Metal roll cages

[Mad4kits2]

Hi folks,I have some spare 1.7mm (roughly) aluminium hollow tube I want to make into roll cages.

How do I A)bend them and B)do not get any kinks on the bends.Thanks

[Alan R]

One trick that I believe plumbers use is to insert a smaller diameter spring into the tube prior to bending it. This reinforces the tube and generally stops the kinking.

 

Cheers, Alan.

[Fastcat]

Hi,

       It might be better to use solid rod if possible. If you anneal it carefully it should bend easily. You don't say how you intend to do the joints. The advantage of tube is that they can be pinned and glued but that's harder with rod. Maybe think about using brass and soldering the main joints. Still, you can't have everything.............................

 

Dave

[Chrissy_J]

You can buy spring formers that you slide inside the tube to be bent, or slide the tube into, to prevent a kink. They come in a set of different diameters.

Think they're made by KS Metals ... I got mine from here, for making motorcycle exhausts, but haven't used them yet.

 

https://maccmodels.co.uk/tools-drills-taps-etc/tools/tube-bending-springs/k-and-s-bending-springs.html

[noeyedears]

good luck getting a spring in that little tube 🤔

you could try annealing the tube, but it is liable to go from hot tube to molten mess very quickly.

heat ti up slowly, rub a bit of wood on it and when it starts to discolour the wood stop and let it cool down slowly.

 

i did a simple cage for an F40 but just used straight runs and butted the ends, filling in any imperfections with CA.

[krow113]

Tube bending is one of the  most mis-informed areas in model building.

The springs from KS metels go on the OUTSIDE of the tube.

Inserting anything into the tube to prevent the wall collapsing or kinking , just means that you usually forfeit whatever you insert as it wont come out.

Pounding sand into the tube is the dumbest "technique" , it wont work either.

I've been involved in the actual bending of tubing for a lot of my work.

For exhaust pipes 'U' bends are purchased or made and the sections cut to suit.

Here is a bender from Robbe I used in the making of exhaust and some bends:

Sectioned pipes and on the model:

...to the moon , Alice!

Here is a link to the model , a Top Fuel Harley Hillclimber. There is a TON  of info and you can watch me  make exhaust pipes.

http://www.kitmaker.net/modules.php?op=modload&name=SquawkBox&file=index&req=viewtopic&topic_id=240355&page=1

For a roll cage I would use rod and skip the tubing problems.

Edited January 7, 2019 by krow113

[noeyedears]

The springs go on the outside?😯...They go on the OUTSIDE!😳...Of course they go in the outside,😖 how the hell didnt I realise that?🙃

I do like that little bending tool

[David M]

krow113,

Thanks for your heads up. I tried searching for a bender like yours but have had no luck.

Robbe do not seem to have one...any ideas for a source?

David M

Sydney, Straya

PS: Nice hillclimber BTW!

[krow113]

Thanks David.

I got it at my LHS in Vancouver , Canada.

Robbe does tools & equip for the RC crowd. That's what the bender shown is for , doing fuel lines etc for radio control.

Always search the forums too:

Robbe Robivor M #5733 is your google search description. 

Edited January 10, 2019 by krow113