Tube bending and... custard

[Mr Fro]

I had a thought the other morning - instead of packing a tube with sand or freezing it full of water to prevent deformation, would it be possible to pour in some non-Newtonian fluid e.g. corn flour?

Theoretically, it'd pour in nicely, firm up during bending then pour out again - it'd be ideal for complex bends and things that won't fit in the freezer.

I'll give it a go during the week with some copper pipe but until then, has anyone got any thoughts or seen a product that does the same thing?

Cheers,
Fro

 

[Shox Dr]

Yes it's called. WS8 and nots not cheap, search the forums. I've posted on it before

 

[BrokenBiker]

Place where I did my welding course used to use some form of thick sludge when bending thin wall stainless tube for handrails and so on. No idea what it was but it was the consistency of a cv grease

 

[ibrooks]

I can't see cornflour working - it only seems to "go non-Newtonian" when you try to make it flow quite quickly. Unless your bending process is fairly rapid in it's motion I'd imagine cornflour wouldn't make much if any difference.

Thinking about it - is it really a non-Newtonian fluid that you want for the job? wouldn't something thixotropic be more suitable?

 

[BrokenBiker]

I can't see cornflour working - it only seems to "go non-Newtonian" when you try to make it flow quite quickly. Unless your bending process is fairly rapid in it's motion I'd imagine cornflour wouldn't make much if any difference.

Thinking about it - is it really a non-Newtonian fluid that you want for the job? wouldn't something thixotropic be more suitable?

non newtonian fluids only firm up under percussive action so i dont think bending would give the required effect, as i say the company i have seen using a fluid filler used some thick grease like stuff, just filled it in then bent the tube, got most of it out with a flexible rod then washed the rest out and blew out with an air line

 

[lchris21]

Google "woods metal" or preferably a non toxic variant. I well renowned motorcycle frame builder I was chatting to a few years back used this in his lightweight frames. Melts at about 80deg??? I don't where you'd get some??? Think most of it and its equivalents are pretty nasty stuff???

 

[Seadog]

Google "woods metal" or preferably a non toxic variant. I well renowned motorcycle frame builder I was chatting to a few years back used this in his lightweight frames. Melts at about 80deg??? I don't where you'd get some??? Think most of it and its equivalents are pretty nasty stuff???

Like most things, you can buy it on eBay.

 

[Mr Fro]

Woods metal sounds interesting.

I think it's worth an experiment although I think you're probably right BB - it'd have to be a pretty quick bend for it to firm up sufficiently to prevent deformation.

 

[Kent]

Like most things, you can buy it on eBay.

The nice man from the government say you just can't buy plutonium on the Internet

Quote from
Sheldon coopers mum

 

[500e]

Just love mother

 

[Cobbler]

The nice man from the government say you just can't buy plutonium on the Internet

Quote from
Sheldon coopers mum

I bet Maker would know where to get it, he seems to be able to find most things.