One part primer over cured resin?? pics

[rebuilt]

I sure would like to prime these repairs instead of gelcoating them all. I have no air equipment. Any gelcoat work will be by hand. I think I've got to coat the outside of the new transom with new gelcoat, but do I have to gelcoat all of the little patches? I'm going to make up some cabosill putty to fair out the rough spots, and little nicks in the old gelcoat, but after I get the rough spots smoothed out with cabosill, can I just prime with Easypoxy white undercoater? This boat will be trailered everywhere it goes. Thanks in advance. KR

 

[drewpster]

Re: One part primer over cured resin?? pics

Interlux makes a product that will do both jobs for you, smooth the surface and protect your bare fiberglass. It is called Interprotect Watertite epoxy filler. (see link below) I have used it as a fairing compound and a filler and it works great. You can use it on the repairs you have made and then prime over it to prep for paint. Great stuff. It is easier to use than the cabosil mix you mentioned and it sands like wood until it fully cures.

"http://www.jamestowndistributors.com/userportal/show_product.do?pid=4148&familyName=Interlux+InterProtect+Watertite+Epoxy+Filler"

sidenote: I normally do not post product links outside of iboats, but I did not see this product offered in the iboats store. Check the iboats store, I may have missed it.

 

[drewpster]

Re: One part primer over cured resin?? pics

This pic gives you an idea how much I like watertite filler. The whole boat needed it.

sand, sand, more sand

 

[rebuilt]

Re: One part primer over cured resin?? pics

Thanks drewpster. I noticed you were on the board today, and was hoping you'd reply. OK... I read the info Jamestown posted and couldn't find the answer I'm looking for. This stuff is a 2 part epoxy. Some questions.....Will the white undercoater primer by Pettit bond to it? I already have a gallon of this primer, as part of the easypoxy one part polyurethane system I'm going to use. I also have already bought my paint, again, the one part polyurethane by Pettit. Will roll and tip. What about my transom? Hand apply gelcoat? Which I also have a gallon of with a separate wax additive to ease sanding. Or prep the transom for this two part epoxy system then prime? Will this stuff take the place of gelcoat, since I'm going to prime 2 coats then paint 3 coats? Again, this little boat will be a trailer queen. No sitting at a marina slip for days and months. Thanks in advance, KR

 

[sbklf]

Re: One part primer over cured resin?? pics

Maybe I missed something but why couldnt you paint the transome with the Easypoxy (if this is the one part poly you have) like the rest of the boat?

 

[rebuilt]

Re: One part primer over cured resin?? pics

Naw.. you didn't miss anything. I'm not sure if I can do that. That's my whole question. Can I just use a couple of coats of primer, followed by the coats of paint over all of the exposed glasswork? I'd like to prime and paint all of it, after the nicks and rough spots are smoothed out. The original hull is 30 yrs old, and much of that glass was exposed in the process of making the repairs. I've got a lot of area to waterproof, the transom, and those patches in the pics. The keel was pretty bruised up, so I cleaned it up, and repaired it as well. I really don't want to go crazy with the gelcoat. I've read it can be difficult to work with without a spraypot. And hard to sand. I was not looking forward to attempting a full gelcoat transom coat. But had kinda resigned myself to it. There isn't a flat spot over a couple of feet long anywhere on my hull, so I really want to minimize the sanding thing. I have no spray equipment. But have a gallon of good one part primer, and a gallon of good one part paint.

 

[sbklf]

Re: One part primer over cured resin?? pics

I am repairing my boats transome and sole with Epoxy. I would have used gelcoat but it wont bond to the Epoxy repaired areas so I chose to use the Pettit White undercoater/Easypoxy combination. I was concerned with painting the transome since it has an outboard wondering if the paint would be hard enough not to indent when the motor is mounted. I have already painted the transome earlier in the project in hopes it will get plenty hard with time before mounting the motor. I was careful to apply the primer and paint thin and let it dry a day between coats as they warn of a soft finish if thick coats are applied. It seems to be very hard after three weeks. What is your concern?

 

[Chris1956]

Re: One part primer over cured resin?? pics

Folks, Epoxy and polyester resin products as well as primers will bond to poly resin as well as epoxy resin. The key is to wipe all surfaces with acetone and then sand all surfaces to allow a good bond, and wipe again to get the dust. I have put poly putty over epoxy repairs, without incident. I have also made epoxy repairs to the original hull (poly resin) w/o incident. The key is preparation!

The primer will bond very well to the poly repairs you made. Make sure you have filled the mesh of the cloth with resin, and then sand smooth with a fine grit paper. Wipe it down and "prime" away.

 

[rebuilt]

Re: One part primer over cured poly resin? Will it waterproof as well as gelcoat?pics

Re: One part primer over cured poly resin? Will it waterproof as well as gelcoat?pics

Thanks Chris. Prep work has made some killer bonds on this project. I'm good to go. It's all polyester.
Concern #2, Will the 2 coat primer and 3 coat paint combo waterproof the glasswork as well as gelcoat?
I did go ahead and mix up some cabosill to fair out the rough spots. I had it on hand. The other stuff that drewpster uses is probably great stuff, but I have a small boat, and don't need a lot of it. I've got a time window to play with. Don't want wait for it to ship. Again, thanks. KR

 

[Chris1956]

Re: One part primer over cured resin?? pics

Gelcoat and poly resin are already waterproof. if there are uncured areas of the poly resin (incomplete mixing), you may get blisters, however, it is likely you mixed the resin well enough that this will not happen.

Only an epoxy barrior paint (and the right number of coats) will seal the hull better than the poly resin. Regular marine primer and paint do not seal the hull.

 

[BillP]

Re: One part primer over cured resin?? pics

Relax, you will have no problems painting easypoxy over glasswork even without their primer. It's durable and won't peel if you prep by cleaning and light sanding. Not as tough as interlux brightsides in my opinion but is a close second. I'm speaking from using both easypoxy and brightsides with and without primers over several decades.

 

[drewpster]

Re: One part primer over cured resin?? pics

Sorry for delayed response, family is coming for Thanksgiving. Whew!

rebuilt, You should have no problem going with whatever combination you use to cover your repair areas given that your boat is trailered. It is my understanding that finishing a repair with gelcoat is primarily done on boats where gelcoat is going to be the boat's final finish. Since you are planning to paint this is not a concern.
There is also the issue of water intrusion as well as the gelcoat serving as protection against ultraviolet light damage to the underlying poly.
Again, since you are painting and the boat is trailered it is highly unlikely that water intrusion will be a problem as long as your repairs are good. Most modern polyurethane marine paints also have U.V. inhibitors in them so sunlight will not likely be a problem.
Most marine primers do help with adhesion of the paint but it is not the primer's primary function. Poly primers are mainly used as a surfacer. The primer is there to bring the surface absolutely fair and smooth. The paint will bond to your repairs as long as your prep is done correctly. It is important not to sand your repairs before cleaning them with a good dewaxer and make sure that you do some finish sanding to give a good bite. If you used epoxy to do any of the work at is a good idea to use a scotbright pad and clean water to scrub the surface of the epoxy to remove any possible amine blush prior to sanding. Sanding alone will not remove wax or blush. It can drive the contaminates into the surface making them harder to remove. (don't fret if you have already done some sanding, just wipe it down with dewaxer and continue wiping regularly while sanding, change the sand paper as well)
I recommended the Watertite fairing compound because it much easier to sand and also will protect the bare spots from water and light as well. The cabosil will work too but I would recommend using some micro-balloons in with the cabosil to ease sanding. Can you tell I hate to sand?
Post some finish pics when you get it done, love to see it
Drewp