DIY Stainless backrest etc

slimtim · 22 February 2005, 16:45

I have just discovered (after nearly 4 years at uni) that there is a student workshop here at southampton with lathes and wotnot in it. Apparently there is also a pipe bender and I think its one of those hand held jobbies.

For my project boat, I want to make (so its cheap, like a budgie) a stainless backrest and maybe a few other bits.

So my questions are:

1. What diameter and tube thickness will I need for a backrest? I understand it is 316 stainless, is this right?

2. Where is a good (cheap as possible!) place to purchase this SS tube and what kind of price am I looking at? I found somewhere that had a 3m length for around £15...is this about right?

3. Will the tube flatten and crack when bent in a regular pipe bender? If yes then can I pack the tube with sand and then do it successfully?

4. Any tips or other advice/brainy ideas?

Thanks in advance for the help.

Cheers

Tim

danny · 22 February 2005, 17:37

Ok slimtim.

Overhere we pay about 7 euro p/meter for 22 mm pipe when it's 2 mm thick and allready high polished.
So I think that your price is good.
When you use a bender, try to use the specific bender for this kind of work. It has a 180 degree fitting (half the pipe coverage) and the moving part on the bender must also be the same. In that way your pipe will be closed up when bended. Don't use a regular bender. This will not give the result you want.
Always use 316 inox especialy when your boat is used in salt water.
When you want to weld it, only use a TIG machine with Argongas. This will give the result that you see with proffensionals.
When welded, use weldpaste (i don't know the english name, it's like an acidpaste to bring the chrome and nickel up to the surface)
Then Polish the piece.

Preparation is half the work, Good luck.

Dan

slimtim · 22 February 2005, 17:50

Thanks for the info Dan. I'm not overly familier with pipe benders so don't really know what you mean. Has anyone got a picture of the bender I need? I will have to make do with what I have available.

There is a welder here who is good at SS welding so I will ask him to do that. I could do welds instead of bending but he might start charging me if I ask him to do too much!

Cheers

Tim

Hightower · 22 February 2005, 18:11

Tim, phone Carisbrooke at Fareham, they will supply you with 1"/25mm SS tube of any length at £4/m. Tell em its for a back rest just to make doubly sure that you get the right stuff. You can also purchase some SS plate to make the mounting brakets up.

Right, when you bend the tube it will flatten and distort if you don't use a 50/50 former with the bender. The former on one side will be attatched to the main body and the other side will be on the "moving" handle side. Might be prudent to ask if you pick up your tube from Carisbrookes how much to bend your tubing. Shouldn't be much. Be shure to leave the legs longer than you need, just to make sure it looks good when you get back to your boat.

Andy

Hightower · 22 February 2005, 18:21

PS, I'd have offered you to redeem your voucher Tim, but the bender at work isn't terrific and my welding skills leave alot to be desired

. See my backrest in a couple of weeks time.

jwalker · 22 February 2005, 19:17

If the bender is the type generally used for bending conduit or plumbing pipe, you may find it is hardly up to the task. If it's free standing, you'll probably need to hold down the foot and use a long piece of tube (scaffolding or similar) to increase the leverage. It might be possible to break it! If it's a bench type, be sure it's firmly attached to the bench and the bench is firmly attached to something. If it's a hydraulic bender you're in with a better chance. For a mechanical bender, the roller, ideally, needs to bear on a former which has the correct inside radius for the tube and the outside is flat. A roller which, itself, has the radius machined into it is not so clever. Even a cylindrical rolled can be used but it gives a flat outside edge. It makes the tube section 'D' shaped around the curve but if the equipment is lightweight, it does reduce the load because the outer surface doesn't need to stretch as much. Ideally, you need a proper hydraulic bender which is capable of the job. But if need must, where there's will, there's a way. Yep, even dry sand, a couple of bungs and some heat can be made to do the job. Stainless is fkin tough though.

SOLENTER · 22 February 2005, 19:31

Tim
I T S Tools hire hydraulic tube benders they give you better control
& a better job

slimtim · 22 February 2005, 19:57

Thanks for the replies guys.

I believe it is a handheld bender and more than likely, its a load of crap. I have heard there may be a hydraulic one about, but I probably won't be able to use it and it might cost me to pay someone who can. I may be able to wangle it though

Grumpy, I like the idea, although I may as well pay someone to make me one than pay to hire a machien to make my own (and probably mes sit up!)

Cheers

Tim

cliffy · 22 February 2005, 21:00

Hi good luck!! you will not do it with hand held.
I am not just say that because I can sell you some.
But all the same if you get stuck £130 a pair.

Pete7 · 22 February 2005, 21:10

Tim, take a walk down Burseldon scrap yard, loads of pushpits and pull pits in 1 inch stainless off old yachts, your bound to find something nearly right.

Pete

Hightower · 22 February 2005, 23:38

Tim, if you can wait a couple of weeks you can see my backrest. It's not a bad effort, just wait and see! If you like the bend radius I could have a go at work if you like.

Andy

slimtim · 23 February 2005, 08:25

Pete, Still got to find some time to get down to the scapyard!

Andy, yes I can wait a couple of weeks as once again I'm snowed under with project work so won't be able to make anything for a while.

I'm going to have a word with the guy in the workshop in a minute to ask about the bender.

Keep the advice coming!

Cheers

Tim