Stupid bending question - Am I doing it all wrong?

[slowlearner]

Coz I could, and coz using my $5 blow torch is so fun, I thought I'd have a go at bending some timber tonight. I used the following setup...



2" Thick wall tube with the torch blowing into the pipe on a slight angle.

I tried bending a 5mm thick offcut of vic ash I had. I found it bent ok, but the inside of the timber burned where it touched the pipe. The burn marks were also quite deep and even when I'd sanded them some they were still there. There was also some checking where the timber had touch the pipe.



Now Vic ash always burns easily anyway with the router or sander, but I wondered if I was doing something wrong. Should I be dampening the timber with a little water before bending it, or should I be be bending it dry?

[DarwinStrings]

They probably are not burn marks unless you had that pipe far too hot. Many woods will stain black when they come in contact with iron (especially iron and water) and Vic Ash is one of them. Many woods can be bent dry but with most a little bit of steam helps, some it will hinder (it will stain even more on that steel pipe if you use water).

Jim

[slowlearner]

right. So it was probably too hot then. Mmm. Will try again.

[DarwinStrings]

Here is a bit of Vic Ash, it has been sitting on the ground on iron fillings, no heat applied at all. The termite excavations in it are a few mill deep and there is still bits of stain in them, the stain runs deep.

Jim

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[simso]

5mm thick is pretty thick for bending

Most times my wood is about 2mm thick, I also back the wood up with a strip of stainless steel and I wet the wood prior to bending, sometimes Ill alfoil wrap it wet and then bend

Lots of tips and tricks, practice makes perfect

[liam_fnq]

I have to keep my gas torch as low as it will go to keep it from getting the pipe too hot.

[Nick]

A good indicator to the right* heat, I've always found (and is a 'standard' test), is to drop a few drops of water on your tube/iron and if the drops "dance" around rather than just turning straight to steam you are ready to bend.
Also as Steve stated, 5mm is a bit thick, 2mm is better and also I'd try spritzing the wood with a bit of water, no need to soak it just a couple of fine mists are adequate. A hand held/operated spray bottle is all I use. Also just wait until you feel the wood wants to bend don't try pulling it around your tube, it's a weird but satisfying feeling and you'll know it when you feel it but there's a point/moment where the wood almost turns to rubber and it just bends without much effort from you.




*= Different timbers bend at slightly different temps but I've always found the dancing drops a good place to start from.

[Taffy Evans]

I have always used an old coiled radiator/room heater element in my heating pipe, this is attached to an old oven thermostat control. When I've got the heat range I need, I can hear the unit switching on and off as I work. I also create as much steam as I can and sandwich the side timber. I don't use iron pipe. Well that's what I used to do now I use a Fox style bender, but still use the above method at times.

[ernieman]

A good indicator to the right* heat, I've always found (and is a 'standard' test), is to drop a few drops of water on your tube/iron and if the drops "dance" around rather than just turning straight to steam you are ready to bend.
Also as Steve stated, 5mm is a bit thick, 2mm is better and also I'd try spritzing the wood with a bit of water, no need to soak it just a couple of fine mists are adequate. A hand held/operated spray bottle is all I use. Also just wait until you feel the wood wants to bend don't try pulling it around your tube, it's a weird but satisfying feeling and you'll know it when you feel it but there's a point/moment where the wood almost turns to rubber and it just bends without much effort from you.
*= Different timbers bend at slightly different temps but I've always found the dancing drops a good place to start from.

About those dancing drops...
I'm using a aluminum bending iron and have always learned and experienced that dancing drops means your iron is too hot. Dropping a few drops on top of the iron and see that they sizzle, rather than dance. Dancing means that the iron is so hot, the drops don't get the time to "spread out".
But then again, I could be wrong...

The spray bottle is a good find! I always used a wet cloth, but that's always a bit messy...