How to safely strip paint from GRP?

skyflyer

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Previous owner had a rather poor sign writing job done on the bow, painted, not vinyl lettering, irregular and at an angle, so I want to remove it and re-do it properly even though we aren't changing the name!

I'm guessing its ordinary black gloss paint - how do i strip this safely without damaging the gelcoat of the GRP hull?

I'm guessing that Nitromors will not be a good idea and a scraper is going to damage the hull for sure!
 
Thanks for that - I was anticipating a bit of polishing out to try and blend the new and old and anyway new lettering will be applied in the same area which should help
 
I have had very good results with Removeall 220, which used to be sold for GRP but is now listed for metal and brick, and shockingly poor results with Removeall 620 which is the current GRP stuff. Old fashioned Nitromors (dichloromethane based) was not recommened for GRP but Rustin's Strypit, with the same ingredient, was. Modern Nitromors may be safe for gelcoat ... it certainly seems to do stuff-all to paint.
 
Previous owner had a rather poor sign writing job done on the bow, painted, not vinyl lettering, irregular and at an angle, so I want to remove it and re-do it properly even though we aren't changing the name!

I'm guessing its ordinary black gloss paint - how do i strip this safely without damaging the gelcoat of the GRP hull?

I'm guessing that Nitromors will not be a good idea and a scraper is going to damage the hull for sure!

Use Dilunett for getting paint off GRP. You may find that the gel coat has faded differently behind the signage so it will still show, but will weather away in time.

It is methylene chloride ( aka dichloromethane) based paint strippers that should not be used on GRP. The traditional Nitromors was methylene chloride based.

However methylene chloride based products have not been available on the retail market for some time which menas that any painstripper that you can buy over the counter now will be safe to use on GRP. It is however still available for industrial and some professional use and is no doubt obtainable via ebay etc so be aware.

Dilunett is now an Owatrol product and available on the domestic decorating market as Dilunett Gel
The equivalent product on the marine market is now known as "Marine Strip"
They are caustic soda based, which is safe to use on GRP.
I dont know the difference, if any, between Dilunett Gel and Marine strip.
 
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Old fashioned Nitromors (dichloromethane based) was not recommened for GRP but Rustin's Strypit, with the same ingredient, was. Modern Nitromors may be safe for gelcoat ... it certainly seems to do stuff-all to paint.

The safety data sheet for the old formula Strypit says it "Will degrade and cause severe damage to rubber, linoleum, fibre glass, vinyl floor covering, perspex and plastic"

The new formula stuff is probably about as effective as the new formula Nitromors.
 
I've followed a few of these paint stripper threads as I'm looking for something to remove the anti slip paint form my deck. All the threads seem to follow the same course:

Someone asks what will take paint off GRP without damage
Someone suggests a product
Someone suggests another product
Someone suggests Nitromors did do it but it doesn't anymore
Someone suggests that the first product does it, but it's changed its name
Someone suggest that Nitromors did do it but you can't use it any more
Someone suggests a product that doesn't do it. May be the same as the first product suggested
Someone suggests that Nitromors did do it, but you can't buy it any more. But if you could buy it, it probably would damage the GRP
Someone suggests oven cleaner
someone suggests Persil washing liquid
Someone suggests just painting over it, sanding it off, or buying a new boat.
From this point on, the thread generally slides into confusion and conflicting comments about which paint stripper didn't work.
 
I tried Nitromors once ...never again. I would try a very sharp scraper - with luck the offending paint will be brittle and come off as flakes or splinters. Hold the scraper very firmly in order to control its pressure against the hull - enought to dig into the paint but not through into the gel coat.
 
The safety data sheet for the old formula Strypit says it "Will degrade and cause severe damage to rubber, linoleum, fibre glass, vinyl floor covering, perspex and plastic".

They must have got more nervous lawyers, as they used to say it was OK on GRP.
 
I've followed a few of these paint stripper threads as I'm looking for something to remove the anti slip paint form my deck. All the threads seem to follow the same course:

the thread generally slides into confusion and conflicting comments about which paint stripper didn't work.

Several possible reasons for confusion including the facts that there are a variety of paint coating types some of which are more resistant to chemical attack than others. Single pack, two part, alkyd, polyurethane, chlorinated rubber, etc.
The formulation of coatings changes.
The formulation of paint strippers changes.

All the evidence is anecdotal.

Faced with an unknown coating all one can do is try the various products currently available including some of the alternatives if to hand.
You might be lucky. You might have an alkyd resin paint and you might choose an oven cleaner based on caustic soda or caustic potash then it will come off easily.
 
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The stuff from Cirrus Systems is excellent. I used it to strip a whole fibre glass bodied car recently with no problems at all.
Very easy to use and clean up afterwards too which is important.
 
The stuff from Cirrus Systems is excellent. I used it to strip a whole fibre glass bodied car recently with no problems at all.
Very easy to use and clean up afterwards too which is important.

Which did you use? As I wrote, I have had very good results on GRP (cars and boats) with 220 but abject failure with 620.
 
Fairy Power Spray, available from all good supermarkets. You have to leave it on for a while.

Being a man, I don't clean my stove (at home) very often, so I used Fairy Power Spray and left it on for an hour instead of the suggested time limit. It completely removed the markings around the gastaps! Definitely worth a try.

Rob.
 
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