Bronze Cotter Pins

[Brian Duff]

So how come more people don't use bronze cotter pins?
I caught that piece on them in Brions' book, and it makes sense to me. Stainless cotter pins can be a pain to remove, and aslo break pretty easy from fatigue ( not supposed to reuse them anyway though.)
I have never used bronze pins so I can't compare. The other riggers in my shop were shocked by the idea of bronze pins, and said they wouldn't last long and mightn't be stong enough . I was taught that bronze clevis pins were a poor choice and told that was because of their lesser strength , but the cotter pins were never mentioned before to me. Were does one even get good bronze cotter pins from ?

Thanks for your input,
Brian

[Renoir]

Years ago I was advised by a very good prop and shaft "man" to use bronze cotter pins on my stainless prop shaft keeper nut. Always worked out well for the reason that you mentioned. I'm finding it more and more difficult to find them.

Since then I have used them as often as possible with stainless steel (and other bronze pieces of course) with excellent results. There never has been a problem with electrolysis betweent the apparently dissimilar metals and there is a good reason why. I placed many pieces of bronzes, like bushings, cotter pins, etc. in with 316 S/S and my local seawater. Using my DVM I measured the potential differerences between them. Many bronze alloys are quite compatible with the 316 S/S and others are not so much yet, even they are not too "far" out in terms of potential difference. That shows just why I have not had an electrolysis problem with the two metals.

Looking at the tensile strength of various bronzes it appears that some of the silicone and phosphor bronzes are not very much lower on the scale as compared to that of 316 stainless. After all, 316 stainless is not all that strong as far as steel goes.

Near the Brion Toss rigging shop there is a store which sells bronze hardware and I try to "fill up" with bronze cotter pieces whenever I am there. Perhaps Brion knows if they are accessible via the internet.

As an added benefit to using bronze with stainless, sometimes I use bronze nuts with stainless capscrews when I am concerned about potential gaulling with constant torqueing and removal. With the bronze nuts there is no gaulling.

[Jim Fulton]

Jamestown Distributors (http://www.jamestowndistributors.com/index.jsp) offers a good selection of bronze cotter pins.

Jim Fulton

[Bob Pingel]

I have been using bronze cotters the last few years, they have worked out great. Easy to install, easy to remove, no crevice corrosion.

I get mine from Jamestown Distributors, I think Fasco (www.fascofastener.com) sells them too...

Bob Pingel