Wet sand/polish or PAINT old gelcoat?

stephentyler20

Petty Officer 2nd Class
Joined
Apr 13, 2008
Messages
117
I've posted on this before, and the problem continues to nag me. Since I've had my '88 wellcraft with red hull, the chalky, splotchy, unevenly-faded gelcoat has been the bane of my existence. I spent hours (and probably damaged discs in my back) trying to wet sand, compound, and polish, and the best I ever got was *temporary* improvement in SOME areas of the boat... other areas remain chalky/faded.

I've gotten the rest of the boat beautified to my liking (i.e., the interior). The white parts of the boat (i.e., above the rubrail) are in decent shape and they polish up nicely. But the red, under the rubrail, continues to look atrocious!

So I have 2 options:
1. Try wet sanding, compounding, polishing, again. This just seems futile. I worked my *** off doing this a couple years ago, and the improvement was marginal. Was I doing it wrong? Maybe, I don't know. But I sanded a LOT. It's also really hard to track progress doing that... it's slow and painful, and I can't tell whether I've sanded enough or too much.

2. Paint. Now, I've done some research here. From what I can tell, Interlux Toplac would be a good way to go, using roll and tip. Again from what I can tell, the work would be 1. clean 2. dry sand 220 (DA sander) to rough up the gel coat, 3. primer 4. paint (sanding between the 2-3 coats).

Frankly, prep/paint sounds like less work with more predictable results. Do others agree?

The other problem, however, is cost. I'm on a pretty limited budget here, and I don't know how much this would cost me. A qt of Toplac is about $40, but I have no idea how much paint I'd need, not to mention primer, acetone, supplies... I'm sure it adds up.

Thoughts/tips appreciated!
 

Woodonglass

Supreme Mariner
Joined
Dec 29, 2009
Messages
25,924
Re: Wet sand/polish or PAINT old gelcoat?

Check Out Pettit EasyPoxy. Lot's of guys using it on here with GREAT results. Roll on Some tip some don't. Pettit undercoater for primer. Two Quarts of each should do it. Cost is about $100.00 for 4 quarts from WholesaleMarine.com.

Check out this post for this guys results with Easypoxy on his hull.
http://forums.iboats.com/showthread.php?t=365820

Good Luck and don't give up!:)
 

stephentyler20

Petty Officer 2nd Class
Joined
Apr 13, 2008
Messages
117
Re: Wet sand/polish or PAINT old gelcoat?

Thanks for the tip! I hadn't heard of that one. I'll keep them in mind, however, I'm generally reading that Toplac gets better reviews (just from some Googe searching). I'll continue to research.

I clicked your link, but it takes me to the very beginning of that gigantic thread - don't want to spend hours trying to find where he actually uses the paint!
 

skargo

Banned
Joined
Sep 14, 2008
Messages
4,640
Re: Wet sand/polish or PAINT old gelcoat?

Try Vaseline first, $2 and a little time. ;)
 

Bob_VT

Moderator & Unofficial iBoats Historian
Staff member
Joined
May 19, 2001
Messages
26,019
Re: Wet sand/polish or PAINT old gelcoat?

Try Vaseline first, $2 and a little time. ;)

+1 absolutely

Do the vaseline before you invest more $$$$$$$
 

ondarvr

Supreme Mariner
Joined
Apr 6, 2005
Messages
11,527
Re: Wet sand/polish or PAINT old gelcoat?

Try all other methods before painting.

Sand and buff a small area (1'X1') until you either get the desired results, or know its hopeless.

I see too many people do a half hearted attempt at sanding the entire boat before doing a test patch to find a method that works. The biggest problem is that you need to remove ALL of the aged gel coat or the surface will look bad again as soon as the oils and waxes from the compound evaporates. It can be very discouraging when you think you've finished and it all looks good, but soon begins to fade back to nasty.

Since we don't have a pic to know how much area is red, or what the surface contour is like, I would first recommend a DA to dry sand the surface with 600, or possibly even 400 grit. Take the surface down and then buff, see what it looks like. Again this is just 1'X1' area. Surface contour can make it more difficult to use a DA, but you should be able to do 95% of it.

Dry sanding will not cut as fast as wet sanding and the scratches from each grit will be less, so you can use coarser paper dry sanding with a DA.
 

stephentyler20

Petty Officer 2nd Class
Joined
Apr 13, 2008
Messages
117
Re: Wet sand/polish or PAINT old gelcoat?

Ondarvr,

I appreciate your thoughts. It never occurred to me to try dry sanding with a DA, but isn't that supposed to be pretty dangerous since you can cut through the gelcoat entirely? That makes me a little nervous! That said, ill gladly try it - I'd much rather do a confident sand and restore than paint.

So would the process be;
- dry sand with DA 400/600 grit
- compound
- polish?

As long as you tjink I can do this safely I'd be willing to give it a go.
 

ezmobee

Supreme Mariner
Joined
Mar 26, 2007
Messages
23,767

ondarvr

Supreme Mariner
Joined
Apr 6, 2005
Messages
11,527
Re: Wet sand/polish or PAINT old gelcoat?

If the gel coat is beyond saving, then sanding through in a few places won't make any difference since you'll end up painting it.

You will need to be careful on any radius, but you should be able to get the feel for it quickly. Hand sand any areas that need more care.

Always start with the finer grit and if that doesn't work go coarser.
 

drewpster

Commander
Joined
Oct 17, 2006
Messages
2,059
Re: Wet sand/polish or PAINT old gelcoat?

I had the same results you described when I tried to wet sand/ compound the hull of my little cruiser. The amount of shine was marginal and did not last. Considering the old gelcoat is more than 40 years old I was not surprised. The addage that a boat retains more value with gelcoat rather than paint is a mith in my opinion. I have never owned a boat that retained value for any reason. They all cost money rather than retain it. However on the whole, gelcoat is more desirable as a durable finish rather than paint. The trade off on older chaulked boats is that it just looks bad. I would think that sanding and compounding would be the obvious first step in attempting to bring back the finish. But when compounding fails, paint is the best option. (again, my opinion)
Those who know me here have read, and know, that I am a big believer in painting. Modern marine finishes are very durable. They are generally easy to apply and they look great. Painting also provides the option of repainting if the finish gets damaged or dull. After the initial prep and the first coats go on, subsecuent coats will not need the degree of prep that goes in to the primary layers. Also, if you do sell the boat in the future, its been my experience that a boat that looks fresh with a new finish brings more money regardless if it is gelcoat or paint.
There are those that have great results from sanding and compounding gelcoat to bring it back. Its always a good idea to try it before commiting to a paint job. But if the old gelcoat is just too far gone, paint is the way to go.
I recommend Interlux products. Toplac is a good choice. But if you are going to invest the time it may be better to go with a higher end product. Interlux's Perfection paint is a great product. It covers exceptionally well so you wont need as much as you think. Interlux also makes the claim that Perfection can hold its shine for up to 10 years. (i think 5 is bit more realistic) Interlux Brightside is also a great paint. It is a but cheaper that Perfection and has a two year life span. Keep mind that both of these are considered topside finishes and should not be used on boat bottoms that stay in the water. They can hold up rather well on trailer boats however. Another thing I like about Interlux is the fact that they design their paints to be used by novices using common painting tools. You can get a great finish without the need for special equipment.


I recommend you give the Interlux website a look and do some research before you begin. The Boat Painting Guide on their website is very useful in learning about Interlux paint application processes.
 

stephentyler20

Petty Officer 2nd Class
Joined
Apr 13, 2008
Messages
117
Re: Wet sand/polish or PAINT old gelcoat?

Thanks guys... You may be right that I haven't taken off enough gelcoat with wet sanding, but I don't know how much more I can do! I think I'll try the DA sander approach on 1x1 area first, and see how that goes. I'm NOT going crazy with this unless I'm confident I'll get good results. I did that 2 years ago, and it was more or less a waste of time. I'd rather just paint and be done with it! Not to mention, the sanding/compounding/polishing approach ain't free either. Those supplies add up quick.
 

Dzrtcj7

Petty Officer 3rd Class
Joined
Feb 15, 2010
Messages
88
Re: Wet sand/polish or PAINT old gelcoat?

I've recently sanded out and polished the very oxidized Red gelcoat on my boat. Mine was oxidized completely white in large areas on the sides of the hull. I'm not sure if I have particularly thick gel coat or not, but I was able to cut a LOT more than I expected. I was even able to aggressively block sand with 400 grit to smooth out some of the ripples in the glass without cutting through the gel. I'm by no means a professional, but you might find some useful information in my thread:

http://forums.iboats.com/showthread.php?t=374293&highlight=vindicator

As far as cost, I already had a good buffer so I spent about $40 in paper, $50 in compounds and waxes and about another $50 in buffing pads and other misc supplies. The biggest cost was TIME. On a 20' boat I was spending 2-4 hours per side, per cut. I've got about 50-60 hrs wrapped up in it so far. I could have spent far more time, as I still have some minimal sanding scratches, but I am happy with the finish.

You will find that after you cut the oxidation, odds are the Red gelcoat will still be discolored under. When I started on mine I did a test spot that was near where a vent had protected the gelcoat since new. Then I just sanded sanded until I had reached gelcoat that reasonably matched the unoxidized gelcoat. Then I basically color matched the entire rest of the hull on my first cut. Running water over where you sanded will bring out the color.
 

stephentyler20

Petty Officer 2nd Class
Joined
Apr 13, 2008
Messages
117
Re: Wet sand/polish or PAINT old gelcoat?

I've recently sanded out and polished the very oxidized Red gelcoat on my boat. Mine was oxidized completely white in large areas on the sides of the hull. I'm not sure if I have particularly thick gel coat or not, but I was able to cut a LOT more than I expected. I was even able to aggressively block sand with 400 grit to smooth out some of the ripples in the glass without cutting through the gel. I'm by no means a professional, but you might find some useful information in my thread:

http://forums.iboats.com/showthread.php?t=374293&highlight=vindicator

As far as cost, I already had a good buffer so I spent about $40 in paper, $50 in compounds and waxes and about another $50 in buffing pads and other misc supplies. The biggest cost was TIME. On a 20' boat I was spending 2-4 hours per side, per cut. I've got about 50-60 hrs wrapped up in it so far. I could have spent far more time, as I still have some minimal sanding scratches, but I am happy with the finish.

You will find that after you cut the oxidation, odds are the Red gelcoat will still be discolored under. When I started on mine I did a test spot that was near where a vent had protected the gelcoat since new. Then I just sanded sanded until I had reached gelcoat that reasonably matched the unoxidized gelcoat. Then I basically color matched the entire rest of the hull on my first cut. Running water over where you sanded will bring out the color.

Thanks for this reply!! Your boat looks amazing... Nice work.

So if I'm reading correctly, you WET sanded the gelcoat, correct? Did you do it by hand, or using a DA sander? I'm really thinking I'll need a DA sander this go around if I'm going to do this, and I may just do it dry.

I can't really tell from your pictures, but I'd argue my boat is more heavily oxidized than yours was. Even if I get the color restored for a period of time, it oxidizes back to whitish pink in no time. But I'll give it another go!
 

Dzrtcj7

Petty Officer 3rd Class
Joined
Feb 15, 2010
Messages
88
Re: Wet sand/polish or PAINT old gelcoat?

Thanks for this reply!! Your boat looks amazing... Nice work.

So if I'm reading correctly, you WET sanded the gelcoat, correct? Did you do it by hand, or using a DA sander? I'm really thinking I'll need a DA sander this go around if I'm going to do this, and I may just do it dry.

I can't really tell from your pictures, but I'd argue my boat is more heavily oxidized than yours was. Even if I get the color restored for a period of time, it oxidizes back to whitish pink in no time. But I'll give it another go!

Thank you!

That is correct, I WET sanded. I did it all by hand. I used a Meguiar's foam sanding backing pad to help prevent finger marks. Even with the 400 grit I had to rub A LOT, and change the paper A LOT. On the first cut, when the paper is getting heavily loaded with the oxidation I would use a 1/3 sheet of sanding paper for about a 3'x3' or less area. You'll know when you are getting to virgin gelcoat when the sanding dust turns pink. If yours is like mine, it will seem like you sand forever only getting whitish/ yellow grit. I recommend wet sanding as well because the water on the surface lets you keep track of the change in color much better as you get down to good gel.

I would probably only use a DA if I was ruffing it up to paint. I have heard of people dry sanding, but you should go clear up to like 2500 grit before you buff. I've never done it that way, so I can't say for sure.

Before sanding out my boat I could buff out a spot in the oxidation and get it to look nice and shiny, but as soon as the oils from the wax baked out, it went right back to the oxidized look.

I truly hope you are successful. Like I said, try a small spot, preferably right next to somewhere that has virgin gelcoat (hull number stickers, vents, swim platform). In that spot I would go through all the motions, clear up to buffing so you can get a feel for how much sanding you'll have to do with each grit to get the desired shine. You'll only see if you lacked sanding more when you buff it out. If you have any questions, please feel free to ask here or PM me.

Good Luck! Post pictures!
 

stephentyler20

Petty Officer 2nd Class
Joined
Apr 13, 2008
Messages
117
Re: Wet sand/polish or PAINT old gelcoat?

The problem I had with wet sanding is that as soon as the red gets wet, the color pops back out quite nicely (until it dries again). So while I'm sanding, it looks fine... and then I dry it, compound, polish, etc. and it looks like crap.

Also, I was definitely getting a pink oxidation coming off in the water when last I attempted this, but still with only modest results.

Can you please list all the steps you took when doing your boat, including prep/finish? I want to make sure I'm not skipping anything.
 

Dzrtcj7

Petty Officer 3rd Class
Joined
Feb 15, 2010
Messages
88
Re: Wet sand/polish or PAINT old gelcoat?

Yeah, no problem.

I established my steps with a trial run in a 1'x1' spot that was next to an area of gelcoat that had never been exposed to the sun to try and match color and sheen. In that spot, I started at 800 grit paper and worked my way DOWN until I found a paper that would reasonably cut throught the oxidation and discolored gelcoat. I suggest you do the same and only go as coarse as you NEED. The coarser the paper, the more work it is going to take with the finer papers to get the sanding scratches out. Most people will NOT reccomend going down to 400 grit because it is VERY hard to get all of the sanding scratches out. I had to go to that coarse of paper and decided I would live with minimal sanding scratches. In high visiblity areas such as the bow and above the rub rail I spent extra time to try and eliminate the scratches. Coming from a concours show car back ground, I feel the scratches i have are minimal and are perfectly acceptable for a 1989 boat. Most people would never notice them, but I am kind of particular about those things.

After some trial and error, here are the steps I used:

1. Wash boat with water and dish soap (dish soap does not contain WAXES like some car wash soaps do). I also removed all removable hardware here.

2. Wet sand with 400 grit paper (I had to make 3-4 passes over each side of the hull for this step to get even color).

3. Wash entire boat with just water and micro fiber mit.

4. Wet sand with 600 grit paper (I sanded stern to bow, then bow to stern. Then made one extra pass on the top decks).

5. Wash entire boat with just water and micro fiber mit.

6. Wet sand with 800 grit paper (Same process as previous step).

7. Wash entire boat with just water and micro fiber mit.

8. Wet sand with 1000 grit paper (Same process as previous step).

9. Wash entire boat with just water and micro fiber mit.

10. Wet sand high visiblity areas with 1500 grit paper (top portion of boat, most of the hull above the rub rail, particularly flat areas). At this step the gelcoat will still look fairly dull.

11. Wash entire boat with just water and micro fiber mit.

12. Make first cut (buff) with a Milwaukee Polisher 9" 1750 RPM, using a Velcro backed Wool buffing pad with Meguiars Diamond Cut compound.

** At this point you should have a HIGH SHEEN buffed finish. It should look like new gelcoat with some very LIGHT swirl marks if you look at in the right light. You will know where you have sanding scratches because those areas will appear somewhat dull. Go back to the finest paper needed (I would suggest 800 grit), re wet sand those areas, then work back up (1000, 1500, buff, ect). Most of the pictures you see of my boat are at THIS step.

13. (This step may not be needed) I made another cut with the Meguiars Diamond cut over the entire boat to help minimize some more imperfections I wasn't happy with.

14. Wash entire boat with just water (and dish soap if needed) and micro fiber mit. Still ... no wax is on the gelcoat at this point.

15. Buff entire boat using the Miluakee buffer, a foam vecro backed pad and Meguiars Swirl Remover. (Do as many times as nessecary to remove all swirl marks).

16. Wash entire boat with just water and micro fiber mit.

17. Using a foam hand polishing pad, apply The Wax Shop Super Glaze carnuba wax (just my personal preference. I suggest using some sort of pure carnuba wax here, not a cleaner/ wax).

18. Buff (remove) applied wax with a 8" orbital buffer using a micro fiber bonnet.

19. Repeat 17 and 18 as many times as you feel nessecary.

***Notes- When wet sanding I used a constant stream of water from the hose to wet areas as I was buffing, occasionally dipping my paper in a bucket of water with a little bit of dish soap to clean it out. Change your paper OFTEN.

***Disclaimer - I'm not a professional at finishing boats. Most of my knowledge is in auto restoration, which I have applied to buffing out my boat. These steps worked out for ME. They seem logical, but may not work out for everyone. Also, some skill is required in properly buffing and sanding.

It is reccomended to use a Gelcoat Polymer sealer as opposed to automotive type wax. I'm giving what i've done a shot for this season, and if it doesn't hold up I'll try out the Poylmer sealer.
 

PuddleJumper

Petty Officer 1st Class
Joined
Jun 6, 2005
Messages
314
Re: Wet sand/polish or PAINT old gelcoat?

I was in same situation last year with my 1990 Astro. Tried buffing wet sanding etc. I saw an ad for PoliGlow and ordered it. Very easy to use. GREAT results. Not showroom refurb but holds color shine pretty well. Sure beats back breaking buffing and WAY cheaper than painting.(IMHO) You can see a video on their website. Just google it.
 

stephentyler20

Petty Officer 2nd Class
Joined
Apr 13, 2008
Messages
117
Re: Wet sand/polish or PAINT old gelcoat?

Thanks for all the replies folks, however, I believe we are indeed going to paint. Here's why.

My co-owner (I call him "Dad") came down yesterday to the garage where I was working on the boat, and basically said, "screw it, let's just paint it." I took another walk around the hull, and fully realized that he's right, no amount of backbreaking wet sanding is going to get the shine back on this baby - it's gone. I gave it a really, really solid effort a couple seasons ago, and even small test areas are back to being completely oxidized again. I legitimately think it will be significantly less work to prep and paint the boat than to go through all that again with questionable results.

So, I believe we'll do either Toplac or Petit Easypoxy, whichever comes in cheaper probably, and do roll and tip. Even if it doesn't come out as nice as a spray on 2-part urethane, it will look 100x better than it does now, and 20x better than if I wet sanded again, I think. We're only going to do the red part of the hull (most of the freeboard) - the white on the deck and above rubrail shapes up very nicely with some polish and wax. I've already pulled all the external hardware, and tomorrow I'm going to tackle some leftover pinstriping, then its go time probably in a couple weeks!
 
Top