I am helping an Amish neighbor who wants to build a wood-fired gasifier to produce fuel for a five or six HP Honda gasoline engine at his wood working shop. He might also fuel an eleven HP Honda engine there as well. He does not use a computer or watch videos (at least not yet) so I am looking for written plans I could get or print from pdf versions. He wants to reuse or repurpose items he has available. He works at a saw mill much of the year and has access to free oak, cedar, pine, and sometimes other wood slabs and chunks for fuel. Who has plans for building a good unit that would last a long time? Or do you have suggestions for a better path for him to follow? Steve Collins
Small engines usually use charcoal gasifiers. I would look at Gary Gilmore’s ‘Simple Fire’, at least to start with. Library / The Simple Fire | Drive On Wood!
Steven I linked to you in another thread for a charcoal gasifier, but if they already have access to slab wood I’d say they should put in the effort for something like a Ben Peterson gasifier. You can buy his book “The Wood Gasifier Builder’s Bible”. Very good book, very in depth and it’s a well proven design.
Cody, I will look into that book by Ben Peterson, “The Wood Gasifier Builder’s Bible.” Steve Collins
His plans are for 500cc and larger, Bens gasifier is not designed for this small of an engine.
That saved me some time and probably some money. Thank you. Steve
You mentioned in the other thread he doesn’t want to make charcoal, there are other small engine raw wood systems other than the Ben Peterson. For the 6 horsepower, probably 196cc Honda, charcoal really is the way to go in my opinion, but yes Matt is right, Ben’s design is 500cc up to V8 generator units though it’s been used on trucks as well.
Bear in mind no matter which way you go there’s a decrease in Horsepower/Kilowatt output.
Do you know who has some of the others (not Ben Peterson) for 196 cc Honda size?
The only one I would know of is a Northern Self Reliance style gasifier, but I don’t think Stephen sells them anymore and I don’t know if he sells any blueprints. He had a rough guide to make the hearth zone.
This just more or less explains his specific form factor, it doesn’t give hard measurements.
Using the formulas provided by Dutch John you could put two and two together to make a small enough gasifier.
With the quick math I did using a Predator 212cc engine I’m getting a 1.375" restriction for that engine at 3600 RPM. Awful small, I can see why Stephen Abaddessa uses that 4th nozzle to burn right at the restriction.
I’d say if you were to copy Stephens design with the 4th nozzle, I’d round up to an even 2" restriction for flow. Or keep a conservative size of 1.5". That 4th nozzle will be directly burning at the choke point in the hearth and ensure tars are converted.
For “trouble free and lasts a long time”, especially for small displacement, single cylinder engines, charcoal is king. The Gary G. Simple Fire design is the beginners ticket to sucessful, self-taught small engine wood gasification. there are numerous ways of making charcoal.
Your friend does not have a computer, but why would they not want to make charcoal? It is very useful stuff, even for the garden, water filtration, and outdoor cooking.
Dutch John has a lot of material on his website, many still pictures in the “Micro Gasifiers” section. He also goes out of his way to explain they require attention to every detail, like wood chunk size, etc. and are “fussy”, and he almost tries to talk you out of the idea entirely. He gives all the design basics of what he built, there are still areas of mystery.
Northern Self Reliance (Stephen Abidessa) gasifiers run on hardwood pellets, uniform size fuel.
Micro Gasifiers (woodgas.nl)
Not for a wood gasifier. Best of luck getting one to work. I spent 8 years and over a million dollars trying. Thats all I have to say on this subject.
I agree when it comes to the smaller single cylinder engines, charcoal takes the headache out of the equation. @d100f really showed how he can set it, forget it and rely on it daily.