what mat'l for oiled foam air filter?

[ramblerman]

I'm working on two projects (a bike and a car) for which I want to build my own oiled foam filter elements. However, I can't find any specific information on appropriate foam density or if there is a specific quality of foam most appropriate to use for air filtering.
Obviously, my concern is walking that line between too much restriction and not sufficient filtering, especially since I live in the dusty part of the country (sw Kansas).
The restriction component is important, since I would hate to negate or mask the positive effects of performance modifications by choking the engines.
Anybody have a source for infomation on this, so I don't have to do my own testing?

 

[Peter7307]

ramblerman,
The only information I have been able to find is on this site :

http://www.theairfilterguide.com/s/foam_air_filters

which may be of use for your intended application.

The general material seems to be open cell polyurethane.

Please email or post whatever you find. Iam also interetsde in this topic.

Cheers , Pete.

 

[unclesyd]

Make sure anything you use is open cell.

Normally there are some cell sizes and foam volume requirements also.

 

[ramblerman]

Well, here's what I've found so far. Uni Filter sells bulk filter material

http://www.unifilter.com/online catalog/accessories.html

but they don't seem to offer guidelines about (area of foam)/(cfm) or any real definitive information about their foam.
Yes, I know I'm looking for open cell polyurethane foam, but all the foam I can find that meets that description is sold for cushioning, so they describe their product as "soft", "medium", and "firm." Since I've started looking for information I came across a neat technical paper about this

http://www.foamex.com/technical/pdf/FS_MEC4.pdf

which gives me good technical data from which I can extrapolate appropriate filter requirements for my projects, but it does little to help me define what the specs are on the foam being sold at the local craft store, or where to find foam that would be specs-defined. I'll keep looking.

 

[bobqzzi04]

Why do you wish to use oiled foam? I'd be much more inclined to use the paper element from a production car.

 

[ramblerman]

Three reasons:
#1. Oiled foam is superior in flow characteristics to cellulose (paper) as soon as the paper element gets even the slightest use. Oiled foam is equal to oiled cotton gauze in flow characteristics, and is far superior in dust apprehension.
#2. Both projects (car and motorcycle) will have been modified extensively when I'm done with them. The place for an off-the-shelf filter element will not be there.
#3. Because after I have fabricated parts and scrounged parts, both in an attempt to go beyond "good enough" and reach a point where I can say that I have the most suitable part for each function, it just doesn't seem right to slap on a "good enough" air filter.
Call me a fanatic. Call me a perfectionist. But these two projects are therapy, not work. In both cases they will be the best I can make them.

 

[unclesyd]

Two suppliers of different types of filtration foam. The one in England will give you some term search for.

http://www.foamtechniques.co.uk/

http://www.foamex.com/technical/filtration.php