Critical temperature for Fiberglass

[Smelly]

Does anyone know what the critical maximum temperature is before fiberglass on boats begin to weaken?

Thanks

[Blackened]

G'day smelly
Just out of curiosity, why do you wish to know this? at a certain temperature (I do not know how high) the gelcoat will start to burn and turn a brown colour. I would imagine if this was to persist, the damage of the structural integrity of the fibreglass wouldn't been too far away.

Dave

[wessel]

We work on ambient plus 30 degrees C to get a black metal temperature.
Over here that means we design pipes etc to operate in 80 deg C conditions.
Industrial fiberglass will handle those sort of conditions, but any more and the stuff will be affected by the temperature.

Fiberglass used in a boat is a different story. There are just too many variables, but what is your concern?

Have you seen stuff delaminating? Did your kid accientally set fire to a section of the boat, did the bbq falll over on the deck, is something buckling?????

Wessel

[Smelly]

I am trying to get damn stickers off the hull - been there since 1989 - and are about 180mm long by about 70mm..

Used an air gun recently with digital read out - half way getting the f..ckrs off but uncertain if I am damaging the fiberglass in the process by applying too much heat.. :-/

I have varied the temp - from 60 deg C up to 220 deg C - for short periods of time..

SHoudl I be concerned?
:-?

[wessel]

Stand back and look at the unpainted side of the fiberglass surface. If there is no major discoloration you should be OK.
Press lightly on the area and see if there are any hairline cracks or brittle sections falling off. The easiest way to check for hairline cracks is to spray a light mist of water on the surface. Use a towel to dry the surface off. Now dust the surface with blue marking chalk.
The water trapped in cracks will discolour the chalk and you should be able to see major damage very easily.

If you did not do any heat damage to the painted surface the stickers were on when you used the heat gun, then you should be OK.


Wessel

[Smelly]

Thanks Wessel.