|
Some of these posts are very old and might contain outdated information. You may wish to search for newer posts instead.
|
Javadog
Continuing along



Registered: 05/03/10
Posts: 7,385
Loc: USA
|
Re: my 24x24 h14 hepa flowhood [Re: ohmatic]
#12629293 - 05/25/10 10:44 PM (13 years, 8 months ago) |
|
|
Quote:
ohmatic said:
Quote:
seti said: Isn't the rectangular hole you cut out too small to let all the air flow through the filter? So the sides on the hepa filter where there is no hole are essentially useless? Please fill me in.
<SNIP>
the hole just needs to be about the size of the outlet of the fan, i decided to cut it approx 0.5cm smaller than that in order to ensure a little overlap to get nice pressure in there - seals better.
Hey Ohm,
I am quite the noob, but in my research on flow hoods and squirrel fans I am sure that I read that squirrel fans should not be slowed by blocking the output, but that the intake should be blocked, in part, to reduce flow.
I think that I understand the concept here. I have a caged-fan type of rowing machine, and the way you reduce the drag when working out is to close the vents to the fan. This way the fan cannot interact with the outside air reducing drag.
The article that I am recalling suggested that blocking the output of such a fan puts extra load on the fan.
Now, I write all of this thinking that the percentage that you covered is very small and not an issue.
...but I just wanted to add to the discussion.
JD
P.S. I did a search and saw this, part of an iten description on Amazon:
"This squirrel cage shaded pole blower fan does not come with a power cord. It is a great all-around blower. You can reduce the CFM of the blower by partially blocking the intake, but DO NOT block the blower's output. That will burn the blower out."
-------------------- Boyd Rice told my brother that life is a corny pack of freesakes Myco-tek.org
|
ohmatic
searcher



Registered: 02/28/04
Posts: 6,742
Loc: europe
|
Re: my 24x24 h14 hepa flowhood [Re: Javadog]
#12629755 - 05/26/10 12:18 AM (13 years, 8 months ago) |
|
|
NOTHING is blocking the output, the overlap is simply for better sealing.
its far to small to block anything.
--------------------
MONOTUB tek HEATBOMB tek RIP #cultivation! ....can't associate? well FUCK U !
|
mainratte
humble

Registered: 03/23/10
Posts: 14
|
Re: my 24x24 h14 hepa flowhood *DELETED* [Re: ohmatic]
#12670491 - 06/02/10 02:07 AM (13 years, 7 months ago) |
|
|
Post deleted by mainratteReason for deletion: .
|
ohmatic
searcher



Registered: 02/28/04
Posts: 6,742
Loc: europe
|
Re: my 24x24 h14 hepa flowhood [Re: mainratte]
#12670789 - 06/02/10 04:56 AM (13 years, 7 months ago) |
|
|
i thin kyour referring to to agar, well the flow from above gets you one problem, you have got SIDES to the filter where the air has to pass, these areas can catch contams which would in return get swirld around.
if you work infront of the filter, like in my design, you dont have any sides to it and nothing to be blown around.
ill always be working in front of it.
--------------------
MONOTUB tek HEATBOMB tek RIP #cultivation! ....can't associate? well FUCK U !
|
mainratte
humble

Registered: 03/23/10
Posts: 14
|
Re: 24x24 h14 hepa flowhood - NEW DESIGN *DELETED* [Re: ohmatic]
#12673318 - 06/02/10 04:24 PM (13 years, 7 months ago) |
|
|
Post deleted by mainratteReason for deletion: .
|
ohmatic
searcher



Registered: 02/28/04
Posts: 6,742
Loc: europe
|
Re: 24x24 h14 hepa flowhood - NEW DESIGN [Re: mainratte]
#12676762 - 06/03/10 03:28 AM (13 years, 7 months ago) |
|
|
Quote:
mainratte said: what about yourself? isnt ones body not also a factor of getting some swirls back in or do the 100 ft/min compensate for that?
you cabn think of a "cube" of sterile air that is created infront of the filter.
obviously any contam introduced there, may be your arms or dirty equipment, is going to be present.
this is why i wash my hands/arms thoroughly and rub them with rubbing alcohol once dry.
it is advisable to also wear gloves, sanitised of course.
--------------------
MONOTUB tek HEATBOMB tek RIP #cultivation! ....can't associate? well FUCK U !
|
mainratte
humble

Registered: 03/23/10
Posts: 14
|
Re: 24x24 h14 hepa flowhood - NEW DESIGN *DELETED* [Re: ohmatic]
#12677340 - 06/03/10 08:24 AM (13 years, 7 months ago) |
|
|
Post deleted by mainratteReason for deletion: .
|
iluvfungi


Registered: 06/17/09
Posts: 1,488
Loc: Oakland, CA USA
Last seen: 12 years, 8 months
|
Re: 24x24 h14 hepa flowhood - NEW DESIGN [Re: mainratte]
#12682736 - 06/04/10 02:03 AM (13 years, 7 months ago) |
|
|
From what I've read; I see no point in the pre-filter for a industrial Hepa Filter. The reports stated that Hepa filters perform better after years of use. Regardless, a Industrial Hepa filter lasts 10 years or more.
|
bixo
Dremel Addict



Registered: 02/14/05
Posts: 388
Loc: The Autobahn
Last seen: 10 years, 9 months
|
Re: 24x24 h14 hepa flowhood - NEW DESIGN [Re: iluvfungi]
#12701942 - 06/07/10 08:08 AM (13 years, 7 months ago) |
|
|
Double-tap for the win. Hi Ohm.
|
Javadog
Continuing along



Registered: 05/03/10
Posts: 7,385
Loc: USA
|
Re: 24x24 h14 hepa flowhood - NEW DESIGN [Re: iluvfungi]
#12704136 - 06/07/10 04:12 PM (13 years, 7 months ago) |
|
|
Quote:
iluvfungi said: From what I've read; I see no point in the pre-filter for a industrial Hepa Filter. The reports stated that Hepa filters perform better after years of use. Regardless, a Industrial Hepa filter lasts 10 years or more.
This is good news....given that I intend to use mine only for clean work and not as a house filter.
BTW: my 18X24 came from Fungi Perfecti today. Whee!
(thanks to the forgotten poster who suggested the 18", and that it will help with spawn bags better)
Now, I have to find the best directions. (I think that other sites step by step process "first to attach the bottom, then the sides, etc" is the best approach that I have seen) I have no illusions that I will find blue-prints with precise dimensions to cut for this filter...
-------------------- Boyd Rice told my brother that life is a corny pack of freesakes Myco-tek.org
|
fastfred
Old Hand



Registered: 05/17/04
Posts: 6,899
Loc: Dark side of the moon
|
Re: 24x24 h14 hepa flowhood - NEW DESIGN [Re: iluvfungi]
#12705859 - 06/07/10 09:29 PM (13 years, 7 months ago) |
|
|
Quote:
iluvfungi said: From what I've read; I see no point in the pre-filter for a industrial Hepa Filter. The reports stated that Hepa filters perform better after years of use. Regardless, a Industrial Hepa filter lasts 10 years or more.
LOL If you've ever looked at any sort of filter after a year or so of use you'll know that they are clogged with cat hair, dust bunnies, and all sorts of nasty shit.
When you get enough organic material on your filter it will form a breeding place for contams and a storehouse for all sorts of shit you don't want. With a cheap prefilter you just replace it. When it's on your hepa you can't really afford to throw it out all the time.
No filter is perfect, and when you let a shit ton of bullshit built up on the actual filter that shit will continuously release spores and other bullshit, some of which will make it through.
So go ahead and not use a prefilter. When your flow rate drops and you start getting too many contams making it through you'll know the reason.
-FF
|
ohmatic
searcher



Registered: 02/28/04
Posts: 6,742
Loc: europe
|
Re: 24x24 h14 hepa flowhood - NEW DESIGN [Re: fastfred]
#12706754 - 06/08/10 12:12 AM (13 years, 7 months ago) |
|
|
Quote:
fastfred said: So go ahead and not use a prefilter. When your flow rate drops and you start getting too many contams making it through you'll know the reason. -FF
100% agreed 
thx for your agar collection btw +5
--------------------
MONOTUB tek HEATBOMB tek RIP #cultivation! ....can't associate? well FUCK U !
|
trypnotic
Stranger

Registered: 08/13/10
Posts: 6
Last seen: 13 years, 3 months
|
Re: 24x24 h14 hepa flowhood - NEW DESIGN [Re: ohmatic]
#13048624 - 08/13/10 10:05 PM (13 years, 5 months ago) |
|
|
is there a better way to seal the filters without siliconing them in?? would be a hassle when you have to change them.
|
RogerRabbit
Bans for Pleasure


Registered: 03/26/03
Posts: 42,214
Loc: Seattle
Last seen: 11 months, 3 days
|
Re: 24x24 h14 hepa flowhood - NEW DESIGN [Re: trypnotic]
#13048647 - 08/13/10 10:09 PM (13 years, 5 months ago) |
|
|
Weatherstripping. RR
-------------------- Download Let's Grow Mushrooms semper in excretia sumus solim profundum variat "I've never had a failed experiment. I've only discovered 10,000 methods which do not work." Thomas Edison
|
trypnotic
Stranger

Registered: 08/13/10
Posts: 6
Last seen: 13 years, 3 months
|
Re: 24x24 h14 hepa flowhood - NEW DESIGN [Re: RogerRabbit]
#13048886 - 08/13/10 11:10 PM (13 years, 5 months ago) |
|
|
thx RR, one more question, what do you think would be the best material to use, wood harbors contams right? any suggestions?
|
Alkaloids
3,4,5-trimethoxyphenethylamine



Registered: 11/15/98
Posts: 743
Loc: pubis mons
|
Re: 24x24 h14 hepa flowhood - NEW DESIGN [Re: trypnotic]
#13133475 - 09/01/10 12:28 PM (13 years, 4 months ago) |
|
|
trypnotic Unless your relative humidity is very high in the room you work in you shouldn't have to worry much about wood getting to bent out of shape. (ha ha i had to do that)
If you start with good clean wood there should not be any problems. If you are worried you could always apply a bright white cleanable paint over the wood before construction.
Great thread by the way. I'm waiting to build a new flowhood as my last 2X2 ft one got confiscated by LEO. Love 'em. 
I like the folding door/cover design. Very space efficient.
--------------------
|
OrangeBarrel
Stranger

Registered: 08/26/10
Posts: 19
Last seen: 2 years, 1 month
|
Re: 24x24 h14 hepa flowhood - NEW DESIGN [Re: trypnotic]
#13133767 - 09/01/10 01:33 PM (13 years, 4 months ago) |
|
|
trypnotic -
If you dont mind the additional weight, Melamine plywood is a nice option.
|
trypnotic
Stranger

Registered: 08/13/10
Posts: 6
Last seen: 13 years, 3 months
|
Re: 24x24 h14 hepa flowhood - NEW DESIGN [Re: OrangeBarrel]
#13199663 - 09/15/10 02:30 PM (13 years, 4 months ago) |
|
|
http://www.rabbitair.com/BioGS-SPA-421A-Ultra-Quiet-HEPA-Air-Purifier.aspx
hey guys could check this link out and tell me if this type of air purifier would be effective enough for our needs. I've been lazy trying to build my own and this is practically the same amount i would spend anyway. I would really appreciate some feedback, thanks.
tryp
|
RogerRabbit
Bans for Pleasure


Registered: 03/26/03
Posts: 42,214
Loc: Seattle
Last seen: 11 months, 3 days
|
Re: 24x24 h14 hepa flowhood - NEW DESIGN [Re: trypnotic]
#13199980 - 09/15/10 03:30 PM (13 years, 4 months ago) |
|
|
It will help to control dust indoors, but don't expect to use it in place of a flow hood. I have a similar, but lower-end one I run all winter when the wood stove is going because it helps keep ash, pet dander, and dead skin cells down to a minimum during the winter when we don't have the windows wide open for air. I always shut it off and close the doors to the small room I use for sterile work when I'm running the flow hood though. RR
-------------------- Download Let's Grow Mushrooms semper in excretia sumus solim profundum variat "I've never had a failed experiment. I've only discovered 10,000 methods which do not work." Thomas Edison
|
ohmatic
searcher



Registered: 02/28/04
Posts: 6,742
Loc: europe
|
Re: 24x24 h14 hepa flowhood - NEW DESIGN [Re: RogerRabbit]
#13200268 - 09/15/10 04:28 PM (13 years, 4 months ago) |
|
|
roger, doesnt that "air purifier" get insanely dirty all time time ? after all our is is laden with stuff.
--------------------
MONOTUB tek HEATBOMB tek RIP #cultivation! ....can't associate? well FUCK U !
|
|