Brass, stainless, something else?

[shikeswithcanoe]

Hi all.

Working on a skin on frame kayak. At the bottom of each frame/bulkhead I want to epoxy in some nuts or short sections of threaded rod coupler. This will allow me to secure a floor and or foam floatation to the bottom at some later date if I so desire. If they arent being used, I just keep some temporary screws in place to keep grit, gunk, and moisture out.

Given that its very hard to get in there once the kayak is fully assembled, I want the stuff to last.

So, should I use brass or stainless steel or perhaps aluminum or something else I havent thought of?

 

[oldsparkey]

Out of all your choices I would use the Brass , it will cost more but it should be there forever.

Chuck.

 

[Kayak Jack]

Something to consider is a galvanic reaction. Two, dissimilar metals in the presence of an electrolyte (dirty water, in this case) make a battery. Electrolysis will remove parent metal. If you use brass nuts, then also use brass screws. Same thing with stainless steel. If you do select stainless steel, get GOOD stuff, not cheap stuff. I'd avoid aluminum; it may have little strength to resist threads being ripped out. And, it may corrode more rapidly than either brass or stainless steel.

BTW, this galvanic reaction can occur on metals simply from sanding them. The two, most common abrasives are aluminum oxide (ALOX) and carborundum. Don't use carborundum on aluminum parent metals, and don't use ALOX on ferrous metals. It will induce surface corrosion.

 

[tx river rat]

Brass all the way
Stainless threads have a habit of seizing unless you use an anti sieze lubricant.
Ron

 

[shikeswithcanoe]

Thanks guys. Lots of good input there.

Its brass then. And I'll make sure to use brass screws in there as well.

 

[Kayak Jack]

Its brass then. And I'll make sure to use brass screws in there as well.

... and if your boat needs any balls, ........ :wink:

 

[gbinga]

Or bronze if you can get it. Stronger than brass. Probably not a big deal for the application you are talking about, though.

GBinGA

 

[BEARS BUDDY]

Or bronze if you can get it. Stronger than brass. Probably not a big deal for the application you are talking about, though.

GBinGA

Marine bronze is best. Do not use brass if you ever intend to use the boat in salt water. All that polished "brass" on Navy ships is really manganese bronze.

 

[rpecot]

galvanic series

I found this prettty extensive list on the net. If you must have dissimilar metals in contact with one another, try to get them as close together on this chart as possible.