tube bending

[gary jackson]

anyone ever tried putting solid wire inside plastic tubing when heating to bend for rollcage. i thought it might keep the tubing from collapsing. i dont care if i have to leave the wire inside

[stitchdup]

It should work and if you did need to remove the material you could use sand inside the tubes

[Plowboy]

A lot of builders do it that way and it seems to work.

I use solid rod for roll cages, exhaust and headers. I don't have to worry about it collapsing or breaking.

[TarheelRick]

Floral wire works pretty well, however there is still the possibility the tubing will crack across the outside of the bend.  Like Plowboy said, solid rod seems to work better for me.

[NOBLNG]

It does bend nice with wire inside, but if you touch the bend with solvent glue, the tubing will instantly crack.

 

[espo]

I have done a couple of exhaust systems using hollow plastic tubing and a length of brass rod inside to hold the shape when bent. You may still have problems depending on how tight of a turn you want such as making a roll bar setup. A hard 90 degree bend is pretty hard to do with out the plastic starting to crack and even break open on a real tight bend. Gentile bends seem to work just fine, but remember the brass rod can't be removed after bending. I have seen plastic rod that already has a rod inside but I think you would have the same problem depending on how tight of a bend you're trying to make. My suggestion would be to experiment with a solid plastic rod and use some light local heating to make your bends. A jig of you roll bar setup might be a good idea and remember when heating plastic there seems to be a very fine point of getting it hot enough to bend and not so hot that it starts to melt or even catch on fire. 

[gary jackson]

cant seem to find 3/32 rod online   is there another size that would work for rollcage

[Ace-Garageguy]

11 minutes ago, gary jackson said:

... is there another size that would work for rollcage

What scale are you working in?

What kind of car (drag racing, road racing, etc.) ? 

What era?

[Plowboy]

41 minutes ago, gary jackson said:

cant seem to find 3/32 rod online   is there another size that would work for rollcage

I use .080 for roll cages. 

[NOBLNG]

.080” (x25) is 2” diameter in 1/25th scale or 1.92” diameter in 1/24th scale.

.100” is 2-1/2” diameter in 1/25th and 2.4” diameter in 1/24th. 
.080” is likely better, but either size would work. 3/32” is right in between them and probably only available as tubing.

Edited July 9, 2022 by NOBLNG

[gary jackson]

5 hours ago, Ace-Garageguy said:

What scale are you working in?

What kind of car (drag racing, road racing, etc.) ? 

What era?

1/25

[Ace-Garageguy]

57 minutes ago, gary jackson said:

1/25

Cages and bars these days are usually 1 5/8"or 1 3/4", depending on class and speed.

1 3/4" is 1.75". Divided by 25, that gives you .070".

I notice the difference using .080", but it looks pretty good usually...and is usually what I use too.

But I think anything bigger looks wrong.