Sealing old fibreglass

[jono]

I would like to seal the interior of my shell mainly to stabilise and reduce dust release and provide a sound surface for final trimming and gluing in the sound proofing

Has anyone done this before and what have you used?

Last time I used Gravitex, just wondeirng of there is anything better?

Cheers

Jon

[HCA]

What are you trying to achieve - Gravitex, whilst good, is rough and maybe better suited to stone chip prevention - do you want a smooth finish (your word 'interior' determines the question...

If it is interior and you just wish to have it nice and smooth - why not try paint-on gelcoat, or even a good quality epoxy paint? I have painted on gelcoat many times with great success - but only do it onto existing grp as it does not like paint or sealers...

[jono]

Exactly that - the interior of the shell only, which is in 'powdery' conditiom

I've done the entire underside with Gravitex. Doing the interior with it works and would increase resistance to 'drumming' but just wondering if there is anything better.

In essence I just want to stabilise the interior surfaces which are just raw fibreglass so brushing/rollering on gel coat may well be the way to go

[HCA]

I have no idea how Evostick will adhere the deadeners to Gravitex - but with a paint-on gelcoat, well it will stick like glue..
I would say its the way to go. Get a handful of disposable brushes, and make sure you get close into the corners to see what you are doing - the smell is intoxicating. And legal (but do use a mask when mixing the stuff, please!)

[h20hamelan]

Dynamat, or similar. You do not need much, i use 1/2” strips in a star pattern, stops the “drumming”, i also used some marine paint to seal the glass after i did some reinforcing near bobbins and below driver/pass legs (i am always scared of road debris coming through floor).
Gel coat, or a skim coat of polyester, or the poly with added fibres?

[snowyelan]

Maybe a simple coat of polyester resin? Anything that isn't polyester based may make future repairs a bit more difficult. Gelcoat would work too but I believe its a laminating type product so may remain a bit tacky.

[jono]

I have no idea how Evostick will adhere the deadeners to Gravitex - but with a paint-on gelcoat, well it will stick like glue..
I would say its the way to go. Get a handful of disposable brushes, and make sure you get close into the corners to see what you are doing - the smell is intoxicating. And legal (but do use a mask when mixing the stuff, please!)

It sticks very well to Gravitex at least it did on my last project

[vstibbard]

I’ve used gelcoat in past and been very happy.

[StressCraxx]

I’ve used gelcoat in past and been very happy.

Before sealing, suggest gently warming the area to be sealed so the moisture absorbed between the fiberglass strands dry out to avoid blistering later. Very important where it's cold and humidity is high.

[h20hamelan]

Mainly if the fibres are open (white), creates bubbles. Which, for Canuckleheads, is okay!

!