Attempt to restore gelcoat

woodster · May 4, 2015

sail_MN said:
Last week I went up to the boat with hopes of restoring my chalky white gelcoat. I have read Mainsails article over and over and followed his procedure step by step. So far here is what I have done...

1. Washed hull using an acid based cleaner

2. Wet sanded using 600 grit then 1000 grit.

3. Compounded using Makita 9227 buffer.

So far after spending 3 days on a 28 ft. boat I am still trying to get past the compounding stage. While I was wet sanding, the boats gelcoat looked absolutely beautiful. Once dried of course the dull came back. The problem I am having is with the compounding stage. I am working in 2ft by 2ft. sections. The wool pad I am using seems to get plugged up and dried out way too fast. I find myself having to take the pad off and clean it every few minutes. This seems quite excessive. Is it normal for the pad to be full of dried on compound after every 2x2 section? Should I have wiped the hull down with anything special? I am also having a hard time keeping a consistent shine going down the side of the hull. When I move on to the next section, my buffer wants to sling a little residue back on what I just finished and kind of gives it a blotchy appearance when looking down the hull. If anybody has experienced this and know what I am doing wrong please let me know.

P.S. I was amazed by how many friendly people at the boat yard stopped by and offered up advice with their favorite one step magical products.

go back and read maines article again ...i didn't read where you were using a foam pad to compound with ...that may be your problem and get a spray bottle of water and use it while buffing with the compound and you will have to clean the foam pad from time to time but not every 2 sq feet

Charles Erwin · May 4, 2015

Did you wet sand at 1000 stage? What compound are you using to follow 1000 sanding stage?

If your 1000 was done wet (misted), your compound is aggressive, and you are using a white wool pad (you need that compounding combination to erase a 1000 scratch) it sounds like too much compound and/or you have not wiped off the residue. Use a new micro fiber cloth and retire them (wash w/ no fabric softener) at probably 2 cloths per side.

About a quarter size dollop of compound per 2 - 3 sq ft. Also use a water spritzer bottle thus to keep the area moist. You should be getting very consistent and shiny results at this stage.

I favor 1000 wet followed by 3M Trizact P1500 misted on a R/O sander with an interface pad (a soft spongy pad between the sander and the Trizact disc) before compounding - sometimes even P3000 Trizact before compound. That way you are polishing more that flatening. And - it is much easier to erase a 1500 - 3000 scratch than it is to erase a 1000 scratch.

In any case reduce the compound amount, keep the area wiped down with a clean micro fiber towel, and use a bit more misting.

Charles

PS Thank the neighbors for their thoughts however the magic one steps just don't make it

njlarry · May 4, 2015

Yes sounds like you may not be misting the pad with water enough? Also hope you are using a white wool componding pad to be followed by a yellow wool polishing pad. I clean the wool pads by holding a large tongue depressor against the spinning pad.
Must be frustrating but hang in there. Once you figure it out the effort will be worth it. As my neighbor on the hard at the marina pointed out while we were all slaving on our boats this past weekend..."It's a learning experience."

Stu Jackson · May 4, 2015

Are you following MS's instructions to the letter?

sailnoproblem · May 5, 2015

Gelcoat compound

Stu Jackson said:
Are you following MS's instructions to the letter?

I agree with Charles and njlarry. What compound are you using? I had the similar problem and used 3M gelcoat compound sold at West Marine, a wool pad on a high speed grinder (be careful) kept the compound wet and took my time. Small section at a time. Don't forget to keep the pad clean. I used a mixing stick.
When I started it took over a month, starting with wet sanding through compound and wax. I had great results. The hull was extremely chalky and I wasn't really sure of the hulls original color.

woodster · May 5, 2015

sorry about the incorrect statement about the foam pad just went back and looked again my self had to drink my own bath water lol ...here is the short version of mains instructions

Buff Polish & Wax

Try these products (for Gel-Coat only not intended for Awlgrip)

The Cliff Note Version:
Steps:
#1-Clean the hull with an acid base cleaner like FSR, oxalic acid or On & Off to remove rust & tannin staining. (only if necessary)

#2-Wet Sand by hand 600 (if real bad) then move up the grits to P1000+ (only if severely oxidized other wise you can start at #3)

#3-3M Marine Rubbing Compound or Presta Gel Coat Compound (use a wool 3M super buff COMPOUND grade pad like the #05711) (if already fairly shiny start at #4)

#4-3M Finesse It or Presta Ultra Cutting Creme (Use a foam 3M #05725 pad or 3M Yellow Wool # 05713 Note: Yellow wool is far easier and far more forgiving for a novice and will also last a LOT longer than any foam)

#5-(OPTIONAL STEP) Presta Chroma - Use 3M #05725 foam, #05713 wool or Blue Presta wool pad.

#6-Collinite #885 Fleet Wax Paste Version- or 3M Performance Paste Wax. For a polymer coating I like AwlCare or Nu-Finish

Scott T-Bird · May 5, 2015

Why the need to clean the pad?

By all means, make sure you have the right wool pad for compounding, the white wool pad like everybody says.

Why the need to repetitively clean the pad? I don't clean the pad until I'm done with the boat. By the time you compound, the boat should be plenty clean, although be sure to protect the pad from bottom paint. The pad should be moist as you start compounding, but I see no reason why to keep cleaning the compound off. You are just putting more back on the pad.

I use more than a quarter-sized dollop. I criss-cross the pad with compound and make sure there is plenty on the pad. Misting the surface of the gel coat is key. I let it dry while I'm working so that I'm just finishing the section as the compound is just barely dried out. Then I wipe the residue with a clean terry cloth towel before a finish wipe-down with micro-fiber. I always want the residue to be just slightly moist as it builds on the terry cloth. Have to keep using a clean section of towel for each section. I think 2' by 2' is too small and tedious. I do the entire height of the topside for a width of about 3' for each section so it is more like 3' wide by about 4' tall (or more).

It works best if the day is not too hot and sunny. A cloudy day is best because it is easier to time your work so the compound doesn't dry out too fast. Sun directly on the surface makes it harder to do a good job.

I like the 3M compound but I've never been able to get good results with 3M Finesse-it. So I switched to a Meguiars polishing product last year, which was better. I couldn't get the Finesse-it to provide the mirror-like finish that I would have after compounding, it always came out more dull, which was baffling to me. Last year, with Meguiars, the finish came out looking about the same as after compounding, so I wasn't unhappy at least. I still haven't figured out the polishing step, yet.

My finish is still good this year so I'm just cleaning and polishing, before wax. Obviously, late this year ...

DHaranSailor · May 5, 2015

woodster said:
sorry about the incorrect statement about the foam pad just went back and looked again my self had to drink my own bath water lol ...

Not sure if this is you saying you are using a wool pad and are just now realizing it should be the foam pad or if you just misstated your first post. If it is the former then switching to the pad will make a world of difference.

Went through this processes last year on a O'Day 22. I had the best results when I stuck to the small 2' by 2' sections and like mentioned above I did a X on my foam each time I started a new section to make sure it was distributed evenly.

Good Luck!

woodster · May 5, 2015

based on the short version of maines instructions it says use a wool pad but i have used foam with good results and i think main uses foam in his work but for the novice i think he recommends wool pad as it is less aggressive

sesmith · May 5, 2015

I think Charles Erwin pretty much nailed it. After wet sanding with 1000, I usually step it up to 1400 grit and even 1500 grit. Wet sanded to that level makes buffing much easier. A product like Presta cutting cream and the matching pad (presta black pad) will put a nice shine on it from there. Too much compound on the pad will just make a mess. Follow the directions on the Presta bottle (dollar sized blob). If necessary, mist with a little water, but be careful how much of that you use, as it can gunk up the pad if you overdo it (especially if you use too much compound).

JRacer · May 5, 2015

Check out www.autogeek.net and look at some of their videos re: cutting and polishing. I use their CCS foam pads with my porter cable dual action buffer. Because of their textured design they tend not to accumulate compounds and waxes. They do wear out so you will need more than one of the various types (aggressiveness). I also use "aqua-Buff" 1000 and 2000 (google it) compounds which I think work better than the stuff you get at the auto parts store.

Apex · May 6, 2015

only variation from MS post a fellow boater shared was in the compounding and cutting crème was to use less water. The presta products are breaking down to finer grit as they go.

MS hopefully can comment: putting small amount on wool pad, spreading that out without turning the buffer on over the 2x2 area, then buffing with the machine over the area until the compound is dried and buffed off. Results look good, so hopefully it is an adequate technique. For the polishing phase, there was better results in keeping the area wet until a thin dried film was left, and the foam pad then was used to continue buffing it dry and clean.

down_shift · May 6, 2015

I also followed MS's steps just last month but 1) did not introduce any water during the compounding or polishing and 2) cleaned the pad w/a wood stick after completing each section (4'w x 1/2 hull height). Here is the before and after. I'm still clicking my heals with pride seeing the water reflect off the hull. Before there was nothing. Bonus was the hull stripes came back as well. Now it is time to tackle that 28-yr old neglected deck. The rub rail will be replaced afterwards.

Ward H · May 6, 2015

I followed Main's instructions to the letter when I got my boat and it came out great.
I admit I just skimmed some of these posts and I'm probably repeating what others said but here are my learings:
1. Follow the instructions to the letter. The only step I skipped was the acid wash.
2. Use plenty of water when wet sanding, compounding and polishing. Once any of those steps get dry, it won't work.
3. Use the correct wool pads.
4. Follow the instructions to the letter.

Attempt to restore gelcoat

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