that goes to a stiring bar for each jar
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CubePusher
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Re: How to make a _good_ magnetic stirrer for cheap [Re: bodhisatta]
#26930332 - 09/11/20 04:27 PM (3 years, 4 months ago) |
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Quote:
verum subsequentis said: This post is strange to me. Your name is "cube pusher", you have 12 posts and you want a stir plate that stirs 16 at a time. hmmmmm
It's a play on squarepusher (musician), that math almost checked out though lol
Quote:
bodhisatta said: Not cheap but automotive paint used to mostly be stored in these mixing banks/cabinets
https://byrdsautomotive.com
They're constantly stirred by one motor attached to a drivetrain that goes to a stiring bar for each jar
Creative idea but waaaay too pricey and I'm hoping for something with a relatively small form factor, like a tray I could fit on a shelf.
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bodhisatta 
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Re: How to make a _good_ magnetic stirrer for cheap [Re: CubePusher] 1
#26930338 - 09/11/20 04:31 PM (3 years, 4 months ago) |
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I think if you had a shop that made tinkering cheap for you that you could take one motor and have it drive 16 spinning chucks that each hold a magnet
like an arthur ganson style machine of sorts.
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Blue Helix
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Re: How to make a _good_ magnetic stirrer for cheap [Re: dothedew69]
#26930342 - 09/11/20 04:33 PM (3 years, 4 months ago) |
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Quote:
dothedew69 said: I made one of these too but I ran into some issues and I figured it was probably due to the lid size. When I used the jar and put a hole in the lid I couldn’t tighten the lid down. So I used a forstner 1/2 bit and cut a hole in it which fit the entire motor through and after wiring it, it stuck up like 1/16 of an inch which allowed me to glue it to the lid to be stationary. I put some caulk on the bottom so it would be extra secured and cushioned as well. Buuuut, ran into another problem, now with the added height the metal lid with weights was hitting the top of the second lid. Found some styrofoam laying around and cut some pieces to act as spacers. Glued the top spinning lid down with my magnets and then glued the top lid to the styrofoam. I will have to take it apart however, the magnets I used were way too big and way too powerful so I ordered some 15mmx3mm magnets to replace it, going to use 3 of them. But considering how it is now it works perfect. When I make my few changes I’m going to shave the foam down and wrap the thing in colored craft foam for a nice finished look. Here’s how it looks right now, it works beautifully thank you!
A couple quick questions: which motor (RPM @ what voltage) and what voltage did you use to it? And is it almost silent? A big problem I've had in the past with gear head motors is sound. Some of them can be outright loud if running at the full RPM, so that's why I was asking.
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Blue Helix
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Re: How to make a _good_ magnetic stirrer for cheap [Re: JHOVA]
#26930348 - 09/11/20 04:39 PM (3 years, 4 months ago) |
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Quote:
JHOVA said: https://www.amazon.com/ANZESER-Magnetic-Stirrer-Stirring-Capacity/dp/B07J59QVGQ/ref=mp_s_a_1_3?dchild=1&keywords=anzeser+magnetic+stirrer&qid=1599862065&sprefix=anzes&sr=8-3
Its $30 shipped.
Wow, I had no idea this request would be so incredibly difficult for folks. Let me review what I asked:
(a) the exact model your purchased (b) an animation demonstrating the magnet's turning speed at the lowest stable setting (not the LC's turning speed but the magnet's) (c) the total price including shipping, and (c) the source of your purchase.
Now arguably you provided (a) and (c) but the money shot is (b). Like I said, I've ordered two such spinners and they are now in a landfill somewhere.
Again, has anyone bought this exact spinner and have photographic non-altered animation evidence of it running around 100 to 200 RPM? I don't want GIF manipulated animations and stuff. Yes, I can do that myself through a simple animated GIF editor. I want someone who would be kind enough to confirm this.
PS - I don't want 16 spinners. Believe it or not, I had an four spinner one already. I HATED IT! Let me rephrase that: it was loud as fuck and I instantly smashed it with a hammer for the magnets (and the motor was so shitty that I just tossed it). Got the picture? Quiet matters to me more than 4, 8, 16 32, 64, or 128 spinners. I usually have one or two LC going here; I'm not a mushroom lab. And I have to sleep in the room they are spinning, and I am a very light sleeper. The leaves rustling outside can wake me up.
Edited by Blue Helix (09/11/20 04:45 PM)
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bodhisatta 
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Re: How to make a _good_ magnetic stirrer for cheap [Re: Blue Helix]
#26930356 - 09/11/20 04:45 PM (3 years, 4 months ago) |
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Doctored gifs
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Blue Helix
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Re: How to make a _good_ magnetic stirrer for cheap [Re: bodhisatta]
#26930358 - 09/11/20 04:47 PM (3 years, 4 months ago) |
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Quote:
bodhisatta said: Doctored gifs 
Oh, it's a thing! I'll show you the one I like:
https://ezgif.com/
Those guys are awesome. You can make a porno with the load lasting a full five minutes with them! j/k I'm not interested in seeing that.
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JHOVA
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Re: How to make a _good_ magnetic stirrer for cheap [Re: Blue Helix]
#26930364 - 09/11/20 04:51 PM (3 years, 4 months ago) |
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You really are something else and i thought my wife was demanding and emotional. I use LI and syringes npt LC, and i looked up the stir plate as a favor to the readers. You can take it from here chief.
-------------------- 🅃 🄴 🄰 🄼 🄲 🄻 🄸 🄽 🄶 🅆 🅁 🄰 🄿
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Blue Helix
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Re: How to make a _good_ magnetic stirrer for cheap [Re: JHOVA]
#26930388 - 09/11/20 05:03 PM (3 years, 4 months ago) |
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Quote:
JHOVA said: You really are something else and i thought my wife was demanding and emotional. I use LI and syringes npt LC, and i looked up the stir plate as a favor to the readers. You can take it from here chief.
Okay and thank you for calling me chief - makes me feel more important than Trusted Cultivator. Maybe I could become the Trusted Cultivator Chief or TCC? Hey gotta dream big you know!
Well, if anyone could show it off in an animation, that would be great. Given I think LCs are the best thing since sliced bread, I'm really curious about it. $30 is right at the border between "Kind of pricey for a spinning magnet" and "We know you need this so we will now totally rip you off with the old 'lab equipment' serious sounding shtick". I'd rather see it at $20 but even at $30 it sounds pretty good if it works just perfectly.
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CubePusher
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Re: How to make a _good_ magnetic stirrer for cheap [Re: bodhisatta]
#26930516 - 09/11/20 06:17 PM (3 years, 4 months ago) |
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Quote:
Blue Helix said: PS - I don't want 16 spinners. Believe it or not, I had an four spinner one already. I HATED IT! Let me rephrase that: it was loud as fuck and I instantly smashed it with a hammer for the magnets (and the motor was so shitty that I just tossed it). Got the picture? Quiet matters to me more than 4, 8, 16 32, 64, or 128 spinners. I usually have one or two LC going here; I'm not a mushroom lab. And I have to sleep in the room they are spinning, and I am a very light sleeper. The leaves rustling outside can wake me up.
Understandable, I was just looking for ideas. Noise isn't as much of an issue for me as that stuffs nowhere near my bedroom. I'd like that kind of capacity for the gourmets though. Thanks for your write ups lately by the way, that LC looks bomb.
Quote:
bodhisatta said: I think if you had a shop that made tinkering cheap for you that you could take one motor and have it drive 16 spinning chucks that each hold a magnet
like an arthur ganson style machine of sorts.
Good idea, there's a shop down the road I'm friendly with. Might have to spend a few evenings there.
Edited by CubePusher (09/11/20 06:39 PM)
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Blue Helix
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Re: How to make a _good_ magnetic stirrer for cheap [Re: CubePusher]
#26930593 - 09/11/20 07:00 PM (3 years, 4 months ago) |
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Quote:
CubePusher said:
Quote:
Blue Helix said: PS - I don't want 16 spinners. Believe it or not, I had an four spinner one already. I HATED IT! Let me rephrase that: it was loud as fuck and I instantly smashed it with a hammer for the magnets (and the motor was so shitty that I just tossed it). Got the picture? Quiet matters to me more than 4, 8, 16 32, 64, or 128 spinners. I usually have one or two LC going here; I'm not a mushroom lab. And I have to sleep in the room they are spinning, and I am a very light sleeper. The leaves rustling outside can wake me up.
Understandable, I was just looking for ideas. Noise isn't as much of an issue for me as that stuffs nowhere near my bedroom. I'd like that kind of capacity for the gourmets though. Thanks for your write ups lately by the way, that LC looks bomb.
Quote:
bodhisatta said: I think if you had a shop that made tinkering cheap for you that you could take one motor and have it drive 16 spinning chucks that each hold a magnet
like an arthur ganson style machine of sorts.
Good idea, there's a shop down the road I'm friendly with. Might have to spend a few evenings there.
The 4-spinner one I had also wasn't working very well because the drive belt was skipping. No doubt that was making it a lot louder. It was actually kind of cool inside, though. There was a motor with a rubber belt (like a timing belt in a car but smaller, of course, and without teeth) that delivered torque to all four magnets with a pully of sorts. The issue was that I think the belt had stretched over the probably decade and a half it was in service, and there wasn't a tension adjustment. And the motor itself was loud and sounded like it was on its way out. I am sure it was wildly expensive when new, though. I'm thinking easily over $400.
I actually wouldn't mind a four-spinner unit using the motor in this write up. Maybe I'll throw something together, but my main point with the write up was to kind of demystify these spinners and put a plug in for cheap gear head motors that can direct drive the magnet at the lower RPMs. I know you can spend $300 down to (so I am told) $30 on one or find them at used lab equipment places or through brewing supplies, but fundamentally they are very simple devices. And it is worth it to get one rather than use a marble if you are half serious about LC techniques. They really do make a difference.
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sonoramo
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Re: How to make a _good_ magnetic stirrer for cheap [Re: Blue Helix]
#26972960 - 10/06/20 09:46 PM (3 years, 3 months ago) |
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Nice write-up. I see that you bought a large number of large Teflon-coated stir bars. On Amazon, they seem kind of expensive for just a piece of steel covered in plastic! Is there a cheaper source?
My home-made ones are a 2cm-long piece of 1/4 inch mild steel rod (6.2mm dia), with two of those same small NdFe craft magnets self-stuck on each end. These cost about $6 for 100 pieces, good for dozens of stir bars plus random crafts and so on. I'm careful to get the two magnets pointing in the same direction. That means they are oriented N-S--N-S, with the steel bar between. They will stick to the steel even if they point N-S--S-N, but then their net dipole moment is small and they don't lock to the stirrer very well.
One problem with this is that the NdFe actually corrodes a bit in solution. It looks ugly but I don't think it actually hurts the culture.
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pitriot
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Re: How to make a _good_ magnetic stirrer for cheap [Re: Bsdgaou]
#26997066 - 10/21/20 09:39 PM (3 years, 3 months ago) |
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Can you link to where you can get a magnetic coffee mixer for that price?
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trippleblack
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Re: How to make a _good_ magnetic stirrer for cheap [Re: starbones]
#27001562 - 10/24/20 04:51 PM (3 years, 3 months ago) |
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Quote:
starbones said: What a fuckin spaz of a reply that was.

$20 shipped with Prime. Goes as dead slow as I want it to and fast enough to blend. I run over 60 monotubs at a given time and need oodles of LC. You can cry that because it is cheap and from China it is going to be bad but for the price of these I will sit them absolutely next to any bodged together unit. I can keep a quart of LC on there barely turning just fine.
I look forward to your next wall of text telling me how impossibly wrong I must be for not hacking together a rickety contraption instead of spending the equivelant of 1.5 hours of minimum wage employment on a unit with an actual speed controller.
For the record..
I followed THIS advice and purchased THIS exact magnetic stirrir...
it's either gives me extreme speed or stalls out when trying for a slow rpm. Just like all the other cheap magnetic stirrers i purchased.
I'm about to build my own and use these fast as shit amazon stirrirs for when i need to mix up my lc prior to inoculation.
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pitriot
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Re: How to make a _good_ magnetic stirrer for cheap [Re: trippleblack]
#27002825 - 10/25/20 02:03 PM (3 years, 3 months ago) |
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Can you share the link to this? All I want it for is to stir and break it up before using to inoculate, so it sounds like it might work for me.
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GermanShaman
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Re: How to make a _good_ magnetic stirrer for cheap [Re: Blue Helix]
#27054892 - 11/24/20 03:46 AM (3 years, 2 months ago) |
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this looks great. I tried to make one using a PC fan but it spins way too fast.
I need to buy some magetic stirrers though. I tried cutting some metal rods but they did not work.
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