Turning woodworking dust and chips into burnable "logs"

Frank Pellow

Member
Messages
2,332
Location
Toronto, Ontario, CANADA
This week, I successfully burned a pressed log that I made solely out of dust and chips collected in the woodworking shed. For a long time, I have been crerating more dust and chips than I can easily dispose of. The city doesn’t want them either in garbage or in garden recycling material. I tried then as mulch, but the material tends to clump up and, so, later it becomes hard to work into the soil. It is possible to incorporate a bit of the dust and chips into my own compost bin where it is well mixed with other material. It is also possible to burn by throwing handfuls onto a fire in the stove my workshed, but that is messy. As a result of all this, I have now accumulated 5 very large paper bags of dust and chips. Here is a photo of two of the bags:

Bags of woodworking dust and chips -small.JPG

What to do? The clumping in the garden gave me an idea. I drilled some holes in a large can, made a removable wooden top, wet some dust and chips, pressed them into the can, then let the mixture dry for a couple of days. I thought that the clump would simply drop out of the inverted can, but that didn’t work. I had to take off the bottom and cut the can down the side in order to remove the log”.

Compressing woodworking dust and chips in can -1 -small.JPG Compressing woodworking dust and chips in can -2 -small.JPG

After drying the log for another five days, I put some kindling under it in the stove, lit the kindling, and obtained a good fire. Here is one photo taken about five minutes after lighting the fire and another taken twenty minutes later:

Burning compressed log -1 -small.JPG Burning compressed log -2 -small.JPG

By the way, the dried log held together fairly well before I burned it, but it certainly would have come apart if not handled gently.
 
Of course, I don’t want to cut a can apart for every log that I create so, this week, I built a form that can be used to make a large rectangular “log” block:

Pressed block of woodworking dust and chips -1 -small.JPG

The form is designed to be temporarily held together with clamps. In the first picture below, the dust-chip-water mixture is being pressed into the form and in the second picture the lid has been hammered down pushing out as much water as possible:

Pressed block of woodworking dust and chips -2 -small.JPG Pressed block of woodworking dust and chips -3 -small.JPG

After a couple of days, the form was removed:

Pressed block of woodworking dust and chips -4 -small.JPG Pressed block of woodworking dust and chips -5 -small.JPG

There is a small crack about two thirds of the way from the left side of the block, but I don’t expect this to be a problem.

The next time I make a block, I will mix in a little plaster of Paris, and see if that improves the solidity
 
Frank, how about a 6" piece of HD PVC pipe? Cap on one end, NOT the PVC ones as they are hard to remove, but a wooden one and then a small hydraulic jack? Got to be careful, as you would be making a lot of pressure.

I think you should just buy your milk in the old style paper cartons, then pack the sawdust into the carton, they would lite easy too! :D
 
Frank, how about a 6" piece of HD PVC pipe? Cap on one end, NOT the PVC ones as they are hard to remove, but a wooden one and then a small hydraulic jack? Got to be careful, as you would be making a lot of pressure.

I think you should just buy your milk in the old style paper cartons, then pack the sawdust into the carton, they would lite easy too! :D

Stuart, I like your second suggestion and will give it a try. The olny problem I see is that milk is more expensive in those containers.
 
Ive noticed on several occasions when I put out bags full of only sawdust, my trash collectors, one of them put the bags into the cab of the truck.
I figured he must be using it for either his garden or some slippery and wet work area.
I never asked him. Im happy they just haul it away and thats that.
 
Sounds like a great idea,:thumb:

I was just thinking that a piece of PVC pipe would do a great job as the brick probably hangs up on the ridges of the can.

Once again, back when I could do it, I used to take the dust and shavings out to my daughters property and scatter into the woods undergrowth. Also in the fall we would pack lifted flower bulbs in damp sawdust tucked safely in a dark corner of the basement. Also a neighbor of my daughters used to take it to scatter about in the mud around his barn and feedlot.

The the dust/shavings log is a good idea if you can figure a quick and easy method of compressing. I believe those fire starters are simply wax and compressed dust. Keep trying to find a way to recycle dust and shavings as we all have a common problem.
 
I have been asked about the amount of water that I used in the mixture.

The rectangular block is approximately 10cm x 10cm x 40cm and I used about 2 litres of water.
 
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Although I haven't tried it, I have dreamed about the PVC pipe bit, and the shavings mixed with a small amount of flour. In old days, ordinary baking flour and water was used for paste (even as wallpaper paste), and when dry, flour burns. Therefore my untested plan included using flour in the water to make a better binder for the shavings in the log.
 
Well well well how about a chunk of well casing or steel pipe, with weep holes all around with a lid held in place much like a paint pot. Welded into a frame work with a chunk of round plate to come up from the bottom & a hydrolic jack to press the water out.
 
Charlie mentioned my idea, Charlie when i was a young boy making kites we would use newspaper and flour to make em. Did not have the fancy stores to buy any fancy materials or pre made kites. Flour and water was a go to glue even for school book projects where we cut out and pasted pictures in our excercise books. Was not very nice though.:rofl:

Could do just the trick in this case. Way to Frank i think this idea has loads of merit. I dont have a woodstove but it would be cool to make up bricks to take camping.;)

Fortunately for me i am a few Km from a garden waste recycling center so i get to take my bags of sawdust there and they blend it with the compost mix of old trees and garden waste. Free dumping for me.:thumb:
 
I made a second block, this time with two differences.

First, I clamped rather than hammered the lid:

Pressed block of woodworking dust and chips -6.JPG

After 6 hours, I increased the pressure and moved the lid down about 1 centimetre then, after another 6 hours, I did the same thing. Then I left it for another 12 hours before taking the form apart.

The other change was to add 30 millilitres of plaster of Paris to the water.

The resulting block seems to be a little more solid but I won't really know for another few days when it fully dries out.

The first block has now dried to the point that it is burnable. It wieghs in at exactly 1 kilo.
 
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How about a plain old 5 gallon pail. The sloped sides would allow it to slide out easily. :dunno: Fill it about half way full to get a log thats just about the right size to fit in the fireplace.
 
Great stuff Frank. I was wondering about clamping the mixture to improve integrity (at least long enough to get it into the stove). Very good reuse of our waste material.
 
Len and Kevin on the Canadian Woodworking forum asked a couple of questions that I will share with you here at Family Woodworking.

Les: How long will one of these blocks burn for? as it seems like a lot of work for such a small reward. Is there any concern for the chimney , burning the ingredients that are added to the sawdust?

Kevin: I'll reiterate Les' remark about "what are you coating your chiminey walls with". Frank Pellow, the OP mentioned he is using sawdust from real wood only. I would strongly suspect that an amount of sawdust from cutting ply's and MDF is a definite no-no for this application. Chimney fires happen, I know.

My response to these questions is: The small round log that I made first burned for about an hour. The block that I made next is about twice as big as the log and my guess is that it will burn for 15 to 30 minutes longer. The block is now dry enough to burn but the weather here in Toronto has turned warm again and I am waiting for it to get cold enough for a fire in the workshed stove. Then I will know for sure how long a block will burn.

Les and Kevin, I make the blocks with the dust and chips from my Oneida Dust Extractor and that I almost all pure wood. I don't use a lot of plywood and I use almost no MDF. When I do use plywood, most of the cuts are made with my Festool track saw and that goes into the bag in the conected Festool Vac (which gets dumped into the garbage).

Kevin, I know about chimney fires all too well having been raised in a remote comminity North Ontario town where chimney fires were frequent and where my dad was a volunteer fireman.
 
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What about using milk to bind your mix? The other thing that comes to mind is a coagulant like Jell-O powder. Boil it up, do a thick mix, pour it it, stir it up, then compact it under pressure somehow. A hydraulic press comes to mind, but kinda tedious....


the other would be to use paraffin wax as a binder. I think that is what is used in the synthetic logs you get at the store.

I've made "logs" of paraffin wax and sawdust for getting a fire started when I go camping. Just melted the wax on a pot on the stove, and mixed in the sawdust, then poured/packed it into a milk carton with the top cut off. Works pretty good, I've since turned to bringing a torch, much easier. lol
 
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