Patching holes in a firewall
Posted: Mon Mar 22, 2021 7:38 pm
Working on a PA-18 cub project. It has the galvanized steel firewall. What are the standard materials (not methods) for patching various holes? Some are just old screw holes that need a solid rivet. Some are 1"+ from old penetrations that will need a patch.
Do folks use aluminum rivets in a steel firewall? Is the dis-similar metal an issue? The mechanic wants to use solid steel rivets and steel patch sheet stock. My argument is that there are hundreds of aluminum rivets in the aluminum boot cowl that attaches to the firewall. We should just zinc chromate and use solid aluminum rivets. I can't even seem to find solid steel rivets in the standard aviation supply locations
I know this is not a 170, but the principle applies.
Thoughts?
Do folks use aluminum rivets in a steel firewall? Is the dis-similar metal an issue? The mechanic wants to use solid steel rivets and steel patch sheet stock. My argument is that there are hundreds of aluminum rivets in the aluminum boot cowl that attaches to the firewall. We should just zinc chromate and use solid aluminum rivets. I can't even seem to find solid steel rivets in the standard aviation supply locations
I know this is not a 170, but the principle applies.
Thoughts?