Pipe for side bending iron

[dannyds]

Good afternoon,

I am building a side bending iron using a Wagner Furno 500 heat gun, which can achieve temperatures in the range of 150F-1200F. I plan to build a stand out of plywood and blow the hot air into a pipe with a cap on the end. I have read that galvanized steel should not be used, so I am researching other options.

Will the pipe at the link below stain the wood? It says black-coated steel. Is that the same stuff they sell at Home Depot that I bought for pipe clamps? If so, I know it will stain the wood.
https://www.mcmaster.com/44615K126/

Any other safe, affordable options?

Thank you,
Dan

[phavriluk]

When I made my pipe, I searched online metals dealers until I found a thickwalled aluminum pipe of the size I wanted.

[Rudy4]

Originally Posted by phavriluk

When I made my pipe, I searched online metals dealers until I found a thickwalled aluminum pipe of the size I wanted.

Aluminum will stain some woods and iron / steel pipe will also react with certain woods. I use a length of 2-1/2" hard copper pipe fitted with a 1/4" aluminum plug with 1/4" holes drilled in it. The plug was fitted to the inside diameter of the pipe and is anchored with three 1/8" diameter roll pins driven into drilled holes. Capped pipes can heat unevenly as there's nowhere for the heat to go.

I have a couple of similar smaller diameter pipes for tighter radius bends.

I went to a larger industrial plumbing shop and got the pipe for a couple of bucks. I've been using it for several years and it sets up in about 30 seconds. Everything breaks down in seconds and stores flat so it takes up little room in the shop.

Don't forget to make yourself up a backing strap as shown in the photo.

[dannyds]

Originally Posted by Rudy4

Aluminum will stain some woods and iron / steel pipe will also react with certain woods. I use a length of 2-1/2" hard copper pipe fitted with a 1/4" aluminum plug with 1/4" holes drilled in it. The plug was fitted to the inside diameter of the pipe and is anchored with three 1/8" diameter roll pins driven into drilled holes. Capped pipes can heat unevenly as there's nowhere for the heat to go.

I have a couple of similar smaller diameter pipes for tighter radius bends.

I went to a larger industrial plumbing shop and got the pipe for a couple of bucks. I've been using it for several years and it sets up in about 30 seconds. Everything breaks down in seconds and stores flat so it takes up little room in the shop.

Don't forget to make yourself up a backing strap as shown in the photo.

Thank you for the advice. What is the thickness of that pipe? Is it easy to bend into an oval shape if desired? The diameter looks bigger than 2-1/2" to me.

[BradHall]

I started with a 3” black pipe with a galvanized cap. I do use a propane torch. I always used a blue shop towel between the pipe and wood, spritzing is with water to generate a little steam. It worked, never contaminated the wood. I then got the LMI aluminum pipe and never looked back. Haven’t had any contamination issues. I have a friend with an electric one that serves him well. Another friend used a cut off from a sailboat mast that was already oval, with a bbq starter and it works for him, although he only builds dreads. I’m a mostly built it if I can guy when it comes to tools. Sometimes it’s just worth it to buy something tried and true. Good luck on your build.

[Bruce Sexauer]

I have used a 6’ long piece of 3” OD iron pipe for 45 years! I also use a Fox bender and an electric violin type hot pipe, but they are recent additions to the Arsenal.

[Rudy4]

Originally Posted by dannyds

Thank you for the advice. What is the thickness of that pipe? Is it easy to bend into an oval shape if desired? The diameter looks bigger than 2-1/2" to me.

The wall thickness of the pipe shown is approximately 1/16", so the actual outer diameter of the pipe is 2-5/8". A "2-1/2" pipe has slightly different outer diameters depending on the type of copper pipe is selected. Type "M" is thinner walled and Type "L" (shown in the photo) has increased wall thickness. The inside diameter is the same between types.

No, type L isn't "easy" to bend, but it could be shaped if that's what you really want. I simply switch to a smaller diameter for tight bends like a cutaway waste.

Ideally you'll have much better bends using the larger diameter because the contact area along the wood will be greater (even though you control heat along the bend by rocking your work) and larger diameter decreases your chance of creating lumps and ridges along the bend.

[printer2]

I used a heat gun for a fair number of sides. No problem using galvanized pipe at the temperature we need. I found it better if I let some of the air pass through. Don't put the heat gun right in the pipe as the heat of the pipe will melt the outer plastic. Lost a gun that way.

[redir]

Originally Posted by Rudy4

Aluminum will stain some woods and iron / steel pipe will also react with certain woods. I use a length of 2-1/2" hard copper pipe fitted with a 1/4" aluminum plug with 1/4" holes drilled in it. The plug was fitted to the inside diameter of the pipe and is anchored with three 1/8" diameter roll pins driven into drilled holes. Capped pipes can heat unevenly as there's nowhere for the heat to go.

I have a couple of similar smaller diameter pipes for tighter radius bends.

I went to a larger industrial plumbing shop and got the pipe for a couple of bucks. I've been using it for several years and it sets up in about 30 seconds. Everything breaks down in seconds and stores flat so it takes up little room in the shop.

Don't forget to make yourself up a backing strap as shown in the photo.

I've had the exact same set up as you have since 1992. I vaguely remember going to some metal shop and asking for some large copper pipe. When I told the guy what for he thought it was great and just gave it to me. Instead of an aluminum plug I just stick the top of a beer can in there.

As of last year I now use a charcoal lighter instead of the blow torch. But I still just simply mount the pipe in a vice. Simple solutions.

I also added a bending machine to my shop last year.

[Zigeuner]

For the guitars that I've built (9 and working on #10), I've used an aluminum pips that is 4" OD and 3-1/2" ID with 1/4" wall. I heat it with a barbecue torch that is mounted inside and I've use both natural gas form my house and also propane at various times. I monitor the temperature with a digital thermometer and adjust the gas to hold my temperature. (this will vary).

With the wood thin enough, say .090 to .100, the wood bends nicely once soaked for a bit in water.

Works for me. I'd post some pictures but it's very difficult on this site since I don't have a hosting site anymore.

[Brad Howard]

I use a 3"SS exhaust pipe extension with muffler clamps and some insulation to mount the pipe on a board which I clamp in my vice.

[dnf777]

If youre near a sailboat shop, they can cut you a short piece of aluminum mast. Round if you prefer, but mine has a slight teardrop profile. Aluminum heats quicker than iron or steel. I give mine a quick brush with medium steel wool before using to remove any ox, and havent had any wood discoloration issues.

[MC5C]

I use 3" truck exhaust pipe, probably 16 gauge, squashed into an oval shape. I use an electric barbque starter as a heat source. It was free and it works great.

[kmanuele]

I used a piece of 2-1/4" steel pipe, about 9" long, pre-threaded on both ends from HD. Added a flange on one end and a cap on the other. Flange is for mounting in a vice.
Got an electric barbeque starter, carefully bent it to fit inside the pipe.
Connected a 1 kW incandescent light dimmer mounted in an outlet box.

[Zigeuner]

Originally Posted by kmanuele

I used a piece of 2-1/4" steel pipe, about 9" long, pre-threaded on both ends from HD. Added a flange on one end and a cap on the other. Flange is for mounting in a vice.
Got an electric barbeque starter, carefully bent it to fit inside the pipe.
Connected a 1 kW incandescent light dimmer mounted in an outlet box.

I like your idea. I have a nice setup for Gas or Propane with an aluminum pipe, but switching to electric will be much safer since I don't like open flames in my shop when I can avoid them.

Dimmers are OK and they are inexpensive but a few years ago, I found an electric voltage regulator that is very nice as well. I use two of these in a dual track Model Railroad DC Power Pack and they are very linear and precise. With one of these controlling the voltage into a BBQ torch and a digital thermometer, you could set the temperature very nicely. See the link.

Thanks for mentioning this.


https://www.amazon.com/Yeeco-Electro...s%2C225&sr=8-6