4+2 Tonneau turnbutton replacement

[Clive]

Hi all. Has anyone knowledge or experience in replacing riveted turnbuttons?
The ones I need to replace are in front of the cockpit screen. Under this in the cabin is a substantial cross member, I assume timber. I can’t see how to drill them out as the body of the rivet will stay in the GRP.
Help welcome!
Cheers Clive

[Clive]

I have the replacements in stainless, what I need to know is how to remove old rivets when they are embedded and don’t appear on the other side without damaging the GRP.
Cheers Clive

[Mdr24uk]

Wouldn’t there have been a void behind the GRP skin to allow the rivet to form behind when pulled?
If you drill out the core then the old rivet tail will then fall down behind?

[Freebird19]

Could it be possible "blind" rivets were used? These don't need to protrude through to the other side. I did have to drill one rivet, a hook type for elastic loop, as it would not knock through once the head was drilled off. I used a drill bit the same size as the rivet body and only drilled as deep as the new one.

[Clive]

Mark - knowing my luck no, plus they would rattle away when motoring!!

Freebird, you may well have answered it. Pretty careful drilling tho. Did you first drill out the old rivet then enlarge to fit the replacement or do it in one?

For some reason I have quite a lot of anxiety about the drill slipping and gouging the boat. I looks straightforward enough on YouTube!
Thanks for the pointer, Screwfix to the rescue.

[Freebird19]

These might be more suitable. They imply that they are sealed, not leaving the centre hole left by the pop part of the rivet?

Slowly, slowly is the way. Start with a smaller drill, 1.5 ish and build up to the original rivet size. I think mine where 4mm? Being aluminium they might work better on gelcoat and GRP. I've not used them, anyone else have experience with them?

[Clive]

These look good. I think I'll try to track down stainless as any steel is going to rust, but I like the sealed end.
Thanks again, Clive

[Clive]

Or, do you think I could use screws into the void after drilling out the old river? Not convinced so thought I’d ask!