Paint or Gelcoat

[vvfdfirefighter]

Alright everyone....I'm having a mental debate with myself. After spending 4 days compounding, buffing and waxing my '87 Marauder I was hit on the lake by another boat. No structural damage to the fiberglass but I do have chips and scratches in the gelcoat. The shop I took it too says he'll do gelcoat but highly suggests paint since this gelcoat will be very hard to match and blend.

As I was compounding the boat I did find a spot on the starboard side of the boat that was previously fixed. it's from the rub rail to the waterline and about 3' long. Obvious hack job it looks horrible and it was painted to match the old faded and oxidized color. Now it sticks out like a sore thumb.

My whole hull is that 1980's blue. It looks amazing all buffed up and shinning. If I were to paint though I'd opt to pant the bottom white and the sides blue still.

How well does this marine paint hold up. Especially on the bottom?! Or should I save up bite the bullet and do a whole new gel coat?


This is how she looks...





This is how I'd change it



Or.

[Ptownkid]

I've heard good things about the two part polyurethane from interlux...but like all paints osmosis is a consideration. Do you leave it in the water at all?

[vvfdfirefighter]

It used to be left in the water all summer long but now that I live 2 hours from the water it's a trailer boat.

[CJD]

For abrasion resistance, the best is gel coat, then two part urethane, and finally one part urethane. Gel coat is definitely best...but boy what a pain to spray!!

[vvfdfirefighter]

Spraying isn't my biggest worry. Getting rid of the gelcoat on the boat already is. Starting fresh at the glass so I don't go too thick and developers cracks. I know you can't gelcoat over existing gel can you?! My head hurts ha

[lively]

Yes you can gel coat over gel coat , you will have to sand and all that , or you can just use base coat clear coat like I did . Really depends of how big of a area you are wanting to paint


Whoever sprays the bottom make sure they sand and acetone and layer the paint , I had to repaint my bottom but only cause it was not prepped correctly

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[CJD]

Spraying isn't my biggest worry. Getting rid of the gelcoat on the boat already is. Starting fresh at the glass so I don't go too thick and developers cracks. I know you can't gelcoat over existing gel can you?! My head hurts ha

If you're not worried about the spraying, then you haven't sprayed gel much before. Compared to paint, gel coat it a whole new level of pita. The prep must be absolutely meticulous, or you get fish eyes, waves and orange peal. It's so thick that it does not flow well. Modern urethanes are much more forgiving than gel. Try to thin it and you can get spider cracks.

[vvfdfirefighter]

If you're not worried about the spraying, then you haven't sprayed gel much before. Compared to paint, gel coat it a whole new level of pita. The prep must be absolutely meticulous, or you get fish eyes, waves and orange peal. It's so thick that it does not flow well. Modern urethanes are much more forgiving than gel. Try to thin it and you can get spider cracks.

Spraying worries me but grinding all the oem gel off worries me more I guess. Knowing I can't layer new gel over old gel.

Ie. Changing hull color to white while keeping the freeboard blue.

[CJD]

Spraying worries me but grinding all the oem gel off worries me more I guess. Knowing I can't layer new gel over old gel.

Ie. Changing hull color to white while keeping the freeboard blue.

You will need a power sander, as the job would be way to hard hand sanding. The good news is that gel is very thick, so it fills scratches well...meaning you can use a fairly coarse grit to speed things up. If the base gel is spider cracking, then it is best to take it down to the base of the original gel coat. If the original is not cracking, then it is not as important to remove all the old, just rough and thin it.

Spraying is best left to a good shop, as I have only done small gel jobs, and cannot imagine trying to spray an entire hull without the special mixing guns that only a large shop will have. It is a true art to get the catalyst mixed in the right amount for the temp. Also, gel comes without the surface wax agent to allow surface curing, so that has to be added in the correct amount before spraying.

Gel coat is definitely the hardest, most durable way to go, but check pricing to see if it is worth the extra abrasion resistence to you for the price it will cost.

[inair]

I did a fiberglass repair job to my swim deck this spring and then applied gel coat to the whole thing. It was a real learning experience. You can find out what every one else says about what you want to do but when you get started you'll find that most of what you saw and read will not work the way you/they thought. What I found is that I could easily sand through all the gel with 80 grit in the places that needed it and then finish with 120. 120 grit seems to be just right (and is recommended) for re-spraying. The things that make gel coat difficult are,

1. Gel coat is made to be sprayed onto a mold and then have the glass laid up on top of it. Which means it has to cure with out oxygen; that is, it can ONLY cure without oxygen. So after you spray on your last coat you must spray on a coat of PVA, polyvinyl alcohol, that will act as a barrier to oxygen and allow the gel to cure. If you spray PVA on too soon after you spray the gel, spraying the PVA on will deform the gel and you will have to sand it off and start over. You can also buy gel coat that has a wax added to it that is supposed to accomplish the same thing but there a lot of discussion as to whether it actually works. (check out all the boat repair forums)

2. Gel coat will not lay down or even out like paint, so you have to put it on thick enough to be able to sand out the orange peel or you will always have orange peel.

3. If you have a big job like a whole boat bottom, you will need a gun that will inject catalyst as it sprays because pot life of the pre catalyzed gel will be too short to get the job done unless you do very small sections. If you do small sections that will increase sanding time and make it more difficult to get an even layer over the whole job.

4. Instructions that are provided with what ever product you buy will be so minimal that you will have to find catalyst rates and cure times/methods from other sources. Even talking to a rep, you will find that they have never done this and may (will?) give you information that is inaccurate or contradictory to other information you already have so doing some experimentation with the product will be critical and will increase the amount of material you need and it's overall cost.

I like finished gel coat. It is beautiful, tough, and resilient. But it was designed to be used in a specific way. Working with it as a repaint or repair is a major PITA. Talking with those who have pained their boats it seems that paint would be much easier. But I don't know. I've never done it. I would also like to see what a painted boat looks like in twenty years? Some of the new paints available are supposed to be really good but without being able to really compare its hard to know.
Good luck!