Uses for sawdust #1: I just got a thing from the tool crib on the uses for sawdust

This is an interesting post. Thanks for the link, Obi.

-- With God's help all things are possible- even woodworking. Woodworking is not just a hobby, it is an (expletive deleted) expensive hobby.

Very interesting. They talk about a paint can in the example but don’t say alot about how much of an area it heats. It looks like it might worth investigating further. Thanks for the link.

-- When you give someone a chance it may well be their last.

Here is the entire article from Tool Crib

-- http://ye-olde-cabinet-shoppe.com/

good post on this subject. the amount of sawdust that I create, I would have to use a 20 gallon can to keep up with it.

-- Tim -- http://tmuli.com

Thanks for the links Obi. I have just drilled a couple of holes in the bottom of a 2 gallon paint drum and used a 2” plastic pipe.

The sawdust is from my pile created by cutting some trees into planks a few weeks ago, so not 100% dry yet, but it works. Getting it started was a small problem – when inserting the paper the sides wanted to collapse. But it was just started and burning well with no discernible smoke, but definitely some fumes.

I do not know if I would trust it inside the workshop overnight, but it certainly would be useful to keep the frost out of the greenhouse in the early spring.

Any way going to leave it to burn overnight and see what it is like in the morning – I’ll let you all know tomorrow.

-- Tony - All things are possible, just some things are more difficult than others! - SKYPE: Heron2005 (http://www.poydatjatuolit.fi)

I think they were using a 5 gallon can, Tony.

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It’s been 2 1/2 hours and the 2” diameter hole is now 4” but still burning and giving heat.

I do not have a 5 gallon drum at the moment, but if this works on a small scale, then I might invest some more efforts into this.

-- Tony - All things are possible, just some things are more difficult than others! - SKYPE: Heron2005 (http://www.poydatjatuolit.fi)

so the hole in the bottom of the can is getting bigger. Nice to get actual tests results. maybe we can come up with modifications as we go along.

-- http://ye-olde-cabinet-shoppe.com/

I was just thinking about the hole in the bottom. Maybe if you mixed up a little concrete and with the pipe in the hole pour the concrete around the pipe so not to burn the metal bottom of the can. After the concrete sets up, remove the pipe and let the concrete finish hardening overnight.

-- http://ye-olde-cabinet-shoppe.com/

This is getting good. Thanks, Tony for the experiment. Now I’m really curious how much heat is given off, how much area could be warmed with a 2 gallon furnace? Could the fumes be the result of the sawdust not being fully dry?

Obi, I was wondering the same thing about the can; how long would it last before it burned out? Unfortunately, I don’t need heat this time of year, so I can’t really give it a try for some months.

-- When you give someone a chance it may well be their last.

Well appearantly Tony burned the bottom of the can from the 2” hole to a 4” hole. If you put 2” of concrete in the bottom, I’d bet money that it wouldn’t burn out at all.

Another thing is I buy my lacquer and thinner in a 5 gallon can, so it seems to me that it might heat a larger area for possibly longer. I don’t know, because this wasn’t my design, I just happened accross it from the folks at Toolcrib.

-- http://ye-olde-cabinet-shoppe.com/

I didn’t realize that was the hole in the can, I thought it was the hole in the sawdust. That makes a big difference.

-- When you give someone a chance it may well be their last.

I’m checking the article again to make sure we don’t burn down the house.

-- http://ye-olde-cabinet-shoppe.com/

When the can is full, completely cover the top of the sawdust with a thin, even layer of sand or ashes. Then twist the pipe back and forth and carefully pull it out of the packed fuel. You’ll have a neat hole—which will act as a chimney—right through the mass.

This must be their idea of a lid to keep the fumes from rising right in your breathing area. Saving the lid of the can might also be another way of “keeping a lid on it”.

-- http://ye-olde-cabinet-shoppe.com/

Here are a few photos taken 3 hours after lighting

Flash Photograph

Hand held No Flash

Hand held No Flash

-- Tony - All things are possible, just some things are more difficult than others! - SKYPE: Heron2005 (http://www.poydatjatuolit.fi)

The bottom of the can is not burned through – the hole made in the sawdust has increased from 2” to 4” – the can is still intact

-- Tony - All things are possible, just some things are more difficult than others! - SKYPE: Heron2005 (http://www.poydatjatuolit.fi)

That’s good to know. Thanks.

-- When you give someone a chance it may well be their last.

so… the test was a success. Glad to hear it. Now that’s it’s june and heat isn’t as big an issue, we can save our sawdust for next winter. Also the idea will work for when we go camping, or in our Yurt (if we have a Yurt, that is)

-- http://ye-olde-cabinet-shoppe.com/

Oh, and you might want to think about that red plastic handle.

-- http://ye-olde-cabinet-shoppe.com/

So, Tony, how big is the area you’re trying to heat? How warm did it get? It’s up to you, Buddy, to give us the low-down and rate this on a scale of 1-10.

-- http://ye-olde-cabinet-shoppe.com/

If your using in your shop you might want to get a carbon monoxide detector. But looks like a interesting idea.

-- We must guard our enthusiasm as we would our life - James Krenov

I am going to follow this up in the morning – but its been over 4 hours burning now and still going – as an initial experiment it looks quite promising. 1 am here time for bed

-- Tony - All things are possible, just some things are more difficult than others! - SKYPE: Heron2005 (http://www.poydatjatuolit.fi)

This is very interesting.

-- Andy Stark

I’d be a bit concerned about carbon monoxide from a slow smouldering fire…if you had enough fresh air to keep it safe to breath would you have any heat retention? Are you getting any fumes from the residue from the can’s contents? Yeah th fire may work but is it worth the risk of CO poisoning to save some coin? By time you realize you are affected by the CO you could be in a situation where you are unable to react and get yourself safely away…nevermind any unsuspecting family members who may not be aware of the CO experiment happening. Tony, I hope your shop is not attached to your home in such a way that the CO (denser than air so it will flow along the ground) could flow into your sleeping quarters…. Call me paranoid but can somebody close call Tony and make sure he is okay?

-- ....next big purchase is wood for the next project, Mark

I think a thicker plate steel in the bottom maybe better than concrete, as concrete explodes when heated to a high temp.
Anyway just a thought, I like the idea maybe keep the skeeters away …lol
Jim

-- A duck that brags on his own pond, soon swims alone.

I didn’t know that about concrete.

-- http://ye-olde-cabinet-shoppe.com/

Don’t think anyone is close to Tony, he is in Finland. : ^ ).

-- We must guard our enthusiasm as we would our life - James Krenov

Hello All

Thanks for the concern over the CO emission, but the experiment was performed outside for this reason, also the thought of a unattended, unguarded flame in the workshop frightens me.

The fire was lit last night at 9PM, at 2AM it was still burning well, generating a lot of heat. At 7 AM this morning, 99% of the saw dust had been burned away and the ashes were still hot.

This little fire could certainly cook a meal with no problems, however as for heating my 130 cubic meters (4590 cu ft) not much chance, especially in the depths of winter. I might try this fire in my finishing room, that is only 44 cu m (1553 cu ft) and most of the time I only need to keep it above freezing to stop damage to my finishing stock.

As the fire stands at the moment, it cannot be used safely inside. However, the next stage of the experiment must be to place a similar container on top of the fire container and to add a chimney, as suggested in the original article. The upper container will get hot and dissipate the heat into the environment.

But adding a lid and chimney will alter the air flow from the bade, at the present time, the wood chip ash falls o the bottom of the container and blocks the ventilation holes, therefore the fire draws the fresh air over the rim and down into the burning vortex, with the lid chimney attached it cannot do this, so I think that the number and size of holes in the base has to be increased to compensate.

The amount of heat produces was reasonable, the burn rate increased, as did the heat output in proportion to the increase in size of the vortex.

Oh well back to the grind stone!

PS, the red plasitic handle is still intact.

-- Tony - All things are possible, just some things are more difficult than others! - SKYPE: Heron2005 (http://www.poydatjatuolit.fi)

Thanks for trying this out Tony. The numbers on the size of your shop are useful for judging how something like this might work in my shop which is about 3200 cf.

-- When you give someone a chance it may well be their last.

Russel, is that cubic feet or square feet?

-- http://ye-olde-cabinet-shoppe.com/

Tony,
If you put an oversized lid with an overhanging lip, that didnt sit right on top but the overhanging lip around the edge could draw in fresh air and keep the smoke and fumes going upward.

I guess what I mean to say is if you put the ventilation around the top of the can, it could draw air in through the top .

-- http://ye-olde-cabinet-shoppe.com/

What about increasing the height of the can, to get ride of more ash? What was the height of the can from the ground?

-- Andy Stark

The height of the can was not an issue – as long as you can get a good airflow underneath (about 4”). The holes I drilled in the can were 5mm dia about 15 of them – these are too small to allow the ash to fall freely out of the bottom. You CANNOT shake the container, otherwise the sawdust will collapse.

I think if I were to say cut a 3” diameter hole and cover the hole with some 1/2” mesh, the ash may fall through freely, but I think there will be too much convection of the air, causing the fire to burn much more rapidly.

Trial and error, trial and error, error, error, error!!

-- Tony - All things are possible, just some things are more difficult than others! - SKYPE: Heron2005 (http://www.poydatjatuolit.fi)

NM. I alslo try to compost some of the sawdust, but there is only so much you can mix with grass cuttings, otherwise it becomes too acid.

Some of the larger chips I use as a mulch, mixed with chopped leaves – and the good quality chips, Oak, Birch beech I use for smoking fish and meat. But the chips from ripping trees with the chainsaw, is so fine and mixed with chain oil, it is not much good for the garden, this is why Obi’s post on this subject gave me such enthusiasm to try this – I may get some free heat, get rid of the garbage chips, and get some good quality fine ash for spreading on the lawn (WIN, WIN, WIN)

-- Tony - All things are possible, just some things are more difficult than others! - SKYPE: Heron2005 (http://www.poydatjatuolit.fi)

Obi, you point is noted on the overhang, I had not thought of that, but I will keep it in mind.

I am going to have to stop all fires at the moment, as we have a severe forest fire risk at the moment – No rain for 6 weeks and Blue Sykes and temperatures well into the 80’s

-- Tony - All things are possible, just some things are more difficult than others! - SKYPE: Heron2005 (http://www.poydatjatuolit.fi)

Obi, that’s cubic feet. I have a detached two car garage that the car has never seen the inside of.

I’m wondering if the can were set in a type of brick “oven” with an open top an front how the heat distribution might be affected. I know I’d feel safer if the whole burning thing were somehow enclosed.

-- When you give someone a chance it may well be their last.

Tony, glad to hear you are okay. I should have figured a Lumberjock would be smart enough to not risk CO poisoning.

It is an interesting experiment, I’ve been mulching my sawdust so far. I have been listening to a radio program where they talk about terra praeta “black soil” (http://podcast.cbc.ca/mp3/quirks_20080531_6042.mp3) where sawdust/wood are charcoalized and buried, significantly improving the nutritional quality of the soil. I think I’m going to try this.

-- ....next big purchase is wood for the next project, Mark

this is very interesting… i guess that i am the next in line for testing this, as it is winter now in nz…. and i have lots and lots of saw dust.
now, if i only had a large metal paint can….

i can use this for heating the outdoors. we get cold wind in late afternoon during the summer.

-- The woods are lovely, dark and deep, but I have promises to keep...

Oh! I just had the most brilliant idea! logburners are probably the most common way of heating here. i can put a can like this in the logburner! it would be safe and will heat the firesbox!

-- The woods are lovely, dark and deep, but I have promises to keep...

made a little experiment with 1.5L tin. works very well, produce lots of heat, but i found that it is too dangerous to use in the garage as some of the heavier sawdust is lifted by the strong column of hot air produced by the stove and you get lots of “sparkling bits” flying in the air. not sure they survive to be hot enough to ignite anything on landing, but not going to check this :-).

I might try it with a fine wire net on top (i think the best would be net from half sphere sieve. this will serve two purposes, one is stopping all the sparks and the other is distributing the heat better as radiation. currently, all the heat goes upward.

Tried my brilliand idea of putting this in the logburner. it works well, but the tin is not in the right dimentions (too close to the top of the logburner). I didn’t have the metal legs, so i just put it on two of relatively wet logs. after a while, it ignited the logs and the experiment was pretty much over….

I’ll get back to this later this week. I was thinking of making “disposable” packages for the sawdust instead of tin (thereby making the handling simpler). I will try to use several sheets of newspaper as the “walls” and some cardboard as the bottom. i count on the fact that newspapers, even after they burn, still work as effective oxygen barrier. will keep (and the fireman) posted.

-- The woods are lovely, dark and deep, but I have promises to keep...

Oh, another thing – this fire seems to have two modes. one is amber smoldering (I think this is what Tony got) and the other is high flow, high heat column of flame, which burns much faster and produces more hear and less fumes. to switch from the low mode to the high mode, put a small flame under the can (several matches or bit of newspaper of a chip of zip ignition block – be careful when you do that – don’t use your hand to put it there).

-- The woods are lovely, dark and deep, but I have promises to keep...

Moshel,
Try using bricks as legs.

I once worked for a cabinet maker in Oregon that had a 2-stage wood burner in his shop. The top barrel got hot also, serving as a double heater/ spark catcher, keeping the sparks from going anywhere.

-- http://ye-olde-cabinet-shoppe.com/