what stainless steel for marine apps and how to work it.

M

MarkGrubb

Well-Known Member
Joined
28 Nov 2006
Messages
304
Location
Nottingham
Visit site
Hi,

I'm buying some stainless steel from metals on the web to make up a pair of L shaped brackts for mounting my Taylors cooker: an Ideal-K which is also stainless steel.

I'm not familiar with the different properties or finishes. Can anyone advise on what I should use for the marine environment: 304 or 316 grade.

Also the different finishes: unpolished, dull polished or bright annealed. Presumerably I would want dull polished or bright annealed, but I don't know what they look like. Is a Taylors cooker dull polished or bright annealed? Looks pretty shiney to me, so I'm assuming it's bright annealed, but please correct me if I'm wrong.

What is the best way to work with 2-3mm sheet stainless steel. I'm assuming I can cut it with either a hack saw or fine cutting wheel on the angle grinder, and then tidy up with coarse and fine files.

What about putting a bend in it. I have a beefy gas torch which can be used for metal work and the instructions explain that I should clamp the metal and then heat along the bend line before applying steady pressure to bend the metal. I want to put a 90 degree bend in to form an L shape. Will this work for stainless steel say 2 or 3mm thick.

If it all works, I may try making other fittings.

Advice and comments appreciated.

Thanks,

Mark.
 
316 is the usual grade for marine use.
If you are going to bend it I suggest you buy it "bright annealed".
I recently bent some 3mm stainless, about 30mm wide to a fairly sharp 90 degree bend using a small metal bender, followed by some work with a hammer. (Finished article here. )

2mm stainless is much easier to bend, and I doubt you need 3mm just to make brackets for a cooker. 1.6mm would probably be quite strong enough.

As for cutting it, I suggest you get a thin disk specially made for cutting stainless steel, using a small angle grinder. A few months back Lidl sold packs of 1mm thick stainless cutting disks, but any good tool dealer will have thin metal cutting disks but not always the special ones for stainless. A hacksaw will do it, but you will need fine tooth all hard blades, and it will be pretty slow going.

If you need to polish the finished articles, the only good way to do it is with a polishing mop and compound on a bench grinder, or better still a purpose built polisher, because most bench grinders are too low powered for efficient polishing.
 
I've just fitted one of these - you might be interested in this page .
I didn't use the gimbals, but made up some clips from fairly thin (0.5mm) 316 bright annealed - they locate on the base of the cooker, sticking out about 15mm with a self-tapper through the shelf on which it stands. The clips raise the cooker up by about 2mm, just enough to make sure that the copper pipes leading to the burners don't rub on the shelf.
I'm nowhere near the boat at the moment, but if you test your cooker with a magnet you may be able to tell if it's 316 (non-magnetic) or 304 (magnetic), but it may be another type of stainless altogether.
Generally speaking, use slow speeds and moderately high feed pressures when machine working stainless, along with a cutting lubricant (any sort of oil will do). Angle grinders are ok but the wear rate is high and the cut metal can reach astonishingly high temperatures so mind your fingers.
 
all the above but stainless work hardens very quickly, and normal hss steel drils and hacksaw blades very quickly go blunt. I use cobalt steel drills and blades which work very well with ss. again keep hte drills sharp, slow speeds with high pressure, once it starts to cut don't stop or i will work harden and youll be sharpening even cobalt bits every 5 minutes.
 
And dont touch it with and mild steel or a wire brush and cover vice jaws in copper or ally and dont file it,linish it with emery disks or it will start to rust.
 
You must log in or register to reply here.

Share this page

Top