Question about George Kirby Paint

[cthandys]

Hello, this is my first post and my first boat project. I'm building a Sam Devlin dinghy (Guppy) and would like to try George Kirby paint. I'm about to apply the last coat of epoxy on the hull and really cannot find any specific instructions on epoxy surface prep before using Kirby paint. Is there a recommended primer? Will I get a good adhesion? Do I final sand w/ 100 or 220 grit?

Thanks for all information.
Cameron

[Jim Ledger]

Hello, this is my first post and my first boat project. I'm building a Sam Devlin dinghy (Guppy) and would like to try George Kirby paint. I'm about to apply the last coat of epoxy on the hull and really cannot find any specific instructions on epoxy surface prep before using Kirby paint. Is there a recommended primer? Will I get a good adhesion? Do I final sand w/ 100 or 220 grit?

Thanks for all information.
Cameron

The cured epoxy makes a fine base for primer, Kirbys or otherwise.

At the risk of drawing Forum Flack, I'm going to advise you not to sand finer than 120 grit before applying the paint. Sanding finer is a waste of time and only polishes the surface, removing the "tooth" that you're after.

Same goes for varnish and raw wood. (ducks)

If gloss retention is important to you, don't use Kirbys. I know its against Forum rules to say anything negative about their paint, but after a year, their gloss paint goes dead flat.

Edited to add: In my limited experience with one particular color of Kirbys gloss paint, it has flattened out three years running. However, it does sand easily, unlike harder paints. YMMV

[Canoez]

I'd give my epoxy manufacturer's tech line a quick call. I know that some prefer a primer (usually proprietary) before painting - System III comes to mind. <Insert slightly skeptical POV about "Profit Centers" HERE>

Others, such as West Systems say you can coat directly over the sanded and cleaned surface.

I think the issue is more about the epoxy than the paint.

[kc8pql]

At the risk of drawing Forum Flack, I'm going to advise you not to sand finer than 120 grit before applying the paint. Sanding finer is a waste of time and only polishes the surface, removing the "tooth" that you're after.Same goes for varnish and raw wood. (ducks)

I agree. I polish wood (sand past 120 or maybe 150 grit) only if I'm going to use a rubbed oil finish or French polish, neither of which are much use on a boat.

[Thorne]

Why not call Kirbys and see what they say. I suspect that as long as the epoxy is non-blushing and has been washed, dried and sanded, you will have no problems.

What colors will you use? I put their Blind Green on my dory skiff's garboard strake and have been very happy with it, but it comes out a bit lighter looking next to the white hull than you'd expect from their color chart.

http://www.kirbypaint.com/images/menu_newlogo.gif

[JimConlin]

If gloss retention is important to you, don't use Kirbys. I know its against Forum rules to say anything negative about their paint, but after a year, their gloss paint goes dead flat.
If you're painting over a stable substrate like glassed plywood, I'd consider an LPU (two-part) paint. If not abused, it will weather for many years.

[StevenBauer]

I use the semi-gloss. Then you don't have worries like Jim's. :) Ask George. Personally, I wouldn't coat a hull with epoxy unless it was sheathed in fiberglass, but I know some people do. When I built my Harry Bryan Thistle I coated the cedar with CPES and George told me to just paint over that, no need for other primer.


Steven

[Mike Vogdes]

Ah.. Kirby's paint, the best part about Kirby's paint is the directions.
About one paragraph long IN LETTERING YOU CAN ACTUALLY READ !!
Here's the highlights...
Open can, put paint on clean dry surface, get beer, stare at boat.

And yes Jim you should go stand in the corner.

[Russ Manheimer]

No problem Jim, I'm a 100grit man myself. Prime then maybe 120.

Welcome Cameron. I guess I'll be the first to insist on photos of your project.

Russ

[Clinton B Chase]

I'd second Jim -- in the Compass Project Shop we use all System Three paint (water-borne epoxy based LPU) and very low VOC I might add.

It is HIGHLY durable when the second part is added (it is optional to add part 2 making it ever more unique and flexible as a painting system). To attest to it, my students painted past the tape and got some orange on the tan gunwales. With enamels and the like you can take a brand new razor blade and scrape off the paint mistake. Not with this stuff! It was so durable that it would not come off without scraping everything off...pretty amazing.

They should pay me for this post! Actually, they donate thousands of dollars to our cause, so please support them!

Cheers,
Clint

[Keith Wilson]

A note of warning - try a small sample patch first. Some kinds of epoxy can sometimes interfere with the drying of ordinary enamel paint (of which Kirby's is an excellent example). It stays sticky for weeks, if not forever. (Don't ask me how I know this. :rolleyes:) I've been told that the problem is a slight excess of hardener, and that particularly in the last coat, you should always make sure to have a slight excess of resin, which will eventually react on its own and won't interfere with paint. However, I'm no expert, and I'm not 100% certain this is accurate. Take it for what it's worth.

[ddeaton]

I used Kirbys over System Three with no problems at all. Used Kirby primer also. Semi Gloss all the way. Go for it. Good thing about Kirbys is if you mess up a little it will sand out very easy and reapply. After you brush a few strokes on a sample board you will be more than comfortable with it. My 2 cents.

[JimConlin]

I assume that the OP has glassed his boat. Isn't that the Devlin practice? Anyway, I'm REALLY tired of painting (three hulls, two crossbeams, two spars, other loose parts, etc.) and I'm only comforted by the fact that my LPU paint (Awlgrip) will probably not need repainting for ten years.

[Canoez]

My experience follows Keith's. I was using System III epoxy and trying to varnish over it. The epoxy had been on the boat for a few weeks. It was fully cured. I then sanded the hull and cleaned up with denatured alcohol.

After the hull was dry again I put on a coat of spar varnish. It didn't set. Ever. I had to remove it with some acetone and Scotch-Brite. I then went and got the System III brand spar varnish. No trouble. this coating cured up just fine.

I never did figure out why the varnish didn't cure. Test samples on bare wood cured fine. I checked on the manufacture date for the varnish from the code on the can and it was well within their suggested use-by date. Since then I'm a bit gun-shy with putting coatings on the System III that aren't recommended by them. Perhaps the paint will not have similar issues, but that's why I'd call the epoxy vendor for their recommendations.

[BillyBudd]

When it came time to paint my hull, I sent a sample chunk of plywood with cured epoxy on it to George Kirby, he painted it, heated it, and let it lay about for a bit and then he said that I'd not need any primer. So I went with his semi-gloss (or is it semi-matte?) paint (with Penetrol additive per Kirby suggestion) to help hide my less than perfect workmanship. It's been on for maybe 4 years and is great. Even spent an entire summer on the water. My epoxy was Raka.

[cthandys]

Thanks for the info. I'm apply WEST system epoxy over 6 .oz fiberglass. I considered some of the 2 part paints but am trying to keep this first boat simple. I tried emailing Kirby Paints but the email bounced. I'll try calling him but I think the paint will work well over my epoxy. I'll post some pictures after that last coat of epoxy, when it really shines. Thanks again and I'm enjoying the forum.

[cthandys]

Here are a couple shots after epoxy and before paint.

[Jim Ledger]

Better give it a good scuff sanding to knock all the shine off and give the paint a texture it can stick to.

Looks very nice, though.:)

[RodB]

I used Kirbys over system III epoxy glassed panels..and was told clean sanded epoxy would be fine by both Kirby and my boats designer. I used a primer for a few reasons.... the adherence is great with a good hot solvent primer, and a high build primer fills everything so nice and results in a really smooth surface. Finally, you have a nice tough barrier between the epoxy and the paint.

The primer I used was a fast drying base coat: #1640 Overlay from Parker Paint by Great Northwest Paint (interior/exterior Alkyd flat primer finish). . . which sands beautifully, and is thinned with Xylol (Xylene) and adheres very well to epoxy (seems not to be affected by any lingering ammines). This is a great primer for both alkyd enamels or polyurathanes and was recommended to me by Tracy Obrien, designer and boatbuilder
( tracyobrien.com). He has used it on scores of boats over the years and highly recommends it. He recommends slathering a couple of coats of this primer on with a brush PDQ, and then sands to a beautiful finish being careful not to burn through.

Tracy also commented he always felt a barrier coat of primer over epoxy insured no paint drying problems due to epoxy ammines... especially in situations where you do not have a long period of time between final epoxy application and paint application. If there is a reasonable time since the epoxy is applied... then the epoxy is absolutely cured..and if you do the ammonia/water wipe followed by a clean water wipe..then sand for some tooth... you will most likely not have any adhesion problems with any alkyd enamel or single part polyurathanes. The resulting clean inert epoxy surface is very unlikely to have any adhesion problems.

The advantages of the primer may not warrant its use for some folks... I just like the extra protection, the ease of sanding to a beautiful finish in prepping... and the barrier between the paint and the epoxy.

Good luck

RodB

[SawmillBrook]

I just applied Kirby's grey/green (exterior) and Kirby's bronze green (interior).

I applied directly over a flat enamel. I will try to post a pic tomorrow after I get it out of the garage and into the sun to bake.

So stay tuned.

Andrew