Glog briquette failure!

[Julian]

Inspired by this web page ... http://woodgears.ca/reader/alois/press.html  I had a play making this this evening ...

Lump of 32mm solvent weld waste pipe, a lump of lumber turned to fit on the lathe and a suitable bit of MDF.




Loaded with quite a dry mix of glycerine and sawdust and compressed in the vice.  As I suspected, the glycerine squeezes out ... doh!




The result comes out as quite a respectable briquette, but quite quickly decompresses and breaks up.




I was very impressed with the pressure the waste pipe took as the vice was wound up quite tight, but yet another heroic failure to add to "Julian's list of heroic failures", but I guess you've got to try these things!

[julianf]

Why is that a failure?  Cause it breaks up?

Dont whack it about then! : )

As a side note, i reckon your sawdust looks a bit corse, and your mix a bit wet?

[Julian]

It's a failure because it reverts to a loose mix of sawdust and and not very much glycerine, most of it having been squeezed out in the manufacturing process (or should that be un-manufacturing process!) and it breaks up of it's own accord.

Sawdust is a mix of fine and shavings.  I've tried very fine sawdust and I can see little difference between the two.  The mix I tried is about the same as I burn or a little dryer.

[greasemonkey]

Its got potential.
So you may need something to collect the leaked out glyc.

I reckon the bloke on that tools website started barking up the wrong tree. Far be it from me to say, but with the amount of technology and effort he has put in, I think he would have been better of looking at making a single log at a time.

Dump a measured amount of mixed dust and glyc into a mould, and compress from above, so the ram is going vertical.

Just thinking out loud really.
I wouldn't bother with a hydraulic ram. I'd be looking at something like an old steam hammer. Lift a big weight up the a certain height, the let it go. Far more efficient.

[Julian]

Making sawdust briquettes works because lignin or I guess, resin helps bind the dust together.

Once the dust is soaked in glycerine, it recon it prevents the lignin from doing it's job.  I did try dry saw dust on it's own, but my dust is hard wood with a very low resin content and it probably needed more pressure than the plastic pipe could manage.

I recon my idea of an oversized Rizla machine may be the best bet for glogs.

[whatarascal]

Fine sawdust + glyc wrapped in newspaper "like fish,n chips" is all you need to do.
Mix in a bucket,dustbin,cement mixer,whatever.Fast and simple.
K.I.S.S

[julianf]

Julian,

Ive read that veg oil is somtimes used as a binding agent when the lignin is  not sufficient.

That aside -

When i make glogs, i pack them into carpet tube, which isnt much smaller dia than soil pipe.

When ive considered using a ram, ive thought about packing them into these.   Ive also thought about some way to fill the whole tube, storing it as a whole length, and then chopping them when needed. 

Using the whole length would lessen the packing time, and stop excess falling from the ends when stored.  But then the same loss may occurr when sawing before use...

Anyhow, i just thought id mention this, and see if it triggered any more ideas for you!

One final one -

I dont much like this plan, but some sort of auto wrapping device, using clingfilm would make the units much more handle'able.

[therecklessengineer]

I dont much like this plan, but some sort of auto wrapping device, using clingfilm would make the units much more handle'able.

Something like an oversized sausage machine?

[Keef]

Or line the tube with a freezer type bag before filling?

[knighty]

what about big heat shrink ?

you could heat it a bit to help squash it a bit extra at the end ?


no idea on cost... or fumes/smell when you burn it tho...

[Julian]

Interesting, I'll try a bit of veg oil mixed with the sawdust, but I don't think the vice and plastic tube are creating enough compression.  I have seen briquette makers with heated barrels and the briquettes coming out charred.

I currently use carpet tubes and fill them by hand and it's a right PITA and messy too.  Some glogs leak glycerine in storage and I think that problem will be more prevalent over the summer with the warmer weather.

They also need to be sealed or wrapped for carrying through the house (I currently wrap them in newspaper for trans dwelling journeys) so some of the ideas above are headding in the right direction.

[Julian]

Quite like the sausage machine idea, but for filling carpet cores.

You'd have to make sure the end was securely closed and that you had some kind of tension control over the feed of the tube.  This could then be cut into lengths, but you'd still have the problem of the sawdust uncompressing once cut.

[nigelb]

Do you not just think that you had too much glyc in the mix.

[Julian]

Err, in a word no.

But I've only my own experience on which to draw.  I've tried a dryer mix and to my way of thinking you need a reasonable ratio to get a good flame.

My glogs stay intact throughout their entire burn and evolve gases which usually burn in the secondary air (if I tend the stove regularly).  At the end of the glogs burn I can poke them around and they fall appart , burning more fiercely, just right to get the next glog going.

[nigelb]

Err, in a word no.

But I've only my own experience on which to draw.  I've tried a dryer mix and to my way of thinking you need a reasonable ratio to get a good flame.

My glogs stay intact throughout their entire burn and evolve gases which usually burn in the secondary air (if I tend the stove regularly).  At the end of the glogs burn I can poke them around and they fall appart , burning more fiercely, just right to get the next glog going.

Err...Ok! Just a thought considering the amount of glyc you squezzed out. Sorry....I'm out!