New layer of resined 1708 on older layer

[wallybme]

Can you put a new layer of resined 1708 on an older layer? I just want to seal some of the cracks. Do I have to resand the older layer?

 

[Woodonglass]

Re: New layer of resined 1708 on older layer

I'd recommend always sanding with a minimum of 60 grit and wiping down with acetone before applying any new resin and glass over old glass. Well.... How old is this glass???

 

[alligatorgars]

Re: New layer of resined 1708 on older layer

Ive seen a few 25 yrs plus old boats being restored for offshore use. Is doing this asking for trouble considering the hull is only as strong as the poly that was rolled out 25 years ago? Will this poly become brittle and prone to hull splits? Putting around sweet water old man style is one thing but the beating big water can give is relentless on any hull. Ive always wondered what the shelf life was on these poly resin glass boats. Would adding a layer of 1708 increase the structural strength of these hulls without adding to much weight?

 

[Woodonglass]

Re: New layer of resined 1708 on older layer

That's a question that Yacht Doctor would be best qualified to answer. You might send him a PM.

 

[ondarvr]

Re: New layer of resined 1708 on older layer

A laminate will fatigue over a period of time and lose strength. The one thing most hulls have going for them is they significantly over built when new, so even though they weaken over time they typically hold up well.

http://www.mdi.espci.fr/~chateau/Fatigue/fatigue.html

 

[wallybme]

Re: New layer of resined 1708 on older layer

I guess I'll sand, wipe with acetone then reglass with the 1708.
http://i409.photobucket.com/albums/pp177/omeidea47/IMG_7824-2.jpg This is what it looks like the plywood (marine type) is solid, was carpeted and just shows cracks in the glass.