Stainless and Aluminum

[Uncle Dave]

Is there a long term problem with using stainless screws and nut to replace alum rivits in an aluminum hull. Particular for use in saltwater?

 

[walleyehed]

Re: Stainless and Aluminum

aluminum will be better than the stainless bolts because of intergranular corrosion-2 dissimular metals in direct contact. stainless bolts are also very brittle. I assume you will be painting this??? if so, zinc chromate, or 2-part corlar dupont epoxy primer is best before Paint.

 

[Uncle Dave]

Re: Stainless and Aluminum

They will be painted (inside the hull) with aluthane and then a coating of flex3 which is similiar to bedliner.<br />The screws will be "treated" with 3m 5200 prior to instalation. Then epoxy paint to match the outside hull paint which is 95% good at present. So the plan is for no water to ever reach the dissimmiliar metals.<br />Mr.F.

 

[ratt1966]

Re: Stainless and Aluminum

even tough you are making the boat where water can not get to the bolts the stainless and aluminun will react to each other causing corrosion which could let them com loose I have worked in places that had aluminun bolts and nut here is a site that might help<br />www.aluminummetal.com <br />www.mcmaster.com/ also try here type in aluminun machine bolt

 

[jimchere]

Re: Stainless and Aluminum

Use Aluminum. If you use stainless steel, in saltwater as said above the two dissimalir metals will galvanically corrode. In this case, your aluminum boat hull will erode away to the stainless.