Freezing expansion chamber?

**Rupe** · 24th February 2008, 19:53

Has anyone done this to remove dents? Does it really work, and anyone got any tips?

**Quicker_with_age** · 24th February 2008, 20:39

Had a small amount of experience with using compressed air and heat to remove a large dent but thats all, Never tried the ice thing but i guess it could possibly work also.

**scott411** · 24th February 2008, 20:47

we haev always used compressed air and heat, i have heard of freezing water in thier as well, never tried it, but have heard some people swear buy it,

**Rupe** · 24th February 2008, 20:49

Originally Posted by scott411

we haev always used compressed air and heat, i have heard of freezing water in thier as well, never tried it, but have heard some people swear buy it,

Could you explain how you do it with, compressed air, and heat???

How do you seal the pipe etc

**Subike** · 24th February 2008, 20:55

put your thumb over one end, put the othere in your mouth and blow really hard!

Na! really! true, I kid you not , it works!

You can buy expanding rubber plugs of differing daiameters that can lock into the "large" end of you pipe,They have an internal scew that expands the rubber up to 10mm larger than its origional size
and you can , using the same type of plug , easily make one with a tyre valve fitting in it. Heat the pipe, turn on the compressor
The rest is simple common sense

**dereka** · 24th February 2008, 21:17

Yep I have tried it and worked really well.

I had a header pipe that I was going to throw out then heard about using the water and freeze method.
Just filled the pipe so the water was in the dent area (dent was in the curve where it comes around the engine) and put it in the freezer.
Pulled it out the next morning and then dent had came out a bit. So did the exercise a couple of more times and almost perfect result. You would have to look closely to see where the dent was.
I was pretty sceptical but would have to say it worked perfectly.

Be careful when the dent is almost out because you run the risk of splitting the pipe.

Good luck.

**Grub** · 24th February 2008, 21:37

Originally Posted by dereka

Be careful when the dent is almost out because you run the risk of splitting the pipe.

And be careful when you put the dirty pipe in the missus's nice clean freezer because you run the risk of a splitting headache

**old git** · 24th February 2008, 21:43

just leave it, it will add character........., then when you get another you wont care at all!!!

**B0000M** · 24th February 2008, 22:48

done the freezing thing myself, works a treat. wrap it in a old towel to avoid the above mentioned headache

**camchain** · 17th May 2008, 00:18

I've heard that you have to watch the freezer trick on expansion chambers - it can split on the seams. Probably has something to do with greater volume = more expansion as ice expands your expansion chamber. (I could expand on this but i better not)

**camchain** · 17th May 2008, 00:19

Somehow ended double posting this?? can't remove

**The Pastor** · 17th May 2008, 00:37

Yeah you have to be careful that its just the dent you want to remove, other bits might get out of shape.

**T.W.R** · 17th May 2008, 09:56

Originally Posted by Quicker_with_age

Had a small amount of experience with using compressed air and heat to remove a large dent but thats all, Never tried the ice thing but i guess it could possibly work also.

Originally Posted by scott411

we haev always used compressed air and heat, i have heard of freezing water in thier as well, never tried it, but have heard some people swear buy it,

Water & freezing are a lot safer than heat & air trick though a lot slower

tack welding a rod onto the dent and applying heat then pulling the dent works, or drilling a hole into the opposite side the pipe and along with heat to the dent push it out from the inside with a peen punch.

any option is going to leave creases in the pipe surface; and if a seam lets go it's easy enough to weld up again & no worse than cutting a pipe open to decoke it

P.S: Works a lot better on thin wall titanium pipes rather than stainless or standard steel chambers

**4stroke** · 17th May 2008, 15:14

can you shrink it like a big steel plate, heat the dent up glowing then quench it (dunk it in cold water) shrink the dent out?

**Reckless** · 17th May 2008, 16:15

Watch doing that 4Stroke that will temper the steel and make it hard and therefore brittle. I wouldn't use that method, you'll end up with more problems than you started with I.E. a stress crack after the pipe has been heated and cooled by the engine over the next 12 months.
All the other methods make sense though. Thats if 10 years panelbeating give me any experiance!