Cleaner/solvent

[63robskin]

Are there any cleaners or solvents that can damage the flexiglass either by direct contact or simply by the fumes? Getting ready to prime and paint interior around windows of RV10.

[Kyle Boatright]

The only solvent that (generally) won't damage plexi is mineral spirits, and I wouldn't go overboard with that. Acetone and other harsher solvents can damage the plexi.

Your best bet is good ventilation and good masking of the windows.

[63robskin]

Can I clean the fiberglass with mineral sprits and then apply primer?

[az_gila]

These solvents work too...

To remove tar, grease, paint, etc., use a good grade of naphtha or kerosene. Users of these solvents should become familiar with their properties to handle them safely.
Do Not Use: Window cleaning fluids, scouring compounds, gritty cloths, leaded or ethyl gasoline or solvents such as alcohol, acetone, carbon tetrachloride, etc.

From here -

http://www.aircraftwindshield.com/faqs.html

[Kyle Boatright]

Originally Posted by 63robskin

Can I clean the fiberglass with mineral sprits and then apply primer?

A wax and grease remover (available through your local body shop) is probably a better choice. The fumes shouldn't be a problem in a well ventilated space, but you don't want to get it on the plexi.

You douse a cloth in it, wipe the surface, then wipe again with a dry/clean cloth to remove whatever the cleaning solution has picked up.

[BillL]

Originally Posted by 63robskin

Can I clean the fiberglass with mineral sprits and then apply primer?

I would not do that alone, do a final clean with isopropyl alcohol at least 91% then blow dry. The last 9% is water. Pure ethanol would be nice, but you never know what denaturants are used to keep people from drinking it. Sometimes methanol, so I try to stay away from store-bought ethanol for plexiglass. You could test it on a sample.

Have you considered flame passivation treatment to improve the adhesion? West testing showed it improved epoxy adhesion significantly.

PrepSol solvent is mineral spirits, naphtha, and toluene. The first two are ok for plexi, doubts about toluene. Check the SDS for magic mixtures.

[lr172]

Originally Posted by 63robskin

Can I clean the fiberglass with mineral sprits and then apply primer?

Yes, but must be followed up with a W&G remover before primer as Kyle mentions. Mineral spirits and other less aromatic solvents leave a film that will hurt primer adhesion. If using MS, I would want a solvent based W&GLL remover, not water. Laquer thinner is fine before water based W&G remover.

Larry

[rvmv]

Do you have some scrap left over? Try the stuff you want to use on a piece and see what happens.