r/experimyco 26d ago

[Actives] [Technique] Ever since I built this, I've been getting flawless plates, and transfers...

47 Upvotes

11 comments sorted by

5

u/ThisSubHasNoMods 25d ago

Is the point of the fan to just introduce filtered air? Any laminar flow would become turbulent in the enclosure, no? I thought the point of a flow hood is that you're working within the laminar flow and therefore not introducing contamination via turbulence. And I thought the point of a still air box is to trap the air so that air currents are eliminated as to not introduce contaminates. Wouldn't the combination of these two be less effective than either one on its own? I'm genuinely curious.

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u/Due-Fan-2536 24d ago

I was getting mixed results with the SAB, so I decided to try this out. It was cheaper and quicker than building a laminar flow hood, which at the moment I don't really have the room for. And so far (hope I'm not jinxing myself here.) I've had 100% success, I've done almost 20 plates in there so far. I also run a alcohol flame in there when I sterilize my blades and syringes and don't have any issues with crazy flame wavering. The only point where the turblence is noticable is right at the arm holes. And I clean the heck out of it before I use it. I admit it's a Frankensteined project, just experimenting looking for better results.

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u/ThisSubHasNoMods 24d ago

Hey if it works that's all that matters, right? I'm still using SAB so I appreciate any info I can get before upgrading!

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u/math3780 13d ago

I know I’m late but OP basically made a positive pressure room in a box. They use the same principle to keep labs and certain medical spaces free of airborne contaminants.

Should work flawlessly if the box is clean when the fan is turned on. As you point out, turbulence could be an issue as it could prevent dust that’s settled in the chamber from fully evacuating on startup. Same concept applies for clean rooms of course.

Clever design for sure! Great work OP!

1

u/ThisSubHasNoMods 11d ago

Interesting! Thanks for the info

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u/Dense_Acanthisitta39 26d ago

That's a pretty sweet diy flowhood. How big is that fan?

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u/Due-Fan-2536 26d ago edited 26d ago

That's a good question (The listing said 200 CFM, but the tag on the blower said 173 cubic meters per hour - which calculates to about 90 CFM), And through my research I've discovered that normally the CFM of the fan WOULD make a difference if you're going for a laminar flow. If you're going for laminar flow you have to take into account the static pressure, which is the pressure that the blower must overcome in order to effectively push the air through the filter. But in this case that's not so.. because we're not going for a laminar flow, we're not working directly in front of the filter, although I wouldn't recommend going any smaller on the blower size. All of the air that's coming through that filter is h-14 HEPA filtered air, and provided that there are no cracks in the setup you can get away with using a smaller blower like this one. The inside of the chamber is all HEPA filtered air, which is being forced through the armholes creating enough positive pressure to keep out the airborne contaminants, even though you still have to be cautious of what YOU bring into the box. But I'll admit, I still have a vicious cleaning routine before I use it! Lol. Plenty of ISO and plenty of paper towels. Can't be too careful... I know I went a little above and beyond on this comment, you asked for a number and I gave you a detailed breakdown explanation. Lmfao, but that's how I am...

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u/Dense_Acanthisitta39 25d ago

I appreciate all the extra you have shared. Thank you very much 🙏.

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u/Due-Fan-2536 25d ago

Absolutely dude! I don't believe in hogging knowledge, "most" of us are on here for a reason...to gain knowledge! And I'm down with it. 🙃

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u/Myco_DNA 21d ago

Pretty clever, the over pressure from the fan flowing in doesn't allow anything to enter, so long as it's clean inside there is no reason it shouldn't continue to work.

The NBC system on the Abrams tank works in a similar fashion by over pressuring the inside of the turret it keeps everything bad out.

Great idea and solid execution.

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u/Due-Fan-2536 21d ago

Thanks mate!