# Hollow form alcohol campfire?



## sprior (Aug 31, 2008)

An old friend is visiting the weekend and since I've been playing with logs lately she sent me this idea where you take a log, make 6 cuts in it with a chainsaw, stuff newspaper in the kerfs and use that as a campfire.

Now this may be out there, but I've seen a few alcohol based patio fire features on some DIY shows. I was thinking of taking a log, putting it on the lathe and then turning it to a fairly quick hollow form which I would take outside onto the patio, pour some denatured alcohol in it and then use that as a disposable patio fire feature for entertaining. It seems a bit farfetched that anyone would have done this before, but in case I'm wrong has anyone here thought of something like that? I'm interested in how deep the hollow should go to contain enough alcohol, but what proportions of hollow to hole size would keep the fire burning for the longest.

Any ideas?


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## Itchytoe (Dec 17, 2011)

I would be concerned that the vessel may not be as solid as it should be. A crack letting alcohol leak could result in some very unfortunate but pretty flames . Alcohol does burn pretty well. You also have to remember that the vessel would be wooden, and could possibly crack while on fire resulting in those same very unfortunate results.

I'd suggest a wooden box built around some other container known to withstand the stresses involved with an alcohol fueled flame. Maybe build a conical or cylindrical cover would work well.


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## sprior (Aug 31, 2008)

Good points Itchy. I'm thinking that if I put a log a little over 12" long in the lathe I'd leave about half of it as is as a rough base and then turn the top half into the form shape. That way the piece would look like a form sitting on a log as a base. The cut in at the middle where the rough part starts could even be slightly bowl shaped to catch any alcohol leaks from the vessel part. The vessel itself would be left pretty thick mostly because this would be a fast piece so no time spent making it thin. I'd at least sit this whole thing in some kind of tray or fire pit to catch any leaks.

My main thought is what shape/hole size to use so that the alcohol doesn't burn too fast and how big the hollow needs to be to contain enough alcohol so I'm not refilling it every 30 seconds.


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## chrisgerman1983 (Jan 17, 2009)

Once you have your vessel you could hammer some tin inside to seal the log from burning? As long as the alcohol doesn't absorb it will be safe but if it seeps into the pores of the wood and you let the level run down it would burn your vessel.


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## sprior (Aug 31, 2008)

The idea was for this to be a disposable and relatively quick vessel for outdoor entertaining. My bigger problem would be how to get rid of what's left if it didn't end up completely burning.


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## sprior (Aug 31, 2008)

Think of it as the wood turners equivalent of an ice sculpture for a party.


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## WolverineE (Apr 23, 2012)

I've seen this before! But... I've never done it myself.

It's kind of like the way the Native Americans used to make Canoes out of logs. They would make a trough that was small and then light fires to hollow out the log. 

I think you have 3 things to consider... Basically, you're just building a combustion chamber. Here is what I think the basic math would be.

Area for the holes:
If you cut a log that was 2 foot diameter by 30" tall then if I were doing it I would keep the holes within a circle that would be <1/3 of the diameter of the log (6-7").

Depth of holes:
Then, I would keep the depth to <1/3 of the height of the log (10"). 

Bore diameter of the holes:
Last, I would think that the bore diameter of the holes should not exceed 1/3 of the total volume of the combustion chamber. So, if the total combustion chamber area is a 6" circle by 10" deep you would have a potential combustion chamber volume of about 1.2 gallons. If you bore 1/2" holes that are 10" deep you probably only need about 4 of them... rough math... You may want to drill smaller holes.

Once those holes burn through a bit you'll have a nice little pit. 

Post pics!


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## duncsuss (Aug 21, 2009)

Just make sure you don't create something that explodes.


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## sprior (Aug 31, 2008)

Yeah, that's high on my requirements list. Part of my safety protocol is to make sure I don't utter the words "watch this!" - that's a deadly phrase.


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## mackem (May 20, 2007)

sprior said:


> Yeah, that's high on my requirements list. Part of my safety protocol is to make sure I don't utter the words "watch this!" - that's a deadly phrase.


Make sure you turn a beer holder first. :shifty::laughing:


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## WolverineE (Apr 23, 2012)

> Yeah, that's high on my requirements list. Part of my safety protocol is to make sure I don't utter the words "watch this!" - that's a deadly phrase.


'll r

lol... Post Pics... I'm curious how this works out. I don't think that you'll really have an issue with denatured alcohol... but... stand back when you light it!


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## sprior (Aug 31, 2008)

The prototype. Done in about 90 minutes.

When I try to light it success will be posted as a pic here, failure would be on YouTube...


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## Bonanza35 (Jan 20, 2011)

How much did you hollow?  I can't wait for your report. So many possible outcomes...


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## Hammer1 (Aug 1, 2010)

You know that alcohol flames can be invisible and that the fumes may be explosive, don't you? In racing where alcohol is used as fuel, there can be a raging fire and no body can see it, very dangerous.


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## sprior (Aug 31, 2008)

I knew that alcohol flames can be invisible in daylight so we didn't light it until dark. I didn't hollow it as deep as I had originally planned because the inside of the log was kinda punky and difficult. I completely filled the cavity with alcohol so there could be no explosive buildup of fumes in the chamber. The attached picture was taken with a tripod and very slow shutter speed (it was pretty dark).

I'm quite happy with the result, the flame burned for at least 90 minutes and then just went out, the wood didn't stay on fire. One thing that did happen was because the interior of the log was in worse shape than I expected some of the alcohol seeped all the way through and out the bottom, so we just lit it to get rid of it. So the bottom of the log got a little charred, but no big mess - the log was sitting directly on top of a bluestone patio.

So if I was inviting a few friends over again with the expectation of sitting around the patio and talking I'd do this again, just with a log that wasn't as funky in the middle. It didn't take that long to turn (a little over an hour) and I think it was a nice centerpiece.


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## duncsuss (Aug 21, 2009)

:thumbsup: :thumbsup: :thumbsup:


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## Kenbo (Sep 16, 2008)

Wow. I really didn't have any useful input while this thread was going on but the result is pretty cool I have to admit. I love it. Good for you for thinking outside the box. Great work.


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## mackem (May 20, 2007)

I must admit I was thinking "what's the point" in doing this,
but, I have admit I'm very impressed with the result.
Well done sir. :thumbsup::thumbsup::thumbsup:


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## sprior (Aug 31, 2008)

What's the point? You get the fun part of turning something quickly, skip the annoying sanding and finishing part, don't have to worry about cracking, and then get to light something on fire and hang around with friends and stare at it... Tha's total goodness all around :laughing:


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## sprior (Aug 31, 2008)

I might have said this elsewhere but not here - think of it as the turners equivalent of an ice sculpture for a party.


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## sprior (Aug 31, 2008)

Here's a little post mortem on my torch turning. If you look carefully you can see how far I pre-drilled with a 5/8" bit, but I didn't get anywhere near that far because guests were coming and the wood in the middle was coming out fuzzy instead of 
as shavings. I filled the chamber completely with alcohol and it burned for about 90 minutes even with some seeping all the way out the bottom. If I had actually managed to hollow as I had planned and filled it completely that thing would still be burning.


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## WolverineE (Apr 23, 2012)

Would you mind posting the plans and more pics?


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## b00kemdano (Feb 10, 2009)

This is a cool idea! 

I'd drop a tin can in there to contain the fuel, though. It'd still be disposable.


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## Nate Bos (Jan 11, 2012)

That is awesome man! Nice thinking!


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## sprior (Aug 31, 2008)

WolverineE, there are no plans for this project besides try not to kill yourself on the lathe and don't get burning alcohol on you. All the pictures that exist are also in this thread. Start with a log safely on a faceplate, turn the outside as desired (I used a bowl gouge for the outside), then hollowed the inside using the Munro Hollower2 (after pre-drilling the center).


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## Horatio (Apr 4, 2012)

That's really slick and an ingenious idea. I may have to try that next time I have people over to the backyard.


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## rok3269 (Feb 4, 2009)

As an added safety feature, the base of your alcohol lamp could be placed into a container of gravel or even ground glass which has the added effect of reflecting light. this way if the alcohol does soak into the wood and burn you wouldn't have to worry about any damage to the flagstone patio and a alcohol leak would also be contained as well to avoid a potentially worse case scenario. I know this was supposed to be a quickie item to make, use and after discard, but the base could be reused and the wood light could be removed and discarded. thus you would have a reusable "safety box" to hold your "disposable" alcohol lamp.

just my 2 cents worth


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## sprior (Aug 31, 2008)

I agree completely rok and if I hadn't run out of time and patience I would have at least put it in a foil roasting pan with some sand in it. The other factor was that we're planning to replace our porch soon anyway so I didn't care much. Because of the poor wood in the center alcohol did leak through and we just decided to ignite it to burn it off, but it left no mark on the stone afterwards.


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## sprior (Aug 31, 2008)

Well go figure, looks like someone has made a product out of a disposable log patio fire. I thought it was alcohol based at first, but after going to the website I think it's all wood cut to make it easy to light.


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## Cicolid (Apr 10, 2010)

Saw this near Banff in Canada. It is a pine log, with a hole ¾ the depth. It has a hole drilled in the side about 5cm from the base which connects with the first hole.
Shaving soaked in wax are used to light the fire.
It worked great. 

HTH

Col


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## dognobbler (Sep 18, 2012)

Nice. Could you hollow out like you did and drop in a tiki torch can, or a long slim glass candle holder and then have the same result but the wooden part would be protected?


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## sprior (Aug 31, 2008)

I don't see why not, though if using glass I'd make sure it was Pyrex so it didn't shatter from thermal shock. I was going for completely disposable one time use so those things didn't matter.


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