How do you bend stainless steel please

[Guest]

Managed to get some offcuts of 316 stainless
3mm thick.

They are only small - around 3"x12"

I would like to cut bits and bend at right angles to protect cockpit elbows against rubbing from jib sheets etc.

Would be very grateful for any suggestions.

Many Thanks

 

[ccscott49]

I hesitate to say, but with a great deal of difficulty is the answer to your question, I would put it in a vice, and just bend it with a mallet, you will not get a perfect 90deg corner, it will have a curve. Once bent, it will not bend back without breaking, it's stubborn stuff. 3mm isn't that thick, so you may manage without too much trouble.
However, I wouldn't use stainless if I were you for chafe protection anyway, I would use leather, if its wood, use copper tacks to hold it on, if glass, glue it on with two pack, contact adhesive. The stainless will damage your sheets, you could even consider putting "bullseyes" where needed to keep the sheets off the cockpit sides. IMHO, FWIW etc.

 

[Strathglass]

I have fitted stainless wear pads to protect the GRP corners on the yacht I am building.
3 mm can be bent fairly easily using a vice with hardwood pads and a heavy hammer.
It is much easier to use thinner material.

I made some of my pads from 1 mm stainless to protect the coachroof corner from the genoa control lines.
If you look at Boatone's Boating Gallery, photo 51 'Heater exhaust 1' you will see one of them.
You will find that a normal DIY 1/3 sheet sander will easily remove any 'machining' marks inflicted during your bending.

Iain

 

[Avocet]

It "work-hardens" a great deal - in other words, the more you deform it, the tougher it gets! Look very closely at the bits to see if they have a "grain". No, I haven't gone completely mad! As it goes through the rolling mill, it will have VERY faint stripes on it in the direction it was rolled. Obviously, if it has been polished, these will have been rubbed off but if it hasn't you might see very faint traces. If you can, fold it across the grain NOT along it. This will reduce the chance of it cracking as you fold it. As someone else has said, if you get it wrong, the chances of being able to straighten it out are almost zero. 3mm is very thick for anti-chafe. I doubt you'll be able to get an inside bend radius of much less than 3mm without the edges starting to crack (asuming it's a 90 degree bend).

 

[tr7v8]

Not only is it a pig to bend it's not the easiest stuff to drill either!
Best thing I found was Bullet drills from Black & Decker (sold at B & Q) and loads of lubricant, either Rotol or at a pinch WD40.

Jim
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[aztec]

easy answer... you don't!

what you do is go to your local sheet metal fabrication shop (you will have one nearby, most industrial estates have loads) walk in and talk to the bloke with the roll up hanging from his mouth (that's the important bit) tell him what you want, ask his advice (people like this) and pound to a pinch, he'll bend them in his lunch hour, for the price of a pint (providing he's not an alcoholic)

also fabrication come in handy for all sorts of jobs, welding stainless and aluminium is a similar process, so keep 'em sweet and it'll save you loads of coin.

regards, and good luck, steve.

 

[VMALLOWS]

I have not had any great problem dealing with stainless at 3mm .....and have managed it up to 5 or 6mm. As you say, it's brute force, but get it right first time.
As for drilling (other poster) you really must use a slow speed and lots of pressure. If you have a bench pillar drill, and use it well, you'll cut through it like butter. (Wish I'd had mine when I built the boat). Of course, your drills must be in perfect condition.

 

[BrianJ]

Vic. I went to a second hand dealer in SS and found all sorts of bits and pieces for my yacht..amazing what you pick up there . if there is one handy to you suggest you pop in before you try to bend SS
BrianJ

 

[tr7v8]

I've used this guy in the past for small bits of metal and in fact Nylon, alloys etc:-

Steve Taylor
Mail Order Metals
78 Colleymoor Leys Lane
Clifton
Nottingham
NG11 8JD +44 0115 974 8211

He works strange hours so leave a message.

JIm
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[c4pt]

Have a walk round a few of your local parks on a Sunday Afternoon. If there is a small "ride on" railway. Talk to the guys driving and running it. They will be all skilled engineers with a vast array of tools, Big drills, welders, lathes,saws, millers and grinders. If they don't know, or can't. They will know someone who can!
C4PT

 

[gus]

Drilling stainless steel is easy as long as your drills are sharp and you use firm steady pressure. I regrind my drills by hand and can drill stainless with no more trouble than drilling ordinary mild steel - and no lubricant. If your drills are blunt - forget it! All you do is work-harden the steel and give yourself earache.

 

[peterk]

vic,

if you just want it for chafe protection
trade someone for 1-1.5mm sheet stainless.
Much easier to bend (use alum. oder wood-protected vise-jaws and a mallet)
and to drill -
and plenty thick enough

...peter, www.juprowa.com/kittel

 

[brianrunyard]

Heat it up to bend it.
To drill, use sharp drill and keep a steady pressure, if you let the drill rub it will work harden the SS and ruin the drill bit.

Brian
http://homepage.ntlworld.com/brunyard

 

[Gunfleet]

If he heats stainless it up it'll go yellow, just like it does on motorcycle exhausts - or do you have a way of stopping that (not a trick question, I'd like to know(says ancient motorcyclist)

 

[Avocet]

I think you can polish it out with lots and lots of Solvol Autosol but it's VERY hard work! Rotary buffers are better if you can get the component off the boat!

 

[brianrunyard]

How do you think they do it in an engineering workshop?
They polish it. Use rotary polishing mops and buffing soap.

Brian
http://homepage.ntlworld.com/brunyard

 

[Gunfleet]

I didn't know. You'd be surprised how many operations in a machine shop are a mystery to me. Then again perhaps you wouldn't!

 

[Guest]

Just treat it like a toughish steel, it's very forgiving and knocks and scratches can be removed first with a file and then with emery. We work with it a lot.
If you need it machined call me.

Bernie

 

[Guest]

best bet is to find a local fabrication company they will have a press brake or folding machine. they will only charge a couple of quid if its a simple job.

 

[jameshenry]

For this purpose you have to take the help of proper instruments. Still if it is not possible then you have to visit some professional dealing on the subject.