Removing Glassfibre Sheathing

[hosscartwright]

I'm thinking about taking on a restoration project to keep me amused for a few years. I'm interested in taking on an old fishing yole that has unfortunately been sheathed in glassfibre at some stage.

I'm fully aware of the reasons why this took place in the first place and the implications for the remaining (if there is any!) timber underneath. What I would like to know is if anyone has any experience of trying to remove the dam' stuff!

Is it pretty straightforward or does it turn into a nightmare? Is there any problem apart from light surface damage to good timber whilst ripping off the GRP?

I'm not looking to do a concours or show standard job, just take her back to how she would have looked.

Any thoughts???

 

[Mirelle]

No expert, but the fibreglass sheathing that I removed from my knackered old Dragon thirty-odd years ago fell off in sheets! No doubt it was applied using polyester resin. If epoxy has been used I expect it will soften under a heat gun; it is not at all resistant to heat.

 

[Peterduck]

My own experience at trying to undo an epoxy-glued joint with a heat gun resulted in charred wood before the joint reluctantly let go under a fair bit of wedging force. I will never have any worry about epoxy letting go under hot conditions. I think that I would fall off the twig if I were to be included in those conditions.
If the binding resin is polyester, on the other hand, one needs to be quite careful about using heat. Once polyester reaches flash point no fire extiguisher in the world will hold it back, and you will be left with a pile of glass fibres, ashes and assorted fastenings.
This begs the question; how does one distinguish between cured epoxy and cured polyester? I think that one would have to remove a piece from the boat by mechanical means, heat it up and see whether it just melts or bursts into flame. If your nose is more sensitive than mine, you may be able to sand some of the mat and smell whether it is oneor the other. Polyester has a sickly sweet smell that I detest.
Peter.

 

[kestrel1891]

When I removed the polyester glass fibre sheathing from Kestrel I found that about half fell off in large sheets whilst the remainder was very well stuck.

I used a gas torch to heat it up a bit and then scraped it off. Peterduck is right about the flamability. An extremely unpleasant job what with burning polyester landing on you, glass fibres going up your sleeve plus the fumes from the resin and antifouling.

 

[Mirelle]

We have an expert, here

Since I know the boat, and knew her before the award-winning rebuild, I reckon I can say what Kestrel is too modest to say for himself.