I am building an Aluminum Sailboat with a spade rudder and rudder stock. I am planning to use UHMWPE plain bearings. Would it be a good idea to hard anodise the shaft in the area of the bearings to reduce the wear? Would there be any corrosion issues? Thanks, Howard
Hi Howard: There are several issues at play. First is the alloy of the rudder stock. If this is 6061 or 6063, it would be best to anodize because of long-term corrosion under water. 5083/6 is not so sensitive and you can get away with using it bare (it is also stronger).
As to wear, while the anodized surface is indeed harder, both alloys will wear on the UHMW before the aluminum sheds material.
Bottom line–if you can anodize without busting the budget, I would do so.