Stripping antifoul back to gelcoat for epoxying

[pcatterall]

I have just had the antifoul cleaned off back to the gelcoat (Farrow System job).
The type has no history of osmosis problems, nor is there any sign of a problem on mine.
Should I bother with the time and expense of applying Gelshield or similar, or just slap antifoul primer on it and go from there?


More thread drift. My Nigel Clegg reading suggests to apply epoxy when the boat is quite new and dry or after blistering has developed ( following full gell coat removal and treatment of course) In the intermediate period when Osmosis may be developing but not showing epoxy treatment is not worthwhile.
Bengt Blomberg suggests ( but I have yet to read the entire report) that epoxying is no use at all !! and that an element of porosity is no bad thing!!

 

[afterpegassus]

I would suggest sand blasting to strip. It can be done with a Kaarcher pressure washer and bags of kiln dried sand.
Rob.

could you expand on this? what size washer? what type grit? how much / sq m etc. Most posters seem to favour the scraper & elbow grease method but if there is an easier diy method then I would be interested

 

[oldsaltoz]

Originally Posted by rob2 View Post
I would suggest sand blasting to strip. It can be done with a Kaarcher pressure washer and bags of kiln dried sand.
Rob.

I do hope it's not sand. It's illegal to blast with sand because it's a silica base and will cause major heal problems.

The use of sand to blast anything has been banned for many years, in Oz at least.

 

[Phideaux]

Originally Posted by rob2 View Post
I would suggest sand blasting to strip. It can be done with a Kaarcher pressure washer and bags of kiln dried sand.
Rob.

I do hope it's not sand. It's illegal to blast with sand because it's a silica base and will cause major heal problems.

The use of sand to blast anything has been banned for many years, in Oz at least.

Same in the UK because of the dangers of silicosis caused by inhaling the fine sand (silica) dust generated by sandblasting. BUT I believe the Kaarcher is a wet 'domestic' DIY car wash system at relatively low pressure compared to an industrial 'sand-blast' setup. It sounds like there is an attachment that you can add to feed grit into the pressured water-stream. So, probably more like a wet slurry; you'd probably inhale more silica spending a day on the beach.

 

[vertford]

Remov-all

..is what I am planning to use next year. Apparently good stuff and GRP safe.
Did see Dilunett in the chanderly yesterday which is said it was GRP safe.

Guess I better read up on expoxing a 40 year hull aswell.

 

[mainmarine]

Same in the UK because of the dangers of silicosis caused by inhaling the fine sand (silica) dust generated by sandblasting. BUT I believe the Kaarcher is a wet 'domestic' DIY car wash system at relatively low pressure compared to an industrial 'sand-blast' setup. It sounds like there is an attachment that you can add to feed grit into the pressured water-stream. So, probably more like a wet slurry; you'd probably inhale more silica spending a day on the beach.

I have a sand blaster attachment for my Kharcher washer. it is a simple metal jet with a plastic "Y" pipe, one end fits onto the outlet nozzle on the washer, the other end rests in a tub of sand and sucks up the sand as the water pressure blasts the surface. The sand must be perfectly dry, as soon as any moisture reaches it, down the feed pipe, it blocks up. It is ok to use on small items but I imagine it would take an awful long time to do a complete hull.