DIY wood stove with a CPU fan?

[sirbingo]

Hey Y'all,

I've been thinking of making myself a wood stove but I want to incorporate a CPU fan.

Are there any out there on the net you can point me to?

Here are the stoves I have come across: http://www.imrisk.com/forge/forge.htm

:bse

[dessertrat]

You'll need to make sure to match your battery voltage to the voltage required by the fan, and make sure the fan is far enough away that it doesn't melt. Other than that, have fun!

[sirbingo]

Oops! I just realized I should have put this thread in the DIY forum. Doh! :datz Sorry Y'all

[NICKTHEGREEK]

The shortcoming of CPU fans is they are made to run on 12 VDC. If you use a 9V battery they run a bit slow but when the battery voltage drops below around 5 V they will not start to run. Finding a decent 12 V battery is pretty tough.
There's virtually thousands of applications out there look on line for one that draws about 0.08 to 0.12 amps. The current draw is inversely proportional to the air capacity, (fan speed and diameter). Too much wind is as bad as not enough.
I use them for tent fans just to keep some air moving, and wire wrap it to the mesh on my tent's eyebrow vent. I get at least 12-18 hrs life from a pair of paralleled 9 V cells.

[Bob S]

I used a CPU fan in my homemade ver of the WoodGas stove, it runs on 1.5 and 3-volts. How I made it work on 3-volt (hi speed) & 1.5-volts (low speed) is I took the fan blade off the CPU housing / motor. I went to Radio Shack and bought a 3-volt motor. I filled the fan blade hole (it broke when I pried it off the housing) with JB Weld, let it dry and then drilled a hole in the center just a bit smaller then the 3-volt motor shaft size. I then slipped the new motor shaft into the hole. It works great.

I also made a diffuser / protection plate for the fan blade. Two reasons for this, one: the fan blade is very close to the bottom of the burning chamber and it glows red when running. And also to divert the air up around the chamber into the holes drilled in the burn chamber for the gasifier (sp?) to work. I’m not sure I need the diffuser plate as the fan moves more then enough air to keep the heat away from the plastic fan blade. But I don’t run the stove without the fan on just incase there is too much heat. I have been using it a few times a week since November (4-months) and there is no melting of the plastic fan.

It works great, the fan doesn’t get hot at all, and it really puts out a lot of heat. Too much heat on high, low works good for cooking. High would work for boiling a large amount of water fast. As the batteries run down the stove actually becomes more useful because the air flow is lower and you can use high speed to cook with along with low speed.


Here is a web address (slide show) of some pictures the stove if you want to see them.

There are a few of pictures (top & bottom view) showing how I mounted the fan and motor.


http://photos.toast.net/slideshow.asp?user=n8spi&album=Wood%20Stove&index=1&timer=&PictDisp=0 (http://photos.toast.net/slideshow.asp?user=n8spi&album=Wood%20Stove&index=1&timer=&PictDisp=0)



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[dessertrat]

You can also use AAA or AA batteries stacked (in series) to increase their voltage output.

[NICKTHEGREEK]

I used a CPU fan in my homemade ver of the WoodGas stove, it runs on 1.5 and 3-volts. How I made it work on 3-volt (hi speed) & 1.5-volts (low speed) is I took the fan blade off the CPU housing / motor. I went to Radio Shack and bought a 3-volt motor. I filled the fan blade hole (it broke when I pried it off the housing) with JB Weld, let it dry and then drilled a hole in the center just a bit smaller then the 3-volt motor shaft size. I then slipped the new motor shaft into the hole. It works great.

I also made a diffuser / protection plate for the fan blade. Two reasons for this, one: the fan blade is very close to the bottom of the burning chamber and it glows red when running. And also to divert the air up around the chamber into the holes drilled in the burn chamber for the gasifier (sp?) to work. I’m not sure I need the diffuser plate as the fan moves more then enough air to keep the heat away from the plastic fan blade. But I don’t run the stove without the fan on just incase there is too much heat. I have been using it a few times a week since November (4-months) and there is no melting of the plastic fan.

It works great, the fan doesn’t get hot at all, and it really puts out a lot of heat. Too much heat on high, low works good for cooking. High would work for boiling a large amount of water fast. As the batteries run down the stove actually becomes more useful because the air flow is lower and you can use high speed to cook with along with low speed.


Here is a web address (slide show) of some pictures the stove if you want to see them.

There are a few of pictures (top & bottom view) showing how I mounted the fan and motor.


http://photos.toast.net/slideshow.asp?user=n8spi&album=Wood%20Stove&index=1&timer=&PictDisp=0 (http://photos.toast.net/slideshow.asp?user=n8spi&album=Wood%20Stove&index=1&timer=&PictDisp=0)



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The equivalent of how much does it weigh----How much current does the fan draw? Pretty slick idea.

[Bob S]

I haven’t weighted it but I would guess 1-pound (I picked it up and a 1-pound jar of peanut butter and they both feel the same.)

As far as power consumption, I bought the lowest powered motor I could find at Radio Shack that had a shaft on it (not a gear.) It draws just over1/10 of an amp (125ma) at 3-volts, and 80 ma at 1.5 volts.

Batteries last a a fairly long time.

[NICKTHEGREEK]

I haven’t weighted it but I would guess 1-pound (I picked it up and a 1-pound jar of peanut butter and they both feel the same.)

As far as power consumption, I bought the lowest powered motor I could find at Radio Shack that had a shaft on it (not a gear.) It draws just over1/10 of an amp (125ma) at 3-volts, and 80 ma at 1.5 volts.

Batteries last a a fairly long time.
Thanks, I went to the RS web site but the specs on the only 1.5-3V fan were virtually blank.

[Lint]

Here is a link you might like.

http://zenstoves.net/Wood.htm

I used a bushbuddy ultra on the CDT this year and it worked very well.

http://bushbuddy.ca/indexs.html

Cooking over fire occasionally took longer than an alcohol stove would, but I really enjoyed it. The smoke kept bugs at bay, and the need to collect dry tinder heightened my awareness during times of rain. I carried cotton balls soaked with petroleum jelly as emergency firestarter but only used them twice the whole way. It goes without saying, but using fire demands safety precautions lest you torch the woods!

I'm not a fan of campfires due to their impact on the surrounding area, but these little stoves only burn tiny sticks/pinecones for fuel, so you're not burning up every piece of downed wood like a campfire can.

[Bob S]

Pine cones don’t seem to burn that well for me as do small sticks do.


Maybe there is something wrong with the pine cones in Ohio. :-?

[Bob S]

Thanks, I went to the RS web site but the specs on the only 1.5-3V fan were virtually blank.


When you go into a Radio Shack store and look at the back of the package you will see the info on the motor (volts, amps, RPMs.) The local RS had 3-motors, the one (I bought 2, so I had one for a future project) I bought was on the shelve a while as the package looked old. But it works great. I can’t remember the price of the motor, but it was only a few dollars.

If you buy one of those hand held fans with soft plastic blades that run on 2 AA batteries, you could use the motor from it for a stove. These fans sell here for $1.00 in the spring time at several of the local stores. Rite Aid has them, Wal-Mart also.

If you have kids and they have some old broke toys that have motors in them, you could part out the toy. Don’t let your kid see you doing this. When my Son was little he never wanted to get rid of old broke toys, we would have to junk them after he went to bed.

If you took one of your kids toys apart for the motor, you would be looked at like you were an evil dad by your kid. :mad:

[NICKTHEGREEK]

When you go into a Radio Shack store and look at the back of the package you will see the info on the motor (volts, amps, RPMs.) The local RS had 3-motors, the one (I bought 2, so I had one for a future project) I bought was on the shelve a while as the package looked old. But it works great. I can’t remember the price of the motor, but it was only a few dollars.

If you buy one of those hand held fans with soft plastic blades that run on 2 AA batteries, you could use the motor from it for a stove. These fans sell here for $1.00 in the spring time at several of the local stores. Rite Aid has them, Wal-Mart also.

If you have kids and they have some old broke toys that have motors in them, you could part out the toy. Don’t let your kid see you doing this. When my Son was little he never wanted to get rid of old broke toys, we would have to junk them after he went to bed.

If you took one of your kids toys apart for the motor, you would be looked at like you were an evil dad by your kid. :mad:
Thanks again! I pick one up on my next trip and try it with different power supply fan blades. I have about a dozen old ones sitting around at work.