Homemade Air Cleaner

[BentRod]

There is a way to test to see if the volume of air flow will be the same.

to test:

- clear pipe. diameter isn't really important, read the instructions and decide for you self. The longer the better.

- close (but not tight) fitting ball or plunger to go inside the clear pipe. you want some mass here. ping pong balls are probably a no go, but then so are lead balls.

- section of your stock foam that more than covers the bottom end of the pipe remember air can flow out the sides of the flow section. most Ideal is if you cut out a puck of foam with a good fit to the inside of the pipe, and then rig it so as that it will not fall out the bottom (use common sense/ducktape here)

- stop watch

put the foam in one end, your ball/plunger in the other, and time how long it takes for the ball/plunger to fall. If the rate of decent for each foam in the same, then the air flows match.
Foam density isn't really an issue, because you can probably vary the thinknesses to match the air flows.

eventualy this will be what I do so i can make my own pod filters.

[Guest]

Well, I'm no chemist but tested out the Jo-Ann foam (originally for the seat) by soaking a chunk in a gas-oil mix for 12 hours.

I worked in the tire and rubber industry. The standard test for solvents for solid parts (not foam) immerses the part for x hours, and compares the physical properties before and after immersion. Some such properties are hardness (Durometer), modulus of elasticity, tensile strength and ultimate elongation. A less sensitive test is swelling. If the part doesn't absorb any solvent, it probably isn't affected by the solvent. Swelling can be measured by weight or volume. It would be hard to do this with foam. And I wouldn't be impressed with a 12 hour test. The filter will be exposed to gasoline fumes for a couple of years at a time.

Why is it important to use something other than a UNI foam sheet? UNI foam isn't very expensive compared to the cost of an air filter. The foam being considered comes in much larger sheets than anyone would need for an air filter. I wouldn't even consider buying foam that hadn't been tested in an industrial lab for solvent resistance.

[Nerobro]

The uni foam is $13.