Build Your Own Laminar Flow Hood for less than $100 (really WORKS!)

Full flow hood build write up and links to items used: https://gordotek.org/laminarflowbox To get access to ALL CONTENT please visit https://gordotek.org/ and also check out my free discord (all of my content is FREE I don't use paywalls, support only if you feel you have benefitted and can afford to do so). Before asking a question, please read the FAQ: https://gordotek.org/faq Due to corporate censorship I had to start hosting everything on my own servers, should have done that from the start! Credit to The Efficient Engineer (“Understanding Laminar and Turbulent Flow")    • Understanding Laminar and Turbulent Flow   More about Reynold's number: https://en.wikipedia.org/wiki/Reynold... Q&A Is it easy to change the filter?  The manufacturer says it has a 4000 hour life, even if you cut that in half, it's probably still a lifetime of use for just mycology work for most people (remember you don't leave this thing on and running all the time).  But yes if you had to replace it, it should be very easy to do so, the silicone sealant is like rubber cement, you can just pull the old filter off and scrape away the leftover sealant and put the new one in.  Likewise the tote lid will still come off pretty easily if you pull on it hard enough. The whole replacement can be done in about 15 minutes. Can or should I add a pre-filter?  You could add a pre-filter if you want, you could do something simple like stretch a cotton t-shirt over the fan intake and secure with rubber bands or zip ties.  Or you could use the carbon filter that comes with the HEPA filter.  Its up to you.  The HEPA filter is supposed to be good for 4000 hours, if only used for mycology work, that could be a lifetime for many people.  But as noted above, the HEPA filter is not hard to replace if needed, it's basically a 10 minute job, can pull it off and scrape away any remaining silicone sealant, then put the new one on. I noticed some air coming OUT of the fan area, is that normal?  First please make sure that you installed the fan in the correct direction because if you did it backwards the flow box won't work at all. But that said, yes, It's actually normal and expected for air to be flowing both in and out of the fan like that, this means the pressure has reached an equilibrium which is exactly what you are looking for, nice even pressure inside the box producing laminar flow out the front. Can I install the fan in the back pointed directly at the filter?  No, you don't want the fan pointing directly at the filter, this would cause uneven air pressure on the filter, you want it on the side and you will just allow it to build up equilibrium pressure inside the box (I probably should have explained that in the vid). Is it an improvement to add a top and/or sides to the front part of the flow box?  No, sides and tops are counterproductive, they create a vacuum and unfiltered air must then be sucked in to fill the vacuum, creating turbulence (the opposite of what you are looking for).  You don't want sides or tops but its even worse if you direct the output into a still air box which for some reason many people seem to want to do (this completely defeats the purpose of a laminar flow box, you will have nothing but turbulent air). Can I use the 6" or 4" version of that fan instead?  The 6" model will work, the 4" will not.  The HEPA filter requires around 200CFM but a little more is preferred, keep in mind that as the filter ages, it slowly clogs, requiring more and more CFM over time to produce the same flow rate. Does the design really produce laminar flow?  I've seen some critics saying the design doesn't produce laminar flow, but they are wrong. The design does in fact produce laminar flow when properly tuned, you can see this visually with a proper flame test (as shown in my vid at 18:53) and you can also see it with a smoke test, even though I didn't do an intentional smoke test in the vid, there IS actually an accidental one, if you blink you could miss it, but it happens at 25:48 as I'm sterilizing a scalpel that is smoking from the induction coil. As you will see, absolutely beautiful laminar flow! Compare this to other videos of smoke tests on laminar flow boxes. Most of the critics disappeared after hundreds (if not thousands) of people built these with absolutely fantastic results, there is no question that the design works well, many have called it a "game changer" for them. I think its funny that initially there were skeptics despite the fact that I show the design works by using an expensive laser particle counter, flame test, open agar plate test, and a complete start to finish grow with it. Producing laminar flow is not as hard as many once believed. But you do need a legit HEPA filter and capable variable speed fan.