So I’ve been away for a while. My new project is trying to come up with a better grinder. This one is a modified leaf mulcher. I rebuilt the head to take rebar teeth and built a steel plate for them to pass through. It’s still too fast and needs a speed control device of some sort. The nice thing is it has a shut down and brake built into it. Wyatt and I tried it on hard wood charcoal this evening. Worked like a charm. Next step DUST CONTROL as the video shows well.
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So this is still very preliminary but the grind size looks very good. As an added feature it provides its own blower that is blowing the dust out of the ground charcoal. I just need to incorporate it into a sieve ramp and a cowling of some sort and shoot it in a direction I like. Its an impressive amount of dust that is for sure. This batch of charcoal is at least 25 percent ash though…
Cheers, David
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Is this a chipper? Did you modify it?
yes its a small chipper, shredder that I modified.
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Humm, definitely fast, but as you know, the faster you go the more dust you make. Also 25% ash is very high and 100% of that will be given off as dust. You could sift it out first. Then there is all that charcoal dust that is blowing away which could be used as biochar. As you suggest, slowing the motor down will really help. My grinder runs at about 100 rpm. The crushed charcoal tumbles down a sloped screen where the dust falls out and into a bucket. The side boards on the screen reduce the amount of air movement that can blow the dust around. Good start, you will only make it better.
Gary in PA
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thanks Gary. My buddy Wyatt is building a slower one much like yours. We will have to run them side by side. We sifted out the ash from the next batch and the dust seemed to be all charcoal. If I can chanel it with a cowling Ill try to get it to deposit and Ill use it in the garden.
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It seems to me that the way to capture that dust for re-use would be a vacuum cleaner. Now we all know that fine dust will plug up a vacuum’s filter in no time. I have an old Rainbow vacuum that would be Ideal. it draws the dust through water as the filter, so never plugs. Your dust of course becomes mud, but I guess that doesn’t matter if you are spreading it on the garden anyway. Maybe you could use your manure tea or whatever inoculant as the filtering fluid and kill two birds with one stone.
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i was thinking a furnace blower and a mister…
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You might try an used sweat shirt, or a pillow case over your yellow tub, make a tear in the fabric as necessary to fit your output chute…If your going for inexpensive, easily renewable, & no additional energy put into the processing, to knock dust down.
I use ‘used fitted bed sheets’ [generally 50 cents or less at garage sale] that will somewhat fit my rear-bagger leaf trailer, knocks the dust into the wagon, easily captures 70% of my dust problem.
I know it might sound really cheap, but I get those clothes hangers available at the second hand store [free], and they open up to hold skirts or slacks, they look like a wire/wooden big clip, they ‘lever over’ to lock, those will hold various fabrics to the rim of the yellow tub, quick to use.
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Interesting. I was thinking geotextile cloth. It’s porous and I have a lot of it around. Used Sheets would certainly be cheaper.
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David, great Idea for a grinder. Try on the A/C in put a heavy duty light dimmer switch and slow the motor down.
I also put a shower curtain around my Grinder/Trommel Classifier to control the dust . Put some straw down and weighed down the curtain on the straw, forcing the dust though the straw filter. Good to use the filter mask though. We don’t want to get Black lungs.
Have Charcoal Will Travel.
Bob
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Hi David , coincidence posting pictures on your wood chipper the very morning i was outside dragging my little chipper up onto its new home , i have a few of your type of wood chippers too , but unless you can drive the motor with a Variac to lower the speed i think maybe swapping out the ac motor with a dc motor would work better for you , at the moment i am using an old petrol B&S chipper shredder and taken the pully and belt off and bolted a wheel chair motor and gearbox onto the back of it , now it has low speed and lots of torque too , its running about 100 rpm and i get very little flying dust unless i have lots of softwood in my mix and that seems to float up , i have had a few very large mountain ash gum tree;s felled on my property and i am cutting each and every branch with leaves on by hand and burning them one at a time in a cone and getting lots of lovely ash for the garden and charcoal for my engine’s
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Centrifugal blowers and cyclone filters have been used for many years to separate dust and stuff from grains exiting hammer mills. The cyclone would need to be configured for dust and air flow rate.
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If l may add my 2c, the easyest way of them all is seal the whole thing. Thats what l did. Take a plastic bag, tighten it around the grinder outlet with a elastic rope, or eaven better, a bicycle inner tire (JOs “ductape” 
) and do the same on your grinded char bin. Grind untill your binis full, then wait a few minutes for the dust to settle and you havent got any dust no more!
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I like it!! I would do it over the garden I think. I know it’s insanely dusty right now but it grinds beautifully.
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I produced the raw charcoal last year by shoveling excess coals out of my outdoor stove. I will have to have some sort of sifter to remove the ash this year. I was also thinking about using a fork instead of a shovel to get only coals.
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Perhaps a plastic scoop shovel drilled full of holes?
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That would be ok for the cooled charcoal Bruce but I am going to try to harvest hot charcoal out of the furnace without bringing out much ash. Something built in the shape of a scoop shovel but made out of steel rods would fit the bill. A straw fork would probably work but I think they are fairly wide. The other choice is some sort of sifting system when the cooled charcoal is transfered form the cooling pail into the steel barrel. I was dumping hot charcoal into the barrel but under some conditions it keeps heating and converting to ash so I now use a two stage storage process.
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Ohhh, perhaps hardware cloth screen fastened to the straw fork or an aluminum scoop shovel with slots or holes.
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Any of those would probably work, I will more than likely use whatever is fastest and easiest to fabricate on a last minute schedule.
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