MYO gasifier twig stove instructions (large file)

[craigprice]

Thought I’d off some learnings and insights from my testing and experiences - plus a full description of my proven gassifier stove design - I used to make these for others and give them away - it is based off YT, my bushbuddy, solo, and suluk stoves and lots of trial and testing during lock downs in Melbourne.

Apologies this is a long post as a result.

The objective – using materials that are readily available and cheap in Australia, make a simple double walled wood stove, that gassifies so burns smokeless with eucalyptus sticks, sized to fit inside my 1971 800ml aluminium billy; using only basic tools that I already have.

Note: Please don’t use wood stoves in high fire risk areas or on fire ban days

Materials:
• Stove –
o outer = net 800g size can; eg. Coles Diced Italian Tomatoes can or equivalent,
o inner firebox = net 432/425g size can; eg. Dole Pineapple Slices or Cokes Beetroot can
• Pot stand – galvanised or stainless steel 1cm bird mesh – stores in bottom of stove for carrying - or alternatively DIY cross bars or stand from another stove if you have one (about 3cm/1¼ “ height )
• Cost – stove $5, or zero if you are already using the contents for cooking and it would otherwise end up in landfill


Total weight 100-125 g depending on cans (my lightest was 95g)
Outer can diameter 315/16” height 3¼”
Firebox diameter 3¼” height 4 ½”
Pot stand 20g in galv mesh (10g in light stainless steel mesh, 15g as Ti cross pieces)

Manufacturing Comments
You can use other cans – cans are largely standardised in size This size fits inside my trusty old 1971 aluminium 900ml billy. Outer can height should ideally be larger than diameter for optimal air flow and gassifying
It is very important to try to get a good seal in the top between inner and outer cans as this is key to forcing heated gases back into the firebox through the top holes for the gassifier effect
You want the largest can possible for the inner firebox, larger is better (as it holds more fuel) as long as there is still an air gap to the outer wall and importantly the bottom of the firebox needs to be above the holes in the bottom of the outer can to for best gassifying action
The size holes are not precise and just what Ive found from testing different sizes works well – they are also close to those used in other gassifying stoves
If you have them, a bench drill press and step drill bit enable a more professional finish when drilling thin walled cans, and really speed up the process


Notes on Use
Not for high fire risk days/areas (duh!)
Do at least two complete burns before using for cooking to burn off liners and tin coating
The stove is designed for boiling water or cooking in a billy
Use a pot stand of about 1¼” height to avoid dampening the flame, and a windscreen
The gassifier stoves are designed to be loaded with fuel, set and burned in one shot, lit at the top and burn top down. If you have to add more fuel in it will smoke until you reestablish a good burn in the top of the firebox.

Carry the stove in a freezer bag when packing to manage soot and protect other stuff

This open bottom design will burn the ground underneath-and drop hot ash on it, so you should also add a base plate or use on cleared soil

[craigprice]

P.s. If concerned about the burn underneath the stove, use a burn plate made of a disc of aluminium from a soft drink or beer can (weighs nearly nothing and fits inside the open base of the stove when carrying)