Thanks Rindert and Hans - that’s great information. I already have a 30 gallon retort for making biochar for the garden- this system you showed me seems even better as the fuel becomes the product!
Im well aware of the tar issue after years of coaching my customers to not shut down the air fully when using crap wood in my woodstoves!
My intention- starting today, is to build a down draught reactor with ceramic nozzles and cook pot. Ill run fan assisted and cooled through an old oil- fin radiator and cyclone. then a large hay filter Ill spend as much time as needed just warming up the yard each evening until Im happy with my flare - then Ill progress to running my 20hp genset and splitters, chippers and finally- my V8 Landrover 110.
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Here’s a link to your channel, Tiny House and Off-grid Resources.
Found out I’m already subscribed to you!
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For your small engines build a charcoal unit. For your V8 build a wood gasifer. Use the char from your big one to run the little one.
Small scale wood fueled systems dont work all that great. They are subject to flow issues and small engines dont pull the volume to sustain tar cracking temps. These issues combined just lead to frustration and tar. You can not filter tar with the filters we are using for engine running. Producing wood fuel is not any easier than making charcoal either. Your labor, time, wallet and your sanity is worth more than that wood you are going to burn to make charcoal.
If you want to add creativety then shift it to charcoal production. Make it easier, make it useful, make it more efficient.
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Yes yes yes!- Ive watched so many of your videos! I agree completely re: charcoal
am I to understand that a cyclone is not needed with charcoal?
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It’s not worth the trouble if you give your filter enough room for the bits to drop down. Simple as.
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Welcome Stu.
Just wanted to show this Don Mannes unit. A good way to start.
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Hi Stuie , and welcome along , I hope we are giving you plenty of idea’s on where to start ,
I had a look at your YouTube site and started watching your "Build a Powerful Branch Chipper from a Ride On Lawnmower? part 1 & 2 but then saw no further development of the chipper have I over looked part 2 onwards ?
I am across the ditch from you in sunny Melbourne so if your ever this way you are more than welcome to pop in and see some machines running on wood and charcoal making power for my house and mens shed , there is also a closer neighbor of yours and he has a YouTube channel you will enjoy .
Have fun and cant wait to see what you end up doing .
Dave
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Hi Dand B- yes Ive watched MrCnCmachining, Just yesterday I think, showing his heavy stainless steel reaction chamber. Mine will be two flower pots set in pumice cement- far cheaper and will just lift out if it cracks up
re my chipper- Its sitting under a cover waiting for a big dose of machining. and I dont have the money for it just now. Ive got several big trees so I have to get it finished. two large side plates and the chipper flywheel will cost heaps too. the design is all sorted I just have to wait for money.
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Hello Stuie and welcome to the site. You will feel right home.
If you plan to start with charcoal, the thing is that its so simple that most complications usualy just make things worse.
Going downdraft is a good idea indeed, but to get the feet wet a simple 20l bucket with a clamp on lid made in a Simple fire gasifier will work best.
Usualy with charcoal, everything just works. As long as one cruicial parameter is met: right charcoal size. Wery important.
I (and l think preety much all here) tend to stay away from cheramics thugh. Nozzles crack and melt, slag clings to them… and the hearh similar. If insulation from intense heat is what you worry, fear not. Ash will form naturaly in a gasifier to form what we call an ashcone. This is what insulates the heat, protects the metals and seals the hearth from unreacted gases passing trugh.
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Well Its only been 4 days and my downdraught charcoal/wood gasifier is over half made! All the main parts have been scrounged up. feed hopper, blower. reactor housing, cyclone heat exchanger and filter bucket. Ive made several sets of pipe flanges, lids, grate, tuyere, air nozzles and brackets hinges mounting plates. Its all been painted and is drying in the sunshine. Its been fun getting into a bit of design/ development work. Theres a lot of similarity to my woodstoves and many of my stove components are finding use in the project, door seals, hinges, hi temp cements and sealers, hi temp paint.
This evening Ill bolt it all together and post a photo or two for your comments before I commence the plumbing. First fire up should be next Thursday. If I can get all the pipe work. Easter has got in the way and everywhere is closed for 4 days
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Now I can get into the fiddly bits. I like fiddly bits. The water drip, grate shaker and all that plumbing. Ive got two 1200C pyrometers that Ill connect up later. Im waiting on weldable black pipe fittings for the hot side and the air intake and stainless for the 5 port burner. PVC valves and some more bends to get the filter bucket connected after I get that and the cyclone mounted My cyclone has the ubiquitous pickle jar on the bottom and I have a baked been tin on the flare, so it should go well
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With burner you mean nozzles?
If so, a word of warning. Generaly its best to stay away from stainless in the hearth itself. It actualy has a lower melting point thain carbon steel and much lower heat conductivity so the tips will ruin faster. Best by far is high carbon steel, ideal material are deep hole rock drillbits.
Edit: best out of the more “clasical” kinda materials. Tungsten and other exotic things are a nother story
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Sorry for looking like a smartass, but l think you found out by now most if not all members here only try to help with experiances and prevrnting headakes.
This sayd, your flower pot idea is interesting but it might cause problems. In this area the heat is in the clay melting zone. But thats not the biggest problem, slag will love to cling on to it and when you try to extract slag peaces lm afraid it might shatter the pot.
Good news is the gasifier will work as is even without the pot. Ash will bind together over time to form a “pot” for you, tha ashcone. It is self repairing too. Anyway, will be interesting to see how the pot performs.
Since you bit the bullet and went straight to the downdraft, you now dont realy need a water drip. You can add the water directly to your charcoal, about 15% by weight. This will be self metering, cool the reaction, give you hydrogen and eliminate dust when handling fuel. Generaly water injecion is only used in updrafts since there the charcoal must de as dry as possible.
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Save yourself a lot of hassle and thoroughly test for any possible air leaks. Even the smallest will stop you from making useable gas. Also the things Kristijan said. Nice looking work.
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Stu,
Looking forward to the testing! Yes, that clay pot may give an interesting result, Try it and see! Good news is they are cheap, and can be nested to give more layers. Use lots of ash around it, who knows? 
We can take bets on how long the label stays on the bean can. I approve!
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Thanks everyone- I dont know how to “quote” people or do multiple quotes yet but I appreciate all those above comments. Ive been making my own refactory cement for rocket stoves using pumice, woodash and plaster. Ill pack that around the pot and yes I wondered about stacking them. - Im quite prepared for burned up nozzles- Ive got 3 forges… My main Idea is that parts are serviceable without having to get the grinder out. Kristijan - thanks for making me aware that I got it wrong about the water injection. that makes things simpler.
Its 5 am - Im off to pick mushrooms and go to the farmers market for the day. I live in the future- It’s Saturday here.
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When you get around to it tell us us about your forges and whatever blacksmithing you do. We here like all that kind of thing.
A thread for blacksmiths by Jesse North
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Well Its looking real interesting cant wait to see it ready to run .
roll on Thursday .
I give the label 30 seconds after first lit , for the Woolies home brand label , had it been Heinz then maybe 45 seconds too burn up 
Dave
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A quick update: Easter weekend is done and dusted here- I live in the future remember?
Im now waiting on courier deliveries for furnace fan, pipe fittings, ball valves, exhaust pipe bends.
This coming week will be a flurry of activity in the stovery. There’s all the plumbing to do, then insulate the reactor, wire up the fan and the pyrometers. then wheel it outside for a burn.
I have to figure out how to get the drive to the wheels
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Looking at your setup. After your gases are cooled they will go into the plastic 5 gallon filter bucket. Correct? It is possible the gasifier might get hot on the lower part of the barrel. I would put some insulation between the two. Or move the filter away from being to close. You do not want any plastic melting on your first run.
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