RV News RVBusiness 2021 Top 10 RVs of the Year, plus 56 additional debuts and must-see units → ×


Reply
 
Thread Tools Display Modes
 
Old 11-05-2020, 07:14 PM   #1
Mini-Skoolie
 
Join Date: Aug 2020
Posts: 17
Floor patches / fasteners with dissimilar metals

I've been reading a bunch about this but wasn't sure if there's been a consensus just how bad is it if I'm using aluminum materials to patch my steel floor? Specifically:

1. The screws that kept the plywood on also attached the floor to the frame. To replace them, can I use aluminum rivets (possibly with a bead of silicone caulking)?

2. If I wanted to make some small patches, could I repurpose the aluminum side panels I yanked off during demo? Thinking about 2" x 2" glued with silicone.

3. I've read the penny/epoxy method is disputed because of this / galvanic corrosion in general. What do you think?

For context, I'm thinking of what condition the bus might be in 5 years from now. How quickly will these things become a problem?
r0meboards is offline   Reply With Quote
Old 11-05-2020, 07:34 PM   #2
Bus Geek
 
musigenesis's Avatar
 
Join Date: Jan 2019
Location: Philadelphia
Posts: 4,571
Year: 2003
Coachwork: International
Chassis: CE 300
Engine: DT466e
Rated Cap: 65C-43A
Metal will only corrode in the presence of water and oxygen. Just sticking two dissimilar metals together will not cause corrosion - it will only make one metal corrode preferentially if (and only if) corrosion is occurring at all. If the things you are attaching (patches, pennies, whatever) are completely sealed and painted, you will not have any corrosion, galvanic or otherwise. If your patches and hole covers are not completely sealed, then they'll rust anyway even if everything is mild steel (especially if everything is mild steel).
__________________
Rusty 87 build thread
musigenesis is offline   Reply With Quote
Old 11-06-2020, 11:04 AM   #3
Mini-Skoolie
 
Join Date: Aug 2020
Posts: 17
Quote:
Originally Posted by musigenesis View Post
Metal will only corrode in the presence of water and oxygen. Just sticking two dissimilar metals together will not cause corrosion - it will only make one metal corrode preferentially if (and only if) corrosion is occurring at all. If the things you are attaching (patches, pennies, whatever) are completely sealed and painted, you will not have any corrosion, galvanic or otherwise. If your patches and hole covers are not completely sealed, then they'll rust anyway even if everything is mild steel (especially if everything is mild steel).
Thanks for the response! I've been going off this article I found: https://www.trailer-bodybuilders.com...similar-metals

They say there that "If aluminum and stainless steel were immersed in a corrosive environment (road salt solution) the corrosive rate of the aluminum would be highly accelerated while the rate of the stainless steel would be reduced." which similar to your response, would lead me to conclude that an aluminum patch might be risky. So would covering the patch in primer/paint beforehand negate this?
r0meboards is offline   Reply With Quote
Old 11-11-2020, 09:05 PM   #4
Mini-Skoolie
 
Join Date: Oct 2020
Posts: 27
Year: 2008
Coachwork: Bluebird
Chassis: Bluebird
Engine: Cummins ISB
My experience

Here is my experience with steel and aluminum. I have a Datsun 280z of 1975 vintage. Rear brake drums are cast aluminum with a steel braking surface. The hub is steel. The aluminum drum is in direct contact with the steel hub. A new set of drums is pretty expensive. An original factory set of Datsun drums are like the holy grail, and nearly non-existent. Why you might ask, because the steel and the aluminum stick together so tightly, in many cases cast aluminum drums break trying to get them off. I dont think in your application putting steel and aluminum together is going to be that big an issue, as I doubt you plan to remove it once it is there.
Bpike is offline   Reply With Quote
Reply

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off


» Featured Campgrounds

Reviews provided by

Powered by vBadvanced CMPS v3.2.3

All times are GMT -5. The time now is 01:11 PM.


Powered by vBulletin® Version 3.8.8 Beta 4
Copyright ©2000 - 2021, vBulletin Solutions, Inc.
×