I’d have to measure but maybe 2 inches apart at the most.
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The only way you aren’t getting a hole lit is if it’s blocked.
You only need one hole lit and it will drift over to the other holes.
The most surefire way to determine if you have an air leak is to fill the unit with water, or to blow air into the system and spray soapy water on any of your welds or threads.
Charcoal gas is less energy dense than woodgas because it’s missing the methane.
Also your generator was designed for gasoline, so it can’t utilize the gas as well as it could. If you want to increase your power you could get a spark advance flywheel key to set a permanent spark advance, or you could shave the cylinder head to increase compression.
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Thanks for the quick replies. I figured the flame would migrate anyplace it was getting air but wasn’t sure if that might have been why I wasn’t getting full power compared to the simple fire updraft. The nozzle in the simple fire doesn have larger holes instead of getting smaller towards the back. I looked back in this thread to my last picture of the nozzle and the holes were getting smaller from the slag as well as the last two being drilled smaller.
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Are your jets still pointing up? Might be a good idea to go ahead and point them down.
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They are all getting fired up for sure. But like others have found if the nozzle holes get smaller it will have less flow out them with amount of vaccum the engine can pull running. What happens when you cut back on the intake air being able to enter? You are choaking the engine down. Open the nozzle holes up and see what happens.
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I did buy an extra flywheel key to change the spark advance but haven’t tried that yet. Not ready to shave the head and don’t want to make it unusable on gasoline but figured I could file (grind) the new key a little bit at a time.
The generator never did run on charcoal as good as it does on gasoline but this one isn’t as powerful as it has run using the simple fire when everything was working right.
I’m just using rubber couplers to hook this one up enough to test it. The cooler isn’t hooked up right to cool the gas as much as it should but I still hope to put the cyclone in before (or maybe instead of) the cooler.
I’m probably going to resort to silicone on the cyclone to get it sealed. That metal is pretty thin. I might even skip the cyclone all together and just use the cooler I built. It looks like the straw (grass) is filtering it and not restricting the flow like the felt was and that filter (with the rocks) has a drain for the condensation as long as it doesn’t have as much as it did before I got most of the moisture out of the ashes.
Brian, l still belive the main cause for lack of power is moisture. Not only does it dilute gas, it robs the gasifier of energy that wuld otherwise be used to make burnable gases. A correctly tuned charcoal gasifier can not produce water in the radiator, period. Its just not possible. Key is finding a ballance of just the amount of water in your fuel that the gasifier can digest, no more and no less. This gas then is rich and absolutely dry. Also, once the ideal fuel is found, consistancy is key.
You are doing great so far, keep it up! Victory is close.
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I second what Kristijan is saying.
First step would be to not add any wood to your gasifier, wood just adds moisture.
Second step might be to add a channel up near the lid of the gasifier to collect any moisture in the fuel and collect out into a tank. A monorator hopper. A good way to make a channel would be to find a bicycle rim close in size and splitting it in half. It doesn’t need to be deep, just has to collect dewy moisture and run outside.
Have you noticed any condensation inside the lid when opening it up?
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Hard to keep up with all the replies. Thanks everyone.
Cody, the holes are already facing down.
Bob, that makes sense. I have shut it off with a ball of foil in the nozzle opening and now have a pipe cap to shut it down better. I did notice that blocking it partially changed the engine and making the holes too big would just mean remaking the nozzle and it will likely eventually wear out anyway. I purposely started small so I could keep drilling the holes bigger but hard to tell when to stop.
It did run better than the longer run and the bottom section (where the ashes are) only got a little over the boiling point when I made the charcoal in it and it wasn’t held at that temperature for very long so it probably still has moisture from there. I reused the charcoal from the other run and wasn’t even thinking it was probably pretty wet too. Hopefully it continues to get better with another run or two. It is usable now and easier to load than the simple fire.
Yeah, there has been condensation inside the lid. That was part of the reason for adding the extra ring inside the lid to help keep it from running down the outside of the hopper. I’ll have to see if I have a bicycle rim close enough to the right size. Getting the moisture out of the ashes and not getting too wet of charcoal should fix the problem but I’ll keep the monorator idea in mind if I can’t get the moisture down low enough.
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Back in the 1970s Atom came up with a knock sensor (microphone) based ignition timing system. It advanced the spark automatically, so you really didn’t have to set timing. Nowadays, you can buy retrofit magnetos with all that built into it. I put one on my old 1960s flat head Briggs 3KW generator. It works great. I don’t know @BrianAltEnergy 's generator but I suspect it already has timing advance built into it.
Rindert
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Just wasting some time thinking up possible projects.
Has anyone cast their own hatch covers out of aluminum?
A wooden (or maybe 3D printed) pattern could be made including any fillets and draft angles needed to get it cleanly out of the foundry sand.
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I have worked in the foundry business. They usually make patterns out of RenShape. But for just a few castings I usually use MDF. Do you have a CNC? Also we have a whole thread dedicated to metal casting.
Rindert
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Yes, I have a homemade CNC router. That was part of the thought behind this especially the text.
A lot of the pattern could be made as sections and glued together. Even Styrofoam could be used either as the pattern for sand molding or as a one time use lost foam pattern.
My main thought was that the cover wouldn’t need any welding and could likely have a pocket or groove cast in to put the gasket.
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I would change the lid to have a central post on top, where you could attach a coil spring from maybe an overhead valve, and a bar with a hinge on one end and a latch on the other.
Something like what Gary has on his Ranger
Edit: note how the bar has a hole running through, this allows the lid to jump up in a puff event.
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Thanks Cody, I’m not sure how I missed that video. Looks simple enough if I can find the right spring.
That’s one of the problems with my design. The lid isn’t sealing good enough especially if I’m blowing air into the nozzle to get it burning good or for flaring.
Today I did hook it back up after drilling the holes out bigger. The nozzle is getting thinner so it isn’t going to last a long time but that helped a lot. I was able to refill my air compressor tank all the way without loading the generator down much. I tried the miter saw and same thing, it ran fine.
I was going to pump some power into my 12 volt battery but the sun is hitting the solar panels and that battery is charged.
Only ran the generator about 15 or 20 minutes using the same charcoal I had in it last run. The only change was the holes in the nozzle enlarged and more of the moisture had been removed from the last run. I still got about 2 more ounces of water out of it in this short run but it’s running as good as the simple fire now and has larger charcoal and there’s still a piece of two of raw wood that hadn’t fully converted.
The weather got a lot colder and I’ve been using the house furnace and getting some charcoal out of it about every time I reload it with wood. There isn’t a lot yet but probably an hours worth of charcoal from it.
There’s a little bit of ashes mixed in and some of the pieces need broken up smaller but doesn’t seem as wasteful as just burning the wood in a barrel to get the charcoal. Once I take my good barrel near the furnace room and start heating continuously I could see that keeping enough charcoal produced to run my generator and I hope to stockpile the charcoal over the winter.
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I forgot about the other change but I don’t think that had anything to do with the generator running better.
I got a mesh laundry bag to put my grass/straw filter material. The bag wasn’t quite big enough so I blocked the space with more felt but that should make cleaning or replacing the filter material easy.
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Ever think about using the heat from a tlud to heat the house, while making charcoal? Very cool Aussie Bio retort - #7 by d100f Too many ideas.
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With your CNC router, you can probably just cut aluminum directly. most ones designed for wood, you can also do soft non-ferrous materials. So then, you just need to cast a block. It skips making the pattern and trying to cast it perfectly, and dealing with shrinkage, etc.
If you are dead set on making a pattern, another way, would be to do spin forming. you make the pattern, and take a sheet metal, and press it against the form while it spins. It is an art all by itself, but then you could use stainless or another material.
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That TLUD looks nice but I couldn’t put something like that in the house. Might be perfect for use in a workshop or greenhouse though. I couldn’t find any actual drawings or plans for that device but the comments made it sound like the hopper is just a stove pipe:
The fuel container is made out of stove pipe. The primary air is forced down one of the vertical square tubing supports that holds the heat exchanger. The heat exchanger can be removed and replaced with a cooktop. It only takes between 2 and 3 watts to run the primary air fan which is a 12 volt computer fan with a speed control added to the circuit.
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When the pyrolysis front burns out the charcoal starts burning and produces more heat that trips the thermostat that shuts the fans off.
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I know this is an older video but i’m just now seeing it. To answer your question oxygen (air) enters through the bottom of the fuel can and migrates up through the fuel until it reaches the fire. The fire depletes the o2 and leaves the char behind, migrating down the can as it burns. The spent gasses go up the fuel can. At the top where more O2 is introduced the hot gasses reignite and go up the stack. The key to this is stopping the the burn when it gets to the bottom of the can. Otherwise the char that is left behind will burn from the bottom up leaving nothing but ash behind. If all you are after is heat no problem if you want the char you have to stop the burn. Hope this helps.
The top looks similar to something sold as “Magic Heat” but probably bigger.
Mine isn’t rigid enough and it would need to be run very slow to cut. Even hardwood I can’t go real deep or real fast.
Back in high school I did a tiny bit of metal spinning but haven’t tried to set up any way to do that myself. That’s a good idea though. My sawblade cover is working but I added a piece of felt (in addition to the stove rope) to help it seal better. So far that hasn’t gotten too hot.
Doing a little more studying, I still think my main problem was the moisture in the ashes but the raw wood even mixed with the charcoal was probably creating a lot of the moisture too. The last run had very little raw wood and it run pretty good.
I don’t regret trying the raw wood and it looks like I could get away with at least some less than perfect CHARCOAL but I don’t want to add a monorator hopper or all the heat exchangers that would be needed to use raw wood. Not on this one anyway.
I had already used some of the charcoal salvaged from the house furnace but this was what I was able to collect from a couple days without really trying. That should be enough for over an hour run time for the generator. The colder it gets here, the more charcoal I could potentially collect and purposely feeding smaller chunks of wood would speed up converting it into coals.
I’m not happy with how my cyclone is turning out so I think I’ll stick with the radiator I made and use the filter to collect any moisture like I have been doing. This down draft gasifier is starting to work about as good as the simple fire but holds more fuel and shouldn’t need as perfect of charcoal. It probably won’t hurt if a brand or even a tiny bit of raw wood slips in but the rocket fuel idea looks like it adds too much moisture if not some tar.
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