Joni , Have you considered trying a oil bath filter ? i would still be looking at a pure woolen filter made to stretch over a frame almost like a tent that would drip dry as its being used i bet .
Dave
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The main criterion for the quality of gas for a wood-burning generator, in my opinion, is the transparent and invisible gas at the entrance to the mixer. Denim suited me according to this criterion, but there is no sheep wool fabric (the weaving of threads is large enough, which leaves large holes for gas), it is also unsuccessful to use fiberglass. In general, either the fabrics are very dense or vice versa âŚ
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JO; I donât have time to look up your drawing ( you know how busy I am 
). I know, (I think) you donât have a grate, but doesnât your fire tube extend down below the restriction to give a âreductionâ zone? The bottom of the ash hopper, doesnât that act like kind of a grate in that it holds the coals up in the âreductionâ zone?? TomC
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Yes, you pictured it perfectly.
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Joni,
If I can get some thick wool fabric I want to try it for filtering. I understand that wool does not absorb water like cotton and therefore will not create the resistance to gas flow that wet cotton does.
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Dear Joni, dear Jan,
thank you for your answer. As always there is a learning curve of own experience behind a good working system.
Thanks again for sharing it with us!
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TomC,
Ha! In fact, many people think like you, but I ask them a counter question âwhy is the gas burning and the car is driving on a freshly cleaned ash pan?â if the ash pan is empty and the operation of the motor has not changed, then the question of unnecessary zones and details becomes obvious ⌠
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Steve,
I dare say that finding woolen fabrics that meet our needs is not worth the effort, and using it will not bring you the expected results.
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Joniâ In my case, I use a grate. It holds the char up in the reduction zone. The volume below the grate to the bottom of the ash pit is just to catch the âslipâ char off or through the grate. In theory, the char should sit in the reduction zone until all of the C is gone and only a fine ash remains. Unfortunately, I have always had some char that as it gets small, falls off the edge of the grate or goes through with the gases and falls to the bottom of the ash pit. TomC
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Joni,
Just saying if you want a cloth filter for damp gas, I think wool is probably a better choice than cotton. It can also tolerate more heat.
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Well i think the problem that Joni is seeing with my suggestion of using wool is that he is thinking of a woolen knitted jumper and how easily it would be for everything to pass through that , but i am not talking about knitted material at all , the wool that i use is still in its raw state and just been carded and so looks like fiber matting it has yet to be spun and makes a fantastic filter here is a photo of my wool
Dave
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Dave,
I have never seen such material in my life ⌠
Donât forget where I live
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Hi Joni , i am no expert , but i think all this is , is the wool they shear from sheep and then it goes through a prosses to remove bits washing and combing i think this is after it has been combed before it goes to a spinning wheel to make yarn , if you look at this woman she is carding the raw wool to make it into a batt ready for spinning , this is the stage you want to try and get some wool if you can
Dave
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Felted sheepâs wool like in a hat material will give the densest packing flow filtering. Maybe too dense.
Woven 100% sheepâs wool fabric comes in many densities. Menâs dress slacks; to much more open woven coat and blanketing fabrics.
No matter. A 200 to 400 mm cut stack will filter.
Ha! And be light weight.
S.U.
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Stive,
I think it might be good, but this design and materials donât suit me âŚ
and in fact I have already experienced it
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Good.Good.
Try is all we were asking.
We honor freedom of choice above all. You are respected for your choosing.
So onto manmade fabrics. Solid rod fibers.
True, rare now, hollow fiber, natural Linen fabric has the best rotting resistance. Was never as popular for clothing or sail making because tight folding for overlapping seaming causes the fibers to break.
Regards
Steve Unruh
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I have also used those Micro cloths with good results and Kristijan uses a towel material that he rates highly .
Dave
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Ok now back to your gasifier.
I am sorry l have been buissy lately and wasnt able to pay close atention to everything that is going on on the site but if l remember right you evacuate the hopper gases/steam from your gasifier via exhaust venturi right?
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Hello Joni .
No worry about offending me 
I welcome and appreciate any constructive criticism and wish we lived close enough to meet . I would really like to ride in your car and would like to offer you a ride in my old truck 
Thanks
Wayne
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