Gelcoat or paint?

[dhillis]

I am in the process of making the boat in my signature look good again. I am 90% done sanding the hull. I am having a hard time deciding to paint or gel coat.

Some specifics that may help with your advice: boat has original gel coat and my sanding has found some low spots, there are a lot of small gouges and such that need filled (which I am doing as I sand and find them), some of the gouges are quite large and needed a lot of filler.

I'm having a hard time color matching all the gouges to make it look decent. Painting or gel coating seems to be my only solution to a uniform look. I have the supplies to paint or gel coat (ie., spray gun, compressor, insulated shop with heat for whatever temps I need for a good job, etc...). The only real problem is my budget, as if you haven't heard that before. From what I have read, gel coat seems to be less expensive, but more difficult. However, I do want a finish that will last a long time. It should also be noted that the boat is trailered always.

Thanks in advance,
Dan

 

[dhillis]

Re: Gelcoat or paint?

I forgot to mention something. I will be unable to flip the boat for the painting/gelcoating process. Will this make it difficult to prevent sagging, dripping, etc? I am most concerned about spraying the bottom of the boat since it can't be flipped.

Thanks,
Dan

 

[ondarvr]

Re: Gelcoat or paint?

The cost of gel coating looks like it's less up front, but check out the cost of good sand paper and the time involved.

If you want it to have that original look, then you need to use gel coat, but painting is much easier.

 

[dhillis]

Re: Gelcoat or paint?

Well the sanding isn't much of a big deal to me, heck I already sanded the entire boat once anyway. I'm more concerned with durability, low maintenance and cost.

I'm going to be building a custom swim platform and I already have a can of gel coat laying around, so I will spray that and see what happens.

Thanks ondarvr for the reply.

Dan

 

[Yacht Dr.]

Re: Gelcoat or paint?

aye..Gel it..

find what gel your gonna spray before you fill...use that same gel mixed with cabosil to fill..

then spray.

I know it seems hard..and sometimes it can be..but once the spray is done ( 2 hours ) its all sand and buff..no dirt..no prime,sand,mask again,spray..oh crap dirt..oh crap etc.. just spray and spray..and sand and buff..

Gel is the way m8..

YD.

 

[dhillis]

Re: Gelcoat or paint?

YD, I asked this in my second post: "I will be unable to flip the boat for the painting/gelcoating process. Will this make it difficult to prevent sagging, dripping, etc? I am most concerned about spraying the bottom of the boat since it can't be flipped."

What's your opinion on that?

Dan

 

[dhillis]

Re: Gelcoat or paint?

Well, I bought the gel coat and was practicing on cardboard without the hardener to get the right spray. It seems that unless my pattern is a very small oval, the gel is spattering when sprayed. I have adjusted the heck out of the gun, a HVLP gravity feed, to no avail. When I clean it out, I pour laquer thinner in the cup and spray it through the gun and it sprays a very nice, wide pattern. Because of that, I believe the gel is not reduced enough.

Notes on gel: 200cc gel, 50cc acetone (reduced 25%)

Gun settings: 45 PSI at regulator, but can be varied. pattern adjustment knob practically turned off to get good spray (smallest pattern), fluid control knob turned out for maximum feed, air volume control knob turned out for maximum pressure, air nozzle horizontal for vertical fan spray.

Any suggestions?

Thanks,
Dan

 

[ondarvr]

Re: Gelcoat or paint?

This is one of the many issues you will run into when refinishing with gel coat. It is designed and formulated for use in a mold, not post coat type applications, it just happens to work "most" of the time when used this way though. Normally a re-gel coat surface will not hold up as well as the original mold surface even when done correctly, this is more noticable on colors.

There are products you can add to gel coat for a better spray pattern and leveling, but they can interfere with cure, water and weather resistance.
While small (10% or less) amounts of acetone normally do no harm, 25% may and depending on the type of gel coat and the temperature, still may not give the desired results. Patchaid type products are what's recommended and can be found at places that specialize in fiberglass supplies, they will also help the gel coat cure in the thin film that will be applied.

That uneven surface is why it can be so much more time consuming and sometimes costly to re-gel coat than paint. You will need to sand down the entire hull with a few different grits of sand paper to remove the orange peel surface and if you can't flip the boat, it means you will be laying on your back under it for many hours. Doing a small repair is not big problem, but doing an entire hull and/or deck can be.

For an experianced professional with all the correct tools and equipment, it can be done well, but there are still things that can and do go wrong resulting in it needing to be redone. That's why I normally recommend painting for the typical boat owner that just wants to make his old boat look respectable again. Gel coat and paint do have a different look though, so if you want that original gel coat look you need to use it.

 

[dhillis]

Re: Gelcoat or paint?

ondarvr,

Do you sell paint or have stock in paint? I don't mean to be a smart *ss, but I've already heard the comparisons between paint and gelcoat. I am now gelcoating and that's the way it's going to be. I would like some useful information about setting up an hvlp for gelcoat, not why I should use paint instead. I am well aware of the orange peel, sanding, buffing, polishing with gelcoat and I am ok with that.

Anyone else with useful information is very welcome to respond. ondarvr, this was not a personal attack, but I do want gelcoat information, not paint.

Thanks,
Dan

 

[sdunt]

Re: Gelcoat or paint?

Here some notes I have collected about spraying gelcoat, I have NOT done this personaly, this is what other people have reported:

Spraying Gelcoat

The mix for 25 sq ft coverage was:

14 cc Mineral Spirits
30 cc Wax S10
40 cc Acetone
1 qt Gel-Coat
9 cc Catalyst


For cleaning the surface before spraying we used MEK.

Shooting gel - so far it has been a breeze. I am using 4oz acetone/quart gel to thin the gel...I am mixing everything except the hardener in a mixing cup first...getting the color to where I am happy...then pouring it into the sprayer cup...adding hardener and shooting. It took alittle playing with the adjustments to get it to spray how I wanted it. I am very impressed with the outcome so far

 

[Tail_Gunner]

Re: Gelcoat or paint?

ondarvr,

Do you sell paint or have stock in paint? I don't mean to be a smart *ss, but I've already heard the comparisons between paint and gelcoat. I am now gelcoating and that's the way it's going to be. I would like some useful information about setting up an hvlp for gelcoat, not why I should use paint instead. I am well aware of the orange peel, sanding, buffing, polishing with gelcoat and I am ok with that.

Anyone else with useful information is very welcome to respond. ondarvr, this was not a personal attack, but I do want gelcoat information, not paint.

Thanks,
Dan

He sell's gel for a living, you might want to pay close attention to what he as to say, so far after watching his post's for 2 year's he's been spot on and consistent in almost every aspect of resin's

 

[ondarvr]

Re: Gelcoat or paint?

As Tail Gunner said, I do sales and tech service for gel coat and resin, that's why I gave you information on the correct products to use when re-gel coating. I don't just give information on how to use these products to DIYers, I have worked with most of the major boat builders in North America doing training classes, intruction and audits on how to correctly use resin and gel coat to get the best results. At one Gel coat company I was in charge of the marine industry in North America, now I work for the largest gel coat company in the world, so the information I give has been well researched.

There is no miracle product that will create a great surface and not compromise the weather ability of the gel coat. If the gun you have doesn't have the correct tip, nozzle and needle then you won't get the best fan, for Binks a 66 or 67 will work. To respray an entire hull with a gravity feed or siphon gun will be very difficult, they just don't flow enough material to do large sufaces, a pressure pot will work much better (very cheap at Harbor Freight) and you will need to spray the gel coat about 20 mils thick for it to cure properly. It will also be hard to spray up at the angle needed to do the bottom of the boat with the gun you have if you can't turn the boat over.

Another method is to rent an airless paint sprayer, the type you would use to do your house and use an 18- 50* tip. You can run into big problems if you don't work fast enough and the gun sets up, or if the solvent you use eats the seals, but it's fast and will do a good job. I don't officially recommend this method though.

 

[dhillis]

Re: Gelcoat or paint?

sdunt, thanks for the info, I too have gathered that from searching gelcoat threads.

ondarvr, I respect your position and admire the knowledge you must have, but can't give to me... I surely with I knew. On another note, my practice has been limited to about 20 minutes of spraying gelcoat, so I am taking into consideration that there will be a learning curve. I have talked to a few local, well respected gelcoat techs today and they have given me a good bit of insight into the mysterious world of gelcoating. When I find time, I will apply these techniques and let everyone know what I've learned.

Thanks for all the help,
Dan

 

[Yacht Dr.]

Re: Gelcoat or paint?

YD, I asked this in my second post: "I will be unable to flip the boat for the painting/gelcoating process. Will this make it difficult to prevent sagging, dripping, etc? I am most concerned about spraying the bottom of the boat since it can't be flipped."

What's your opinion on that?

Dan

2qt pressure pot...sand 40-80g..spray gel....once kicked spraypaint it for guide coat..sand till 600-800g machine...buff..that ez..

like i said..if you want to prep for primer..then sand up to 400G then paint..with no dust.. your nuts..gel it.. buff it..sand and buff till perfection

PS. gel is Not for molds..exlusively..you can full spray with no probs..


YD.

 

[dhillis]

Re: Gelcoat or paint?

Thanks YD, I like a challenge anyway! When practicing with spraying gel before, I was running 45PSI at the regulator. The gun manual states that as maximum pressure. Would it hurt to turn up the PSI to get better spray for the thicker gel coat?

Thanks,
Dan

 

[drewpster]

Re: Gelcoat or paint?

I found this gun on a fiberglass supply website. I was wondering if anyone here has ever used one? Is it used like a conventional gun?

 

[studlymandingo]

Re: Gelcoat or paint?

Another method is to rent an airless paint sprayer, the type you would use to do your house and use an 18- 50* tip. You can run into big problems if you don't work fast enough and the gun sets up, or if the solvent you use eats the seals, but it's fast and will do a good job. I don't officially recommend this method though.

I own an airless. I recently sprayed a fiberglass pool at a rental house I own; I rented a sprayer from the "Depot". Why rent one when I already own one you ask??? I really like my airless and don't want to run a two-part through it for precisely the reasons you mentioned!!!​

 

[ondarvr]

Re: Gelcoat or paint?

YD

Yes gel coats are designed for in mold Mold use, virtually zero R&D goes into using them in post coat situtations with the exception of doing small repairs. They just happen to work when sprayed on a surface then sanded and buffed. If they were designed to be used like paints, then they would be formulated to spray, level and flow much better than they do. 99+% of gel coat is used for in mold use, thats why little or no R&D is done for post coat applications, but like I said before, it does work most of the time.

drewpster
That type of gun will spray gel coat, but tends to have very large droplets that don't level well, leaving a very rough surface.

dhillis
It seems I've answered most of the questions you've asked, like what to thin it with and how much to add, the type of spray gun to use, the thickenss to spray it, a couple of options on equipment and what to expect during the job. Remember you asked for opinions, I and most others in the industry prefer painting in this situation, but that doesn't mean it's the only right way to do it. I also said if you want the look of gel coat then that's what you need to use. So please don't get upset when the answers aren't exactly what you want to hear. YD has given some good information too, but tends to over simplify the job.

maybe like others, I should've just said, gel it, sand it, buff it.

 

[dhillis]

Re: Gelcoat or paint?

ondarvr, I apologize for being confrontational about the issues with spraying gelcoat. The most important reason for gelcoating this boat is for the ease of repair down the road. I appreciate all the advice you have given me about how to set things up for a good finish, at this point it is a matter of me applying what I have gathered. I do appreciate everyone's opinion and welcome them all. However, when I ask a direct question, I would like a direct answer rather than a statement criticizing the idea. I know you are doing it for my own good, but I guess I am stubborn that way. If this gelcoat job comes with blood, sweat and tears then it's just an ordinary day for me!

Again, I appreciate everyone's info and opinions and will do all I can for a positive outcome. I will definitely update this thread with pictures of my progress when I have time to really dig in and get this done.

Thanks,
Dan

 

[Bondo]

Re: Gelcoat or paint?

However, when I ask a direct question, I would like a direct answer rather than a statement criticizing the idea.
Gelcoat or paint?
The most important reason for gelcoating this boat is for the ease of repair down the road.

Paint IS the Best Answer..........

This is Another Typical thread where the poster Asks a Question,......
And,......
When the Right Answer doesn't match the poster's expectations,.......
It's the Expert who's Wrong........