Oval exhaust tube experiments. Nascar boom tubes(Advice needed!)

[Jurva]

Couple of weeks ago, I saw this Dodge sporting nice oval shaped exhaust pipes. It got me thinkering, how can I make similar and realistic ones to scale models.

Since I wanted pipes to be pipes, I tried heating radio antenna, and making it oval shaped. Kinda easy process, but hard to make two similar ones. Also hard to make longer section. Also you have to make the transition to normal exhaust pipe size.

Of course, if you only need piping section to underneath the car, you can shape some round rod to oval rod.

Then I remembered, that I had made some experiments of exhaust tips before.

-Cutting round tube to half and widening it. Hard to make super smooth. I think this is the way Nascar boom tubes are made. Could be wrong.

-Pie cutting tube and making it pointing down.

-Using radio antenna with pipe bender. It has too small wall thickness, so it wants to crumble. If stopped at the right moment, it could be snapped into two pieces. I can create two identical ovalish shapes.

-Heated and drilled exhaust tip from parts sprue. Hard to make wall thickness realistic, and you could see the inside being not hollow.

There is also sometimes oval exhaust tips in kits.

I like to use real pipe on my exhausts, because it adds realism. It is also one of my favourite parts when modifying cars. I hate some of the kits, when exhaust is molded shut. You could drill those ends open, but I find it difficult. Centering the hole, getting wall thickness right. Those things. When the tips are not round, it gets even harder. Carving an oval hole. Not going to be clean.

Almost every time I change at least the round tips, to hollow ones. I like using radio antennas and electric wire crimps. You could even use crimps with the plastic things on, to have some interestign shapes. Crimps could also be used as intake funnels.

 

-What kind of methods have you used when building interesting exhaust pipes/tips/heatshieds?

-Have you tried to make Nascar boom tubes?

[peteski]

If you are looking for thin-wall metal tubing then you should check out hypodermic tubing.  It comes in couple of wall thicknesses (both very thin).  I get mine from http://www.componentsupplycompany.com/ 

Also Albion Alloys (in UK) sells thin-wall brass tubing which is softer than stainless steel hypodermic tubing.

If you looking for a cheap solution, some pen refills (like Parker) are made from thin metal tube.  I save them when they are out of ink for some possible model use.

To  prevent the tubing from collapsing while you flatten it, you could fill it with low-melting point metal alloy (that melts in hot water), form the tube, then put it in hot water to melt the metal out of it.

Edited August 18, 2021 by peteski

[Jurva]

Yes i have some Albion Alloys tubing. They're great. It's the shaping part that's hard. Could some kind of buck work? Has anybody tried? And has anybody tried some methods of filling the tube?

[Chariots of Fire]

Take some brass tubing, put in a vice and squeeze.  It'll come out pretty close to what you want.  Aluminum tubing would also work and you would not have to paint it.😎

[Jurva]

I used Albion Alloys brass tubing for these side pipes. Mainly because I can bend it, without it crushing. Although, I had to use smaller tube inside bigger, to get 90 degree angle. Secondly, they fit inside each other.

I also had to drill the tips, so the pipe wouldn't have too thick walls.

[Jurva]

On 8/26/2021 at 8:49 PM, Chariots of Fire said:

Take some brass tubing, put in a vice and squeeze.  It'll come out pretty close to what you want.  Aluminum tubing would also work and you would not have to paint it.😎

This method might work. There's two things that I can think would be issue. First, you have have something to protect the pipe in the vice. Otherwise you could have nasty marks in your pipe. Secondly, some kind of spacer or stopped would be required to make two identical oval tubes. Thirdly, what if you like a bend in your fresh oval tube. How do you make that? Also how to attach oval tube to reqular round exhaust pipe? I'm in for all kind of advices and tips. I like making custom exhausts to my models and I like to make them "realistic". At least the tips need to be hollow.

[Chariots of Fire]

You only need to flatten the end for a short distance.  Ok.  Put a piece of electrical tape on the jaws of the vice, assuming that they are not smooth to begin with.  Use a block of wood shaped to the thickness of the oval you want and put it inside the tube and squeeze.  Easy peasy!

[SfanGoch]

Brass and copper oval tubing is available from K & S and other suppliers. . No crimping or crushing required. Just cut the required length.