Grit blasting and gel coat

[guydickinson]

I have many years of antifouling - probably 35 odd - leaving a v rough cratered hull. Wondered about blasting it off but does anyone know how safe it is in terms of the gel coat? Should one paint epoxy on anyway even if it looks OK after that (ie the surface damage as a result??)? Thanks v much.

 

[Twister_Ken]

It's safe, as long as you have a competent operator. Past threads have suggested several good contractors.

Epoxy? You may find it will take a long time for the hull to dry out sufficiently for epoxifying. That's what happened in my case. So I put on three coats of underwater primer, and two of hard racing as a base.

 

[Bilgediver]

I have many years of antifouling - probably 35 odd - leaving a v rough cratered hull. Wondered about blasting it off but does anyone know how safe it is in terms of the gel coat? Should one paint epoxy on anyway even if it looks OK after that (ie the surface damage as a result??)? Thanks v much.

If you blast with grit you might finish up with no gel coat! Get an experienced fella as others have said who will use a fine sand. These chaps can even remove the antifoul layer by layer. Your catered surface is just varying thicknesses of anti foul and will look totally different when all the old coatings are removed. Hopefully there will be no blisters. A good base for the new antifoul is Primocon.

 

[oldsaltoz]

Slurry blasting is what I would use, a bit slower but a lot less agresive and controllable, the finish is a tad smoother to.

A set of moisture reading above and below the waterline should give you a very good indication of moisture content.

If has been epoxy coated before, it would be wise to re coat it.

Avagoodweekend......

 

[seadog30]

Sand blast

I recently purchased a 30 foot seadog with at least 20 years anitfoul, the surveyor recommended cleaning of all of the hull to check the condition.

As I did not fancy 3 weeks on my back in the yard with a one inch chisel we called in a professional boat blaster. Job done in a few hours, the gelcoat was just slightly abraded (ideal for primmer coat).

I would recommend Symblast (they have a web site) if you are in the south, two guys turned up with immaculate kit they protected the boat, worked like slaves on one of the hottest days of the year, and cleaned up to the 100% satisfaction of the yard owner.

The cost was also very reasonable in comparison with other quotes.

They also offered to put on 2 coats of antifouling however I wanted to leave the boat naked for the surveyor to see.

Good luck

 

[sjclewes]

hi there symblast just did mine brilliant job and my hull had just been respray gell coated

 

[Deleted member 36384]

If there is any moisture trapped in the hull then do not Epoxy coat the hull as you will trap in the moisture. My own boat has moisture in the hull which I am not bothered about, but I was specifically advised against Epoxy coating the hull. I think its because moisture levels in the hull are dynamic and its better not to restrict this dynamic process.

What Twister_Ken advises is more or less what was advised by the surveyor.

 

[Ubergeekian]

I have many years of antifouling - probably 35 odd - leaving a v rough cratered hull. Wondered about blasting it off but does anyone know how safe it is in terms of the gel coat? Should one paint epoxy on anyway even if it looks OK after that (ie the surface damage as a result??)? Thanks v much.

Have you thought about paint stripper? I have had very good results with the Removall stripper sold by paints-stripper.co.uk (just a happy customer). It works brilliantly, if slowly, and is non-caustic, non-toxic and biodegradeable.