Spraying or rolling gelcoat?!

[Billythepokerkid]

Re: Spraying or rolling gelcoat?!

The sides and gunwales. The deck doesn't matter since I plan on adding sand or some other non-skid to it. I bought a gun from Harbor Freight, but my air compressor is right on the edge CFM wise, so I am thinking I will just roll as much as I can and spray the corners and such where I can't get a roller into. I did a couple tests on some plywood, just to see what it would be like and the finish with the roll and the gun aren't that much different. A paint brush just seems absolutely impossible to use.

 

[Yacht Dr.]

Re: Spraying or rolling gelcoat?!

The sides and gunwales. The deck doesn't matter since I plan on adding sand or some other non-skid to it. I bought a gun from Harbor Freight, but my air compressor is right on the edge CFM wise, so I am thinking I will just roll as much as I can and spray the corners and such where I can't get a roller into. I did a couple tests on some plywood, just to see what it would be like and the finish with the roll and the gun aren't that much different. A paint brush just seems absolutely impossible to use.

Just plywood ? With Gelcoat ..on plywood ..not glassed ply..but plywood..

So your going to roll out gel on the sides and gunnies .. and roll is the same as your gun? Did you thin it out for your gun..if so..what did you thin it with. ?

I dont mean to be so questionable .. but your not really giving any responses back to our suggestions. And some of your statements are questionable as we have done these things before.

YD.

 

[Billythepokerkid]

Re: Spraying or rolling gelcoat?!

I patched and glassed the deck, so there is no plywood. The gel is going on the existing gelcoat and bare fiberglass. The gel coat out of the gun was thinned with less than 10% MEK, then sprayed. I let that dry for a bit, then mixed up a small batch of gelcoat and rolled an area right next to the area I sprayed previous with a 3 inch roller, just to see the difference. The roll left a bit more texture, but it didn't have that orange peel look that the sprayed area did, so both would have to be sanded, so in my estimation, 3 coats either rolling or spraying will yield a fairly similar thickness. After sanding/buffing there would be no difference between the two areas. Once I start spraying, if it goes well I may just spray the whole thing. My only concern is having to wait for my compressor to catch up will make using the gun exclusively not a possibility, since the gelcoat will most certainly begin clogging the gun before I get done, unless I mix smaller amount of gel and buy stock in some Acetone company.

 

[Woodonglass]

Re: Spraying or rolling gelcoat?!

The gun I recommended was for painting NOT Gelcoating. Gelcoating requires a totally different setup. A minimum of a 2.5 mm tip (your gun has a 1.4 mm tip, which is WAY to small) A minimum of a 3 hp 60 gallon compressor. Gel coat ALWAYS orange peels and requires sanding. Gel coat will begin to gel and setup in approx. 15 - 20 mins and therefore you MUST stop and completely clean your gun or you will ruin it. To be effective it should be applied to about the thickness of a "Penny" or 2 mils thick. Now...I am NOT a Gelcoater, what I've just told you, I have learned here on the forum from guys like, YD, Ondarvr, and OOPS from Reading and studying their Threads and posts. I just try to pass it along to the next guy.

 

[Billythepokerkid]

Re: Spraying or rolling gelcoat?!

I didn't buy that gun. I bought a different gun. I also found a 3 mm tip that I used. My compressor, runs right under the recommended CFM for the gun, so I just turned the psi down a tick and it seems fine. The compressor kicks on after about 25 seconds of continuous spray. I sprayed about 16 oz, or 1/2 quart in about 3.5 minutes, so I just had to wait for the compressor to catch up a few times, which is no big deal, but to spray an entire quart at once might be cutting it close. I estimate it will take a little over a gallon to spray what I need to spray. So I would probably have to buy 3 gallons of Acetone. Which in essence is about what it would cost to buy the enamel and primer you were talking about. So I am gonna debate the next few days and whatever I decide will go down this weekend.