Thread: Suggestions for Timber Bending Iron

Use a hot pipe. The metal for mine was scrap so cost nothing. I welded a steel rod onto the pipe so I could hold it in the vice. Heat it with a gas torch. I made it 22 years ago and am still using it.

Thanks for your reply mandoman. Did you put an end on the pipe, like a cap? About what diameter pipe did you use.

Paul

There is no end on the pipe. I actually have two pipes of different diameters, one for more gradual curves and the other for tight curves. One is 100mm in outside diameter, the other is 50mm. Together these two pipes have made almost 200 instruments.

Hi Mandoman, wow, 200 instruments, that is very impressive. So the heat doesn't escape, the torch just heats the pipe and it stays at a desired temperature, very interesting,

Paul

Originally Posted by Pauls321

Thanks for your reply mandoman. Did you put an end on the pipe, like a cap? About what diameter pipe did you use.

Paul

If money is short then a home made gas heated pipe will work. However if you can afford it an electric iron has a few advantages...the main one being able to accurately control the temperature of the iron. Ive got two electric irons I bought from Stewmac/LMI. Sure they cost a few dollars but they've been working faultlessly for the last 10 years.

Hey there Mandoman,

Today I called in to see a bloke who owns a metal industrial engineering place. I got him to make me up a 6 inch length of a 4 inch diam pipe with a rod welded inside, plus the same for a 2 inch diam pipe. Any clues on what torch to get and length of time you heat the pipe up etc,..??.

Regards
Paul

I made this bending iron out of new and scrap materials.

The iron itself is a 200 mm long x 65 mm diameter solid aluminium rod, bought new from a metal merchant. I drilled a 9 mm dia x 150 mm deep hole through the centre to take 9 mm x 150 mm (200W) electric cartridge heating element. The hole that you see at the base of the iron is to connect a thermocouple to the terminals on the control box. The control box provides power to the bending iron using a computer power cable. The control box gets power from the mains socket through a second computer cable (the ones with a D shaped plug at one end). When all is connected together correctly, to the CX100 PID controller, it will maintain the iron at whatever temperature is set. I am told that 150 degrees is about ideal for bending guitar sides.

Aluminium rod was $40
Heating element $15 from ebay - the heating element needs to be in close contact with the aluminium rod - I used heat transfer compound ~ $5 a tube
Temperature controller + thermocouple $25 from e-bay
~$10 for the male D connectors and screw terminals.

I also had to buy the extra long drill bit ~ $20, but now I have that...

All up about $100 - I think its better (better temperature control and faster heating time) than the one available on the net for ~$500

The switches plugs and power cables I had lying around in the shed

200W is overkill, but using lower power rating heaters means that it takes a long time for the iron to come up to temperature - a complaint I saw regarding the commercially available iron.

There is a video on YouTube where someone made something similar but used a tube for the iron and packed aluminium foil tightly around the heating element. Cost would have been the same (lots of Al foil = $$$), but avoids a very tricky 9mm x 150 mm drilling job

I've turned it on and it works well (comes up to temperature fast and controls to within 2 degrees) but have not bent any sides yet. I want to make a ukelele.

Hope this gives you some inspiration... It was tricky build (150 mm hole - wiring of the controller), but it was kind of fun.

Jorge

PS: If you have not worked with electricity or wired up a controller before - you should probably seek help before you do it this way.

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I have a Primus gas torch. Time to heat the pipe will vary depending on the size of the pipe and the heat produced by your torch. Drop a few drops of water on the pipe and if they bounce and sizzle off then it is the right temperature. You use the thermal inertia of the pipe, so it will cool as you bend Stop bending and heat again. You will soon get the nack. Practice on scrap.

Originally Posted by GarciaJ

I made this bending iron out of new and scrap materials.

The iron itself is a 200 mm long x 65 mm diameter solid aluminium rod, bought new from a metal merchant. I drilled a 9 mm dia x 150 mm deep hole through the centre to take 9 mm x 150 mm (200W) electric cartridge heating element. The hole that you see at the base of the iron is to connect a thermocouple to the terminals on the control box. The control box provides power to the bending iron using a computer power cable. The control box gets power from the mains socket through a second computer cable (the ones with a D shaped plug at one end). When all is connected together correctly, to the CX100 PID controller, it will maintain the iron at whatever temperature is set. I am told that 150 degrees is about ideal for bending guitar sides.

Nice work on that bending iron. The only comment I'd make is regarding the shape of the iron. A circular iron means that range of bends you can do are limited. The Ibex style iron has an oval shape so you've got a wide range of bending radii and you can also screw on a smaller radius add-on for doing really small stuff and binding. A gas powered pipe style bender with a variety of pipes of differing diameters would also be more versatile.

Ibex shape was not possible for me without a lot of fabrication which I was not able to do with current equipment. I regretted not using a smaller diameter rod... However, I CAN make another smaller diameter iron quite easily and attach it to the same temperature controller as these are "modular". With a bit of a fiddle I can even use the same heating element and mount. 65 mm is OK for the current project... I'll see what the future holds.

Sent from my C5302 using Tapatalk

Hi Jorge and Mandoman.

Thanks for all this advice, I will have a play with the steel pipes when I get them and then buy a gas torch.

And Jorge, Your invention would be a bit out of my league, looks good though,

Paul

Originally Posted by Pauls321

Hi Jorge and Mandoman.

Thanks for all this advice, I will have a play with the steel pipes when I get them and then buy a gas torch.

And Jorge, Your invention would be a bit out of my league, looks good though,

Paul

No right or wrong way to do stuff... just different ways... Enjoy the build.

Jorge

One tip when deciding on pipe diameter....make sure it's slightly tighter than the minimum radius bends you'll be doing. Especially important when bending cutaways by hand like I do.

Originally Posted by kiwigeo

One tip when deciding on pipe diameter....make sure it's slightly tighter than the minimum radius bends you'll be doing. Especially important when bending cutaways by hand like I do.

What kiwigeo said. My 65mm iron will be OK for my tenor ukelele project as it has a classic uke shape. But it would not be able to bend the cutaway profile in my daughter's Ibanez AEG1ONE - which is pretty much a 50mm "U" bend using this iron. In fact the pipe/iron diameter needs to be smaller than the intended bend radius, because the bent wood will spring back a little.

Incidentally, I saw an old wood/coal fired iron... the iron is the chimney over a small wood burner, which stood high of the bench or floor on 4 legs... small bits of scrap wood are plentiful around any wood shop right?

My problem with torches and fire is the lack of control over the heat... If the conditions are different every-time you use it, how do you become proficient at using the tool?

Jorge.