Stainless Steel hardware for compass installation

I just picked up my order of stainless steel parts to install my deck compass. Low and behold, they are slightly attracted to a magnet! It turns out that some stainless metals are magnetic. See

I would think that this would matter with a deck compass, but by how much? And where can I get non-magnetic nuts, nylocks and washers? Home Depot isn’t the answer it seems. Or should I just go with what I have?

A single set of one bolt, 2 washers, and one nylock is enough to move the compass by about 2-3 degrees. But… when all four are in, shouldn’t they cancel each other out?

On the other hand, the 4 screws supplied are completely non-magnetic. I would just rather use bolts/nuts instead of sharp pointy screws.


The problem for accuracy would be that as the needles gets closer to the magnetic bolts/nuts/washers, it would deflect more, so you would have a reading that is foo in some places, and might be good in other places. I would think you could see this by setting the compass on a board, and installing the bolts/nuts/washers loosely, then rotating the board to see how the compass reads, comparing to say a separate compass held far enough away to not be affected. How much it matters depends upon how much accuracy you would like to have. I would get different fasteners, myself, but then I do not have a deck mounted compass, so you need to think about it for yourself.

You might try West Marine, they have quite a selection of SS fasteners.

McMaster sells Type 316 bolts at least… searching now.

Oooo, West Marine, yes, good call!

Yu can buy a deck compass with a plastic case that has bungees attached to it and secure it with hardware some distance away from the compass.

Thanks, but I already own the Brunton compass that fits in the deck receptacle.

Jamestown has Bronze fasteners as well as 316SS.

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sweet, thanks!

Favorite part of our local hardware is the “small drawers” section where you can find nylon nuts, bolts, and washers. Back in the day I zip tied a deck compass to my deck rigging and it worked quite well.