EverythingNice stove build

I've been playing with home made gasifier stoves for a little while now. I'd watch some youtube videos of other people's stoves, find some tin cans, drill some holes and fill it with some biomass that was lying around. The results were never great, they would usually burn for a little while and then go out and give out lots of smoke. Using different quality fuel each time also made it really hard to tell how changes I had made to the stoves affected them.

So I decided to get some proper fuel and make a proper version of the EverythingNice stove from Worldstove (plans are here).

First thing was to find some suitable tins. I needed the two diameters to be within 8-10mm of each other, and the smaller tin to be 8-10mm shorter. After exploring the aisles of the local supermarket for some time, I ended up with a tin of Lindt drinking chocolate (with a nice lid) and a standard baked-beans can. Following the instructions I drilled a series of 12mm holes around the base of the Lindt tin, and then cut a 37mm hole out of the centre of the lid with tinsnips :

Lindt chocolate tin

The inner tin got as many 4mm holes as I could, centred on a line 18mm from the bottom of the tin.

Old baked beans can

 Each tin had a 3mm hole drilled in the bottom at the centre, so a M3 bolt could be used to keep the two tins centred.

Holes drilled for centring tins

Centred using one M3 bolt

Turns out finding wood pellets in Sydney isn't as easy as I thought. There are places that sell them, but they seem to want to sell by the pallet load. I found this product called Oz-Pet Cat & Pet Litter which are just wood pellets, but sold as kitty litter. Got a 10kg bag for ~ $14 from a local pet store.

Fuel pellets masquerading as kitty litter

Now for the fun part. I filled the inner tin up to the "fill line" (18mm from the top) with pellets. I soaked a couple of wood pellets in some metho for about 5 mins. Then I dropped them on top and lit them using my girlfriend's creme brulee torch (sshhh).

Here's what happened:

• Stove lit nicely with a blue flame (due to the alcohol). Began gasifying within around 2 mins
• Burned with a fairly strong orange flame for ~55mins
• Produced virtually no smoke (until the end ...)
• After around 55mins, the flame died down and a little smoke started to be produced
• After the flame went out, it made lots and lots of smoke. I mean lots. I assume this would have gone on for a while, but I poured a bucket of water over it. That stopped it smoking.

In this photo you can see the flame ...

... and in this one you can see the tin. Use your imagination to combine the two.

 After everything had cooled down a bit I had a look at what was left of the wood pellets. On top they were very nicely pyrolised, but as I dug further down it turned out there was a cone-shaped region of unburnt pellets at the bottom. This would have been what was causing all the smoke at the end. Here's what was left:

The aftermath.

Note that the unburnt pellets have swollen up quite a bit from the water, they would have been the same size as the charred ones.

So, all in all, I was quite happy with the stove, especially for a first (proper) attempt. It burnt really well while it was alight, just need to get it to char all the fuel, and to not smoke so much once it's done.