Stainles v aluminium

[JSP]

The mount bolt for my engine go through the transom and then through 2 box sections, one on the top 2 bolts and one across the bottom 2.
I was going to do away with the box sections and just put a large stainless plate across all for bolts but I've decided to stick with the box section.
The box section that's on there now is only mild steel and needs replacing.............So which is best, Stainless Steel or Aluminium box section. Aluminium will be the lightest but at this kind of size it doesn't really matter.

And does anyone know of a good retailer? Or anyone got some laying around somewhere and want to do JSP a favour

[jyasaki]

If the section is supposed to provide stiffness for the motor mount, I'd go stainless. It can be thinner than aluminum for the strength, so the weight tradeoff isn't as great as you'd think.

jky

[Leapy]

Originally Posted by jyasaki

I'd go stainless...

Agreed. Strength for strength aluminium is about 30% lighter but over the sort of size your talking about not worth the trip

[martini]

I've got 2 stainless plates 8mm thick drilled for the same purpose, nothing fancy as they were only a temporary measure. I was going to hang on to them in case they came in handy 1 day but I may let you have them if you really wanted them. I think they are 100mm wide but not sure.

[JSP]

Thanks for the replies lads

Originally Posted by martini

I've got 2 stainless plates 8mm thick drilled for the same purpose, nothing fancy as they were only a temporary measure. I was going to hang on to them in case they came in handy 1 day but I may let you have them if you really wanted them. I think they are 100mm wide but not sure.

Martini,
that's very kind of you but I have already bought the bolts to fit. Thanks anyway Arse about tit way of doing it I know but saw them and bought them. Got 316 A4 M12 bolts as you recommended

[JSP]

Only stainless box section I can find is in 304. Would that be ok for the job? Sorry I know sweet f-all about this kind of thing.

[martini]

Originally Posted by JSP

Only stainless box section I can find is in 304. Would that be ok for the job? Sorry I know sweet f-all about this kind of thing.

I don't think it's really commercially available in 316. 304 won't exactly corrode but it will stain and probably leave brown streaks down the inside of your transom

[JSP]

Originally Posted by martini

I don't think it's really commercially available in 316. 304 won't exactly corrode but it will stain and probably leave brown streaks down the inside of your transom

Balls!
You know ya stuff mate, as far as strength, for this kind of application any way, would box section offer me that much more strength than a thick plate of stainless?

[jyasaki]

Originally Posted by JSP

Only stainless box section I can find is in 304. Would that be ok for the job? Sorry I know sweet f-all about this kind of thing.

http://www.onlinemetals.com/stainlessguide.cfm

jky

[martini]

Originally Posted by JSP

Balls!
You know ya stuff mate, as far as strength, for this kind of application any way, would box section offer me that much more strength than a thick plate of stainless?

None whatsoever!