The cast iron CB on my M17 uses white nylon bushings for the pivot pin hole. A modification made upstream from me by someone else. Thomas I suspect. I then use a stainless steel bolt for the pivot pin. These nylon bushings have a 1" diameter, 3/8" hole and are 3/8" thick, so two of them side by side span the width of the CB. The one I have in my hand cost 48 cents. If you needed a bigger pin, you could drill out the hole in the nylon bushing to make it larger. 1/2" should not be a problem. You could also make your own out of a block of Teflon or HDPE. For a HUGE pivot pin, epoxy in a short bushing made of PVC pipe. I think you are on the right track by avoiding dissimilar metals. On Dec 6, 2010, at 6:12 AM, robbin roddewig wrote:
First I appreciate all the great responses I got on the trailer rebuild. Lots of really good ideas which will make it very easy (in theory, until I try to remove rusted parts) for me to replace the whole drum brakes system on the old trailer without spending a wad of cash. Second, sorry for so many posts but I have another question that I am pretty sure the collective knowledge of the group could help with. I am about to epoxy a couple of brass bushings into my centerboard to replace the fiberglass bushing that I ground out of the pivot hole. When it occurred to me that I should consider whether I would have any issues with dissimilar metals since the centerboard sits in water (dielectric). I should know more about this but my engineering has kept me clear of battery chemistry and such and the only thing I found online is that I probably should not put a (Silicon) Bronze pin through my Brass bushings. So my question is given I have the freedom to put in what ever pin I want (from Duckworks) and can get some more bushings for $10-15 from McMaster Carr easy what would be a good combo of materials? I am assuming I can isolate the steel of the board and the bushings with the barrier coat and epoxy that the bushings will be put in with, so the issue would be the bushings and the pin.
Thanks Robbin
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