Woodgas burning stove

[Whistle]

A while ago I experimented with a woodgas burning stove, there are lots of examples on you tube and through the "Zen alcohol stoves" site. The whole idea of free fuel and not having to carry fuel with you appealed greatly. Having made several different styles of pop can alcohol stoves I thought it would be fun to try building a wood gas burner...
I started by scouring the local homeware departments and found several suitable containers and useful items made from stainless steel . I know you can make them cheaply from empty food cans but I worried about rust and longevity, besides stainless is so much more attractive and easy to clean Hahaha...
I found the best value items from Wilkinsons and after purchasing a step drill bit set about a couple of different designs using different containers and draining stands...

http://a1.sphotos.ak.fbcdn.net/hphotos-ak-snc6/282458_122555017840326_100002574849870_144564_4429 527_n.jpg

http://a5.sphotos.ak.fbcdn.net/hphotos-ak-snc6/282088_122555127840315_100002574849870_144566_4464 996_n.jpg

http://a3.sphotos.ak.fbcdn.net/hphotos-ak-ash4/281984_122555211173640_100002574849870_144567_3942 820_n.jpg


http://a6.sphotos.ak.fbcdn.net/hphotos-ak-ash4/262802_122555317840296_100002574849870_144569_1565 235_n.jpg

http://a8.sphotos.ak.fbcdn.net/hphotos-ak-snc6/252050_122555624506932_100002574849870_144575_6177 527_n.jpg

http://a8.sphotos.ak.fbcdn.net/hphotos-ak-snc6/252050_122555624506932_100002574849870_144575_6177 527_n.jpg


http://a6.sphotos.ak.fbcdn.net/hphotos-ak-snc6/281319_122555957840232_100002574849870_144583_4671 464_n.jpg

http://a7.sphotos.ak.fbcdn.net/hphotos-ak-snc6/252139_122556027840225_100002574849870_144584_6254 687_n.jpg

Yeah get that kettle on !!!

There was an air flow issue which was easily rectified by enlarging the holes round the pot stand ring.... in the photo with the kettle you can just see wood gas vapour swirling round some of the air inlet holes at the container base.
Overall I was quite pleased with this first attempt. It brought a litre of water to the boil in about 12 minutes with enough fuel left to maintain a rolling boil for another 10 and then continued simmering for nearly half an hour on the charcoal created by the primary burn!
In use the lid holds everything together , the pot stand ring reversing and fitting inside with a full chamber of fuel , I used apple wood chips and lit them with a few ml of alcohol and firesteel.
I was encouraged enough to set about the improved mark2 version...Perhaps a thread continuation???

[JEEP]

Very very nice! Well done :happy-clapping:

[Metal mug]

Very Good. It's really well made.

[Whistle]

Thanks for the positive comments JEEP and Metal mug , means a lot to a newbie like me !!!

Here are some more photos of the mark2 version using more stainless containers from Wilkinsons , a slightly smaller , shorter , outer container and a squarer inner which gives a greater volume for fuel than the tapered cutlery drainer in used in mark1.

http://a5.sphotos.ak.fbcdn.net/hphotos-ak-ash4/229770_122559017839926_100002574849870_144598_4530 3_n.jpg


http://a7.sphotos.ak.fbcdn.net/hphotos-ak-snc6/262872_122559111173250_100002574849870_144600_3414 342_n.jpg


The holes here , 3mm diameter , were later enlarged to improve the airflow through the grate...


http://a1.sphotos.ak.fbcdn.net/hphotos-ak-snc6/229783_122559187839909_100002574849870_144601_5866 056_n.jpg


http://a5.sphotos.ak.fbcdn.net/hphotos-ak-ash4/226081_122559274506567_100002574849870_144603_4453 722_n.jpg


http://a8.sphotos.ak.fbcdn.net/hphotos-ak-snc6/224510_122559401173221_100002574849870_144604_1246 65_n.jpg


http://a8.sphotos.ak.fbcdn.net/hphotos-ak-snc6/224510_122559401173221_100002574849870_144604_1246 65_n.jpg


And here are some totally gratuitous swirly flamey piccys Haha! .... Please note the enlarged breather holes in the pot stand ring , stove burns better with pot on now.


http://a1.sphotos.ak.fbcdn.net/hphotos-ak-ash4/283397_122592077836620_100002574849870_144710_2706 672_n.jpg


http://a5.sphotos.ak.fbcdn.net/hphotos-ak-snc6/223727_122592161169945_100002574849870_144712_2143 148_n.jpg


http://a2.sphotos.ak.fbcdn.net/hphotos-ak-snc6/284975_122592251169936_100002574849870_144714_5462 681_n.jpg


http://a2.sphotos.ak.fbcdn.net/hphotos-ak-snc6/284975_122592251169936_100002574849870_144714_5462 681_n.jpg


http://a1.sphotos.ak.fbcdn.net/hphotos-ak-ash4/283397_122592077836620_100002574849870_144710_2706 672_n.jpg

[Ashley Cawley]

Brilliant stuff! I never knew a wood-gas stove could be made so easily. Thanks for sharing :)

[Whistle]

Thanks Ashley , really helps having the step drill bit for the larger holes .
Drilling holes in thin stainless with normal HSS bits always left me with irregular figure 8 shaped holes before i got the step bit .
The hardest thing was the odd looks from store assistants when you try putting the pots together to see if they fit ... even worse when you get the digital calipers out !!! Hahaha !!! Cheers Whistle

[LandRoverMatt]

wow looks really good

[m0txr]

Brilliantly done, and still going strong I bet.

[Marvell]

That's fab. I have a wine cooler that I want to turn into one. I was wondering, as a point of design, are the holes in the outer skin higher or lower than the base of the inner skin?

[ian c]

Very nice, cheers for the photos showing the different stages.

[Tony1948]

Great jobT^

[Fletching]

Looks like a really good job done there mate.

T^

Steve :)

[Hushwing]

.... I was wondering, as a point of design, are the holes in the outer skin higher or lower than the base of the inner skin?

Sorry - you'll need to brew up - this has a long lead-in to the point of my answer!!!

Having been given some Christmas dosh I was looking to buy a kelly kettle or ghillie kettle or ilk but then decided upon the wild woodgas stove.
http://wildstoves.co.uk/wood-cooking-stoves/wood-gas-camping-stoves/wild-wood-gas-stove/ - these guys also have a pocket version of the honey stove. You can get a comparison of wood burning stoves here. Long scientific document but quite interesting reading - http://www.pciaonline.org/files/Test-Results-Cookstove-Performance.pdf

I had trouble getting my woodgas stove to work well at first but now got the hang of it and think it's brilliant - use it all the time. Think the double burn thing helping to make it more smokeless is great. The point, though, is that it costs a wee bit and I thought I might be able to make my own cheaper version - not in the same great league as Whistle's (I recognise so many of those parts - can't wait to have a go). I also thought it might be good to see how small I could produce one. So used a standard soup tin and a small peas tin, as an experiment. The soup tin had a slight lip. The pea tin top edge was folded outwards and this folded lip sat on top of the soup tin's lip. The pea tin inner was therefore slightly shorter (as in the proper stoves). see pictures. The funny fawn ring round the top is the car weld heat resistant epoxy stuff (not really needed but does give a neater seal).448444854486

NOW here's the answer - finally :-) - I found:
1. on mk 1 that if the holes were above the line of the base of the inner skin they aren't as effective in giving a draught upwards.
2. Also found that the manufactured woodgas stoves and ones like Whistles are at optimum size (for compactness and effectiveness). My tins were so small that I spent all the time feeding them with the smaller bits of wood that I had to use (and it was harder to feed them with a pot on top!).
3. Have even experimented with just sitting the pot directly on top of the can (ie without a space and pot stand) so that the wind didn't blow out the flame or produce a down draught but that (obviously duh!) cut a lot of the air flow. So tried drilling some holes in the top of a section of soup tin to operate as a stand sitting on top of my woodgas stove but again not as effective as having the pot stood with a proper space between stove and pot base.
4. Hope sometime see if I can make a garden barbecue size woodgas stove ie go bigger now to see if can get all the benefits of a woodgas stove but at super duper size and efficiency! converted gas fire bottle???

Long time getting there but hopefully some useful how-not-to-design info - I have this knack of working through all possible mistakes to produce something!!!

[Martin]

Nice write up there Hushwing and thanks for going to all the trouble so that we don't have to. :)

Martin

[Hushwing]

Thanks for that - especially thanks for the patience to read it! :D

I like to think of my failed experiments as an idiot's guide..............

[Hushwing]

Should have added, also, that have experimented with trying above stoves with a computer fan (by from folk like Maplins) and a 9V battery ('square battery') to add a super up-draught (a sort of hobo version of the Wood Gas Stove XL/LE stoves with bulit in fan) It slightly improves the initial burn and keeps things moving but not totally essential. The other thing is that these fans need to be fairly closely positioned under the stove and if the wind is strong enough to produce a down draught, the computer fan housing might melt due to hot embers falling on it - I know as I already wasted one - though mesh might protect it. I'm guessing this arrangement might also work with things like the honey stove etc (if burning wood).

PS idiots guide advice #2 - if you do use the fan/battery arrangement stated previously - make sure the fan is turned the right way round and is blowing air up and not sucking it down - it melts it!! (not that I made that mistake or ennyfing!). Because computer fans are used to extract or suck out hot air from the PC it might mean turning the fan 'back to front' in its housing to give the updraught.