Epoxy/gelcoat removal

[steffen]

To cure a osmse problem I want to remove the five layers of epoxy and the gelcoat to bare the grp.
I started with part of the keel with a band sander but that proved a very tedious job. I then tried the hot air gun and warmed the upper layers and scraped it of easily.

Q: could anyone shed a light on the concequences of this heating on the remaining grp. Does it alter the chemical stability or any other properties in any way?

Your advices welcomed.

Happy sailing,
Steffen

 

[savageseadog]

Don't use heat, it will degrade the GRP, I don't know about the exact chemistry.

 

[Finnsailing]

The local boatyard had a boat stripped last year . Looked like someone had used a plane on it . Must be a special tool . You could try a power plane with it set fine so start with and see what happens . If should not create to much dust if you use bag for it . Would certainly wear a mask and goggles no matter what you are doing . Hope you have as much fun as I did putting on antifouling /forums/images/graemlins/smile.gif

 

[john_morris_uk]

The two recognised ways are using a 'stripper' machine, which is an air powered power plane which is specially designed to be able to follow the curvature of the hull, or to use grit blasting.

Both are specialised jobs that are best to pay a company to do for you IMHO.

 

[fastjedi]

There was an article in one of the sailing mags about 8 - 12 months ago (probably PBO) about DIY osmosis treatment on a motorsailer (LM27?). I am fairly sure the gel coat was removed by hot air gun and scrapper

 

[oldsaltoz]

G'day Steffen,

What grit was on the belt sander? I would think a 40 grit will remove it in a hurry.
I have stripped a few hulls with a 5 inch angle grinder fitted with a concrete grinding wheel, rapid but dusty, so you need a good mask (Not a paper one) goggles and ear plugs.

Avagoodweekend......

 

[Sammy]

Dont use a sand blastif it has been epoxied you are liable to end up with very deep holes when it breaks through the hard epoxy layer into the softer gel coat.
Heat stripping is ok with care.

Chris

 

[yoda]

Having tried shot blasting and seen gel peeling I would go down the gel plane route. Expect to pay in the region of £500 ish. Don't be surprised at how long drying out takes.

Yoda

 

[steffen]

Thanks for all advises. Combined with other info from polyester specialists i will go for the diy option with the heat gun followed by prolonged dry out, a new layer of GRP topped off with five layers of epoxy.

Very good point made abour gritblasting through epoxy over polyester. Never ever do it. My neighbour, albeit no professional, blew right through his hull before he knew what happened.

OldSaltz; i love your motto.

Happy sailing, Steffen