Glassing over old paint?

[John Stevens]

My pram (built 2 years ago) has had some checking problems where I didn't put fiberglass. I'm starting to sand and I'm going to glass, I think. Do I have to get "all" the paint off. I'm using 80 grit with an orbitting sander and I'm having a hard time getting to the bear wood.

1.Can I glass over this or will it pull away from the paint eventually?

2. Can I epoxy at this point and forget about glass? How long will it hold up now that I took off the high spots?

None of the above?

What would you guys do next?

TIA,

John

[Charlie Jones]

Sorry John, but yeah- you're gonna have to get rid of the paint. Might try a stripper rather than sanding, at least to get the bulk of it off. You might get away with leaving some small areas of paint, but anything large will eventually delaminate. Paint down in the grain won't hurt you that badly however if you have good clean wood all around that area.

No, just a coat of epoxy resin won't stop the checking, only a layer of glass will do that for certain.

[John Stevens]

Thanks for the answer CJ, although it wasn't the one I was hoping for :cry:

John

[Pipefitter]

You may try a heat gun and one of those right angle carbide scrapers. After you remove as much paint to where you have mostly wood,you can rough the surface good with coarse paper and get it to stick. Problem with RO's on paint, is the paper gets hot too fast and gums up almost immediately. Anything coarse enough to not gum up is going to leave heavy circle marks and divots.The more fair the surface to start with,the less epoxy fill coats and fairing after.

I just saw a repaint on a hull that was machine sanded by "pros" and I wouldn't have paid them. Nothing short of a rape job.It would take many hours of filling and long board to get that surface even close to right again.The whole hull would have to be skimmed with putty.

[kydocfrog]

There was an article on Duckworks recently about stripping for fiberglassing, or maybe stripping off bad epoxy; I don't remember for sure, but I do remember it used a fairly innovative approach to heat stripping.

DocA

[Guest Oyster]

Well let me throw a cog in the wheels. In the process of doing hulls with enamel paints, on wooden parts, and even skinned fiberglassed hulls, I first use kilz for the primers as a barrier and sealing coat for the glass in a long term project, as I like to continue on the progress of building, sometimes. I will come back and fair the kilz, after a long term curing process and work that has taken place, in most cases with Microlight from West System. The paint and with the help of a guilde coat of black lacquer for sanding the white allows me to really see the highs and lows of the hull surface.

I then fair the hull and will re-prime the hull, fairing, and the old primer with the kilz again. To this day, in all of my enamel projects, I have never had a release of the most expensive paints. I bet if your existing paint is so stuck, when sanding it with a very coarse grit paper, then you would also have no problems with working with epoxy products over the paint that is almost impossible to remove after the rigid harsh sanding jobs. Just my half a cent thought.

[Arnie Eaton]

I have a D4 dink that checked pretty badly. I used an epoxy paste and just troweled the paste into the checks without sanding. After the epoxy cured I spray painted after a light sanding. That was two years ago and today no checks or problems.

[John Stevens]

I bought a stripper and scrapped it down pretty good. Then hit it with a 60 grit paper. I'm down to wood now. I put a layer of epoxy on 2 days ago, then sanded and put the glass on yesterday. It looks good, just need to paint now after sanding that is.

Thanks,

John Stevens