Strength of Brass bolts

[dmr]

Have just had to remove a mushroom vent and bullseye to do some derusting. The fixing screws (m5 countersunk machine screws rather than bolts ) were very very tight and a few sheared off, but it took a LOT of effort to shear them. My experience is that brass shears quite easily, and these bolts were a bit more brown/dark gold than the modern yellow brass. So what are they? Was brass much better and harder 20 years ago before we got Chinese yellow brass? or are they bronze? I can find a few people selling imperial bronze but no metric. Where can I get some nice strong brass machine screws?   I have tried stainless countersunk socket heads and they work great and will do, but don't look quite as good as brass.

 

..............Dave

[OldGoat]

IME proper brass (which you probably can't get nowadays) shears and strips, almost just by looking at it - certainly for the modern stuff. 

For anything remotely 'mechanical' I use SS fixings - but then my boat is to use and not polish...

 

Sorry.

 

I DO take my hat off and dip my Ensign to those who chose to keep their boat immaculate.

Perhaps I've been boating for too long....

 

No disrespec'

[BEngo]

Try Allfix for decent quality brass fasteners. They supplied my order of a mix of Imperial and Metric fasteners last time Jarrah was painted.  None have failed yet. 

N

 

[jonathanA]

You can get countersink Allen socket machine screws which I find perfectly acceptable. 

[Machpoint005]

Well, I don't know. The number of times I've walked past a boat and seen the stainless steel machine screws holding the "yellow metal" mushroom bases in place. Some people have no pride.

 

Most of us (1) mind our own business, (2) couldn't care less anyway, (3) didn't notice in the first place.

 

 

[DandV]

If they took a lot of strength to shear they may well have been bronze not brass. 

Stainless 316 had largely replaced bronze as a lower cost and as a stronger  alternative in nearly all marine applications which has meant bronze fastenings and fittings are now  really hard to come by.

We have to get  our bronze cleats especially  cast for our heritage yacht.   

Edited August 20, 2019 by DandV