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Hello, folk,
I'm in the process of my first acoustic build. I bent the sides using an aluminum pipe with a charcoal starter shoved down the end of it. I put it in a 2x4 wooden frame. You can see the basics of it in the pic below; very simple.

It works great. the problem i have is that the wood is getting very hot, to the point of possible fire. Since I live in a trailer and am doing this in my back yard, I'd love to avoid that. I am passed the side bending process, so will not use it until my next build, but it is a concern I need to address before that comes.
I have asked around to several people about putting some type of material between the pipe and the wood, and no one has been able to help me figure it out.
I'm thinking that I could fold over some aluminum foil until it was fairly thick, and line the frame where it meets the pipe with that.
Do any of you think that will work, or do you have any other suggestions. BTW, budget is very small.
Thanks.

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Mike

The only thing nescessary for evil to thrive is for good men to do nothing.

My setup is similar to yours. I use a router speed controller from Harbor Freight to adjust the temperature of the charcoal lighter.

https://www.harborfreight.com/router-speed-control-43060.html

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sweat the small stuff.

On second read, maybe I misunderstood your problem. Either way, maybe that would help.

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sweat the small stuff.

Yes, I have a temperature control on it, but I find that the Sapele I prefer at the moment likes it wide open. At least this set did.

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Mike

The only thing nescessary for evil to thrive is for good men to do nothing.

Yeah, seems like you could just lower the temperature with something like a router speed controller, but if it won't bend at lower temperatures what can you do... Keep a fire extinguisher handy.

Dig your outdoor shop! Reminds me of that jungle guitars guy in Goa.

Pat

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Pat

Pat, thanks. I love building outdoors. The only issue is no humidity control, and winters here in Virginia. I have to do certain steps at certain times of year. Makes the work slow.
For example, I had to glue, thickness and brace the top and back and close the box indoors, when winter and the furnace lowered the humidity to 40% or so. Had to wait a couple of months for that.
But this is a first build; I'm sure I'll get my building process in order so that I can make better use of my time.

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Mike

The only thing nescessary for evil to thrive is for good men to do nothing.

High temperature gasket material, fairly thick, like for a car engine could help if placed between the pipe and the wood.

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The name catgut is confusing. There are two explanations for the mix up.

Catgut is an abbreviation of the word cattle gut. Gut strings are made from sheep or goat intestines, in the past even from horse, mule or donkey intestines.

Otherwise it could be from the word kitgut or kitstring. Kit meant fiddle, not kitten.

Yeah, if you time it right you can definitely do it. Probably would make sense to work in a small batch.

Pat

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Pat

Thanks, Colin.

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Mike

The only thing nescessary for evil to thrive is for good men to do nothing.

If you don't mind the pipe pointing to the side instead of forward, you could use L-brackets like mine.

Dennis, do the brackets get hot enough to scorch the wood? How far away from that base is the bottom of the pipe? Can I get a side view?
I know that's a lot of questions, sorry.

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Mike

The only thing nescessary for evil to thrive is for good men to do nothing.

I don't have a side photo handy, but the gap between pipe and wood is pretty small, about 1/8".

The brackets don't even get too hot to touch. They don't have much contact area with the pipe so not much heat gets into them in the first place, and they're thin with a lot of surface area so it dissipates into the air before building up.

If you can find a derelict cooking range you might be able to take the rope gasket from around the oven door and wrap that around the pipe where it passes through the wood. You can - buy - wood stove door gasket kits (Home Depot) but for me buying has always been a last resort for home grown tooling.
Another possibility would be an asbestos welding blanket, but that might be harder to come by.
Fire brick might also work.

A few bucks worth of all thread.

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My memory is so good, sometimes I remember things that never happened.

I mostly use bending blankets and molds, but when I'm using my electric pipe or my propane one, I just lay a piece of cloth on the pipe and use a spray bottle to wet it. Gives you hot steam and keeps the wood from scorching.--Bob

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“ The meaning of life is to find your gift and the purpose of life is to give it away” Pablo Picasso

If you like the wooden part of your setup just get a couple of roof flanges for water heaters. Kind of like installing a stove pipe through a wall. I welded a bracket on mine so I could put it in a metal vice.

Awesome idea!

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Mike

The only thing nescessary for evil to thrive is for good men to do nothing.

I have a similar setup as you but I, too have metal brackets attaching the pipe to a board/mount. I have a temp reducer but had to go full seed for effective bending. I saw a setup where drywall was used as insulator between pipe and wood. Sure paper backing burned off.

Durock (cement board) is more fire resistant than regular drywall, if you decide to tinker with the idea of a drywall layer.

Good to see you getting around to an acoustic, Mike!
Good luck!
Alan

When I need to use the iron pipe or whatever you want to call it here is a tip I will pass along.
Like Bob Gleason I use a wet towel and I also found using a steam iron on top also helps . My method was soak the towel and start my bend. Use the cloths iron on top with steam or wet paper towels.
Once I feel the wood giving I switch to a slat to bend around the iron and ditch the water and go dry to set the bend
this speeds the bending process but there is a knack to holding that curve just right. So any tweaking you can use the steam iron on top and use the pipe to dry and set

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John Hall
blues creek guitars
Authorized CF Martin Repair
Co President of ASIA
You Don't know what you don't know until you know it

Alan, thanks! It's great to see you back around these parts!

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Mike

The only thing nescessary for evil to thrive is for good men to do nothing.

Thanks, John!

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Mike

The only thing nescessary for evil to thrive is for good men to do nothing.

Looks like a nice spot to get into some side bending.
Working out doors is great! I do it too. I use a bulb in a pipe. It doesn't get very hot and take more time but it also stops the guitar sides from getting scorched.
going slow is better and getting the wood the right thickness is a must. Using this slow method once the pipe gets to the optimum temperature after being on for about 20 minutes wood bends easily and as quick as one would want with no burning. It is just a 60 watt bulb. Although the bulb is shorter than the pipe the whole length gets up to temp.
Maybe Using the hot wire element it would be best to insure it is insulated from the pipe and also stick a baffle in the end like I did made of part of a beer can. That way the heat can be controlled much easier and you would not have to have the thing set to full. I used to use one too and controlled the heat by plugging and unplugging it. This bulb idea is much better and safer IMO. If you need more heat to work faster you could up the watts of the bulb.

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You just pick up a chord, go twang, and you're got music. -Sid Vicious

I remember 25 years ago trying to come up with a solution to this problem and I thought for now I'll just hold the pipe in a vice. 65 guitars later and I still use this simple set up

A fire extinguisher is ALWAYS nearby.