[choc-ice]

For a project I'm working on, I need to get a rollover bar and a bull bar, both with spotlights mounted on them. I think the section would be too narrow as a resin casting because it would snap when the car rolls over (ironic that the roll bar is the weakest thing on the car) or the bull bar would break after a light crash. I could possibly make up the parts from 1mm brass or aluminium bar, but then the spotlights will just break.

Could they be cast in rubber so they squash when the car rolls over? Is there another way?

 

[Julian_Boolean]

You can make roll bars out of metal wire.

 

[Mr Modifier]

Piano Wire is available up to 1.175mm thick - probably a little thin for 1:32 roll bars. You might find some copper wire from heavy industrial electrical cable and copper would be easier to bend.

To make the wire thicker and to make finishing it dead easy - can I suggest heat-shrink tubing? It comes in various colours and diameters so once you have made your roll bars you could heat shrink on your colour of choice.

As for spots - if you have the means to make castings then a high shore rating urethane rubber might be good although it would be difficult to paint. You can get pigment to colour urethane rubber, it's just a matter of economics really.

As for fixing the spotlights - if you use a material for your roll bars that is solderable you could add thin spikes on which you could push-fit the spotlights.

 

[Ember]

Wanting spotlights for a similar but unrelated project myself. Of coruse, I'd like them to be working ones.

The roll bar and bull bar could be made with wire, as suggested above, or brass or styrene tube.

 

[Nuvolare]

Hi,

I would make everything out of hard brass, I don't know if you are aware of it, but brass comes in different strengths, you got soft brass and hard brass. It all depends on what metals are used for the alloy. I guess there are better experts than me explaining about alloys. But it comes down to this, soft brass bents how you want without doing anything to it but it stays soft. Hard brass on the other hand breaks while you bend it. And you have to head it up, only then can you bend it into the shape you want. So if you make everything out of hard brass, you have to really through it, to break something off, and it will probably be the tin joints in between that will give away in first place. So it's really important that you solder it well with tin and not glue it with tin, as my father use to say. With glue I mean, when you don't heat the tin enough and it does not bond proper with the brass.

Cheers,
Danny

 

[choc-ice]

Thanks for the ideas so far, but I'm still wondering if the spotlights will break when it rolls over. You can see how vulnerable they are up so high

QUOTE (Ember @ 18 Mar 2012, 21:02) <{POST_SNAPBACK}>Wanting spotlights for a similar but unrelated project myself. Of coruse, I'd like them to be working ones.
Troublemaker!

Luckily mine only need to be painted, or perhaps even have a decal on them to represent the spotlight covers.

Maybe making the whole roll bar and spotlights in one piece as rubber so it bends lower than the roofline in a crash?

 

[Black3sr]

Spotlights -

I have used pushpins with small round plastic heads for mirrors after filing one side flat. If you can find some larger ones they would make soso spotlights?

 

[distantkiwi]

I take it the part can be 3d printed?

here is a place all about rubber molding.

There is this stuff that you can add metal powder(whatever that is) to the rubber to get a metalic finish.

 

[dangermouse]

what about a roll bar for the spotlights like on the scx hummer

though you could just bend two bits of wire around each light

DM

 

[MAF]

As per your 3d model they would be very vulnerable on those thin stalks, but if the spots are mounted directly to the roll bar there would be a much larger contact point and wouldn’t break off. I would use styrene tubing and styrene for the lights then 'weld' them together with liquid poly, that should take some hammering.