Bodging attempt: how to bend 7mm diameter Ally rod?

[Warthog]

I'm knocking together a stove adaptor to carry a trangia spirits burner. I involves bending aluminium rod.

I have a sneeky suspicion that if I just bend it as is, is could sheer.

Any suggestions on how to do it?

[Treadtrader]

When i used to mess about building trials bikes i was told "smear with soap, warm until soap blackens then remove heat and bend"

Worked for me.

[jasonbc]

I'm knocking together a stove adaptor to carry a trangia spirits burner. I involves bending aluminium rod.

I have a sneeky suspicion that if I just bend it as is, is could sheer.

Any suggestions on how to do it?

Aluminium shouldn't snap/shear when bending as it a flexible and maleable metal if you think or feel it is going to snap stop. Warm it up before you try it again being ali when you heat it up it won't go red the silver aluminium will just go a different shade of grey

[Warthog]

Fantastic!

Tomorrow, I'll set to work with a blow-torch, and pair of mole grips and a bar of Cusson's Pearl!!

Seriously though, thanks for the pointers: I'll give it a go.

[davsato]

depends, if its pure aluminium it'll bend like butter over quite a small radius, but if its light alloy it'll be much stronger and more brittle. it should bend ok through a quite large radius, but will work harden so get it right first time.
have a look online for "bend allowance" formulae for the length of metal you need to go round different radii and degrees of bend, and what radii different materials at different thicknesses will bend around.

[Warthog]

Hmmmm.

Might be easier, albeit heavier, to use a thin steel rod. That, at least, can be bent this way and that. After all this is only to support a meths burner in a sort of cradle for my wood stove.

[hotbulb]

I've not tried bending ally bar, but for annealing ally sheet the waiting for the soap to blacken trick is spot-on. And as mentioned above, ally doesn't go red-hot, it just goes runny! (you don't need to ask how I know this )

[Snaphappy]

Alloy will bend no problem but you cant correct the bend and bend it back
for your burner I'd use brass brazing rods or stainless steel rods, easier to work with

and why 7mm you could hang a pig on that

[Warthog]

Alloy will bend no problem but you cant correct the bend and bend it back
for your burner I'd use brass brazing rods or stainless steel rods, easier to work with

and why 7mm you could hang a pig on that

7mm was the smallest they had in the shop...

As it happens the bending was easy. What was difficult was getting the two extremities to line up; having only a G-clamp and pliers to lever with... Gave up in the end and went for a completely differnt design. Finished it today.

Thanks for all the pointers, all, but alas it was not the best for me on this occasion!

On the plus side, I have now got wood or meths as a burn option!

[Snaphappy]

Post is still no good without pics