Advice on replacing broken canvas snaps on aluminum hardtop

[dstarok]

My 1989 Sailfish 252 had snaps on the hardtop support aluminum tubing when I got it. They were old and not taken care of, but most of them were useable when I had isinglass enclosure installed. 2 years later, I need to remove and replace a lot of them. It looks like they are riveted to the aluminum? Can I just punch the broken off ones through into the tubing with a center punch? I also want to remove and replace a lot of the ones that are still there that are corroded too much. Anyone go through this?
Thanks

 

[DennisG01]

Re: Advice on replacing broken canvas snaps on aluminum hard

You have to drill them out. Then you can re-rivet new ones back on.

 

[dstarok]

Re: Advice on replacing broken canvas snaps on aluminum hard

Oh boy. Another fun job! Any tricks to make drilling easy?
The ones that are broken off are going to be tough to drill out!
I guess try to file them down flat to the aluminum, then center punch them.
Maybe a Dewalt pilot point bit might help stay in center of the hole?

 

[DennisG01]

Re: Advice on replacing broken canvas snaps on aluminum hard

It's not as bad as you think. The toughest part is just figuring out what size drill bit to use and using the right amount of pressure to avoid the rivet "spinning" as the bit spins. The goal is to get a drill bit that is the same size as the shank of the rivet. Bring a couple different sizes and just experiment - you'll figure it out pretty quickly. Once you drill the exposed part off, the shank will fall into the tube.

Regular drill bits will be fine since there's already a hole in the middle of the rivet to center the bit.

Small, needle-nosed pliers can help to keep a rivet from spinning (especially the broken off ones if they're loose) - also a small screwdriver can sometimes help by wedging it in to create more tension on the rivet.

It's really not that bad - once you get the hang of it, it might take about 30 seconds per rivet to drill it out.

 

[dstarok]

Re: Advice on replacing broken canvas snaps on aluminum hard

Thanks for the info!

 

[Curmudgeon]

Re: Advice on replacing broken canvas snaps on aluminum hard

Try to figure out what the 'new' hole size will be before going all in. There are snaps that have stud screws, easy in and easy out later, if necessary ...

 

[journeyman]

Re: Advice on replacing broken canvas snaps on aluminum hard

A drop of oil on the tip of the drill bit will help keep things lubricated and cool.

Slow / Low speed is key to keeping things cool. Speed equals friction.

Watch out for the bit "grabbing" near the end. Ouch!

You don't need to drill all the way through. If you drill off the rivet head, you can push or punch the shank into the tube.

 

[dstarok]

Re: Advice on replacing broken canvas snaps on aluminum hard

Replace with river or screw? Stainless or aluminum hardware?

 

[DennisG01]

Re: Advice on replacing broken canvas snaps on aluminum hard

Replace with river or screw? Stainless or aluminum hardware?

I definitely wouldn't use a river - that would be tough. But a riveT or a screw is fine. :mrgreen: A rivet would be my choice in this application - Al is easier to work with than SS.