I had forgotten that, so no great rush in dealing with the stud issue to save a few bucks.
Good. You've got three months to deal with the stud issue before your fingers freeze solid and fall off
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Keel stud chemistry
- Thread starter degas
- Start date
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Potential Values (Anodic Index)
If you want to take the most conservative approach, I'd use a more active stainless steel bolt and washer combination, then apply dielectric grease generously to help electrically isolate the stainless steel from the cast iron. Something like this dielectric grease would work well.
This may also be more precaution than necessity, but you could add re-greasing the keel bolts to your annual haul-out maintenance routine.
- Cast Iron: ~-0.69 V (more anodic/active)
- Stainless Steel (Passive 304/316): ~-0.05 to -0.08 V (more cathodic/noble)
- Stainless Steel (Active): ~-0.56 to -0.58 V (much closer to cast iron, with a potential difference of only about 0.11 V)
If you want to take the most conservative approach, I'd use a more active stainless steel bolt and washer combination, then apply dielectric grease generously to help electrically isolate the stainless steel from the cast iron. Something like this dielectric grease would work well.
This may also be more precaution than necessity, but you could add re-greasing the keel bolts to your annual haul-out maintenance routine.
......................... until somehow, someway, in some undetermined fashion, water enters the threaded hole(s) in the CI keel. Actually, the use of butyl rubber tape as a sealant under the nuts and washers might not be a bad idea when replacing the studs. This recognizes the fact that the galvanized washer isn't worth the powder to blow it to hell as far as cathodic protection goes.
To simplify matters here, I think the OP should restrict his sailing to the sands of the Sahara, or simlar regions, and eliminate the water intrusion problem at the source
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