What Fasteners to Use With Aluminum Tubing

[DocHeb]

I'm starting to refurbish an old pontoon boat. The previous repairs were really makeshift, at best, and I'm stripping the deck back to the frame and replacing most of the top structures. The aluminum tubing that makes up the railings was fastened with plain zinc fasteners that had rusted severely.

I know that steel has some type of galvanic reaction when used to fasten aluminum. I'd like to replace the hardware that attaches the aluminum pieces together and to the deck. Would stainless steel fasteners cause problems?

 

[Chechnya]

tig welding

galvanized would be best

 

[Lou_B]

Stainless steel fasteners will work fine especially if you can keep things dry. Neither aluminum or stainless corrode very much by themselves so your boat's fittings should last a while.

There will always be some level of galvanic corrosion when two dissimilar metals are joined by an electrolyte (water in this case). The aluminum would be the sacrificial metal. Minimizing the action of the electrolyte is the key to success.

Lou Braun

 

[5030]

Docheb:

Try to seperate the dissimilar metals. Use a hard plastic spacer between the metals and coat your fastners with a marine dielectric paste.

 

[JohninCT]

Take a look at this site. They have clamp type fittings for aluminum railings.

Aluminum Railing Fittings

John

 

[Currmudgeon]

Those are sized for pipe, which generally has a different OD than tubing. But you can also get Aluminum pipe.

I'd look in McMaster Carr and Reid Tool for aluminum tubing setscrew fittings.

If you need enough of them, they will pay for the welder.

 

[chucko]

try asking some of the boating people like on www.thehulltruth.com

 

[DocHeb]

Thanks Chucko and everybody for your replies. TheHullTruth.com gave some interesting info - most recommended stainless steel and isolation washers. Most of their discussion threads involved saltwater exposures with aluminum boats, so I feel that my environment will be less corrosive. I ordered my SS hardware today from BoltDepot.com.

 

[chucko]

My boat is my other bad habbit

 

[JJJackson]

For fasteners made from Aluminum try this site.
http://www.aluminumfastener.com/