You mean like this, right? Like a classic Inverted V.
And then put a restriction ring on the top to let it develop more ash?
3 Likes
Yes, exactly, but I’m also a beginner, so JO or Kristijan can say what they think.
3 Likes
With woodgas we are all beginers. You always learn, and usualy in the end you found out people figured this out 100 years ago 
Jans idea and your skech is exactly what l wuld recomend too. Wood gasifiers realy are simpler–>better. This will make a long lasting good performing gasifier. Just find a thick restriction ring for some flywheel effect and thats it.
6 Likes
There’s an expression that y’all might know of, “If it was a snake it would have bit me”
That pretty well sums up my imagination in design. I’ve been staring at the Inverted V diagram for days now and didn’t see the naturally occurring V from the golf cart rim 
4 Likes
Heres a few bearing races and what looks like something from an automatic transmission, and some kind of spacer tool.
1 Like
I have two races that are almost identical and measure about 3.5" at the tightest.
Should I weld them together to make a long restriction or just one should do fine?
1 Like
One thing I forgot to mention is that on the side Jan suggested I use as the inverted V has the valve stem for filling the tire. Should I just weld that bit shut or let the ash fill it up and not worry about it?
I’m getting closer to just going grateless and not encasing the bottom propane tank. Just weld in my gas exit high up and a cleanout pipe near the bottom.
This is most definitely not to scale, just the general layout of what I’ve been describing.
I will be using the old handles from the propane tanks to make feet for the bottom of the reactor.
The hearth will be lower in the base to keep ash and char from flying up the gas exit as much.
1 Like
I would weld the holes tight, otherwise I would wonder if it was the fault if it does not work.
Would also put in some iron across about 3-4 "under the fire tube so I had the opportunity to put in a grate.
6 Likes
Im with Jan on all of it
2 Likes
Well since you are now talking actual raw woodgasifing I feel competent to comment.
You are a reader and studier CodyT.
That is good.
You do build and engine use - that is better.
Grates. The published information talks a lot about grates.
Not one publication . . . not a single one, actually classifies grates by function.
Why a grate/roost/grid at all??
To hold up the char bed so the individual particles held close to each other, active, and in a defined zone.
Only secondary is it to separate out the non-active exposed cell walls mineral ash.
In the past for mobile gasifer it was always Flow-Thru grates. This means ALL of the produced gasses, un-converted char, and exposed ash (and any made melted clinkers) was to flow-thru the intentional made grate openings.
It would be easy to say these all are whole edge to edge perimeter grates: Imberts; Vesa Mikkonen; GEKs.
But then there is MaxG’s “bird-cage” vertical V-bars grate. All must flow through.
And some perimeter to the edge grate system have the produced gases extracted ABOVE the grate.
Then there is the By-Pass grate. The grate plate/plain/surface intentionally smaller than the lower hearth chamber.
To intentionally allow produced gasses; and char particles; and even some ash to spill edge over and out as needs be: the FEMA’s; MotherEarthNews; the WK’s; BenP’s; Joni’s 8.0-10.0.
Whether it chain/links/rod hangs down. Or is up from the bottom post supported . . . it is the intended function that makes it a by-pass grate.
Now to me even more telling is do you intend to do a lot of after gasify sorting and separating of blown thru soots, char and ash . . . . The classic Imbert’s with their three maintenance ports: two above the grate and one below the grate.
And ALL grate-less; like the Mukunda/IISc’s. And the by-pass types operated as much-slipped/grate-spilled percentage systems.
Or are you going to go with as much as possible 100% of all in-system made char being to gas converted in one pass through the system. Brandt’s and Joni’s. Others.
(It will depend greatly on the actual wood you use: which system, you will evolve to easiest using!!)
Steve Unruh
6 Likes
The trees I have on the property are various little trees like Poplars, some Oaks that have yet to be cut down in the old growth, what would have been tree farm white Pine, scattered Maples and black Walnut. In the fall I’m going to start my coppicing project for the long run, we have lots if piddley small trees that could chunk good into small fuel.
Pine is the most plentiful on the property and is now growing wild since we clear cut 8 acres. Most of that acreage is growing back a mix of pines and hardwoods and briars.
In the meantime I have about 4 big oaks that were dead standing and I can chunk those.
I am at an impasse for either making a full birdcage with vertical and horizontal V bars, or making a round flat V bar grate by welding angle iron to one of the propane tank foot hoops.
Also not sure if i want it to be a fixed grate or a swinging grate. Chain suspended seems to be the safest bet for either of those designs.
The air jacket will end right where the highest portion of the Inverted V sits inside the burn tube. So that does leave me with some room for either of those grates and would be too high up for a grateless system.
I’m appreciating everyone’s input and taking everything into factor.
3 Likes
I looked at your sketch, it looks like you draw the nozzles far down in the fire tube, they usually sit as close to the extension to the wood container as possible, if you look at Jonis or JOs or my gasifier. I think it is because the wood becomes charcoal and decreases in size then.
2 Likes
That’s good to know. I wasn’t sure to place the nozzles high or low on the system. So I guess in that sense my nozzles would be just about at the top of the tube, going up at a slight angle. This would give me a pretty long char reserve like a WK.
1 Like
I’m also unsure of that, wondering if it can not be too small particles so there will be a stop in the fire tube.
Should be some reason for the dimensions of the drawing.
2 Likes
I’m tempted to add one very small jet near the bottom like Abbadessa does with his units and another fellow on here that I’ve seen in a topic by Kristijan. I know others have done double row jets but two in particular just use one single bottom jet.
I just don’t know if that would ruin the build.
I’ll just stick to basics.
1 Like
I’m glad that I have a few ideas that I’m dead set on. Copying Joni’s hopper juice venturi removal, I have an exhaust tip I can weld a venturi into for that. And the heat exchanging core.
1 Like
Heres the rings I’m talking about from the feet of the propane tanks. I could weld the angle iron on the underside of the ring, and I already have holes to put the chains through. They are a little bit smaller than the golf cart rim that the inverted V hearth will be made from. Would that be a bad thing?
If I were to go this route I would have it on short chains so they would still have some wiggle room, but wouldn’t really slip that much.
1 Like
Going to the scrapyard today because I finally have a day off thanks to taco bell food poisoning! 
I’m going to try to find some more drums and hopefully another 20 gallon one like my hopper. Maybe I’ll get lucky and find some 16 gallon grease drums too.
2 Likes
For the cooling rails I’m thinking of either a continuous single shot running to the filter, or to just copy the WK type cooling rails but with less parallel pipes. I think I would do just fine with two in parallel the whole length.
My Mazda doesn’t have the nice post holes like larger trucks have so I’ll either attach the rails to my aluminum tie-down attachment or fab up a way to clamp it down.
For the filter I’m thinking of it being half hay and the upper half a bag filter.
1 Like