PDA

View Full Version : Gelcoat scratches/cleanup



pmoomba
09-06-2011, 09:40 AM
I have a few scratches in my gelcoat I'd like to repair. I don't believe any are too deep so I'd prefer to avoid sanding at first and risk doing more harm than good. There seem to be a million products/ways to do it but I think I've narrowed it down to the Meguiar's restoration system to keep things easy. I know there are a bunch of threads and I've looked through them, just trying to settle on a shopping list since every thread I look at lists different products and more options, making it a little confusing to sort through.

Meguiar's M4965 Marine/RV Fiberglass Restoration System (http://www.amazon.com/Meguiars-M4965-Marine-Fiberglass-Restoration/dp/B0000AY4YT/ref=sr_1_1?ie=UTF8&qid=1315308769&sr=8-1) - Can I get away with one pack of this if I decide to do the whole boat, or will I need more?

Meguiar's W7006 6.5-Inch Soft Buff Foam Cutting Pad (http://www.amazon.com/Meguiars-W7006-6-5-Inch-Soft-Cutting/dp/B0002VAZA2/ref=pd_cp_hi_2) - Use with oxidation remover
Meguiar's W8006 6.5-Inch Soft Buff Foam Polishing Pad (http://www.amazon.com/Meguiars-W8006-6-5-Inch-Soft-Polishing/dp/B0002UQAXY/ref=pd_cp_hi_1) - Use with polish
Meguiar's W9006 6.5-Inch Soft Buff Foam Finishing Pad (http://www.amazon.com/Meguiars-W9006-6-5-Inch-Soft-Finishing/dp/B0002UQAY8/ref=pd_cp_hi_3) - Use with wax

Is this basically correct? Then, for a polisher/sander, is there a difference (aside from 5 bucks) between these? Are these good enough for light to medium scratches with the above products? I think these are what I usually find recommended in other threads.

Porter-Cable 7424XP 6-Inch Variable-Speed Polisher (http://www.amazon.com/Porter-Cable-7424XP-6-Inch-Variable-Speed-Polisher/dp/B002654I46/ref=pd_sim_auto_7)
vs.
Porter-Cable 7346SP 6-Inch Random Orbit Sander (http://www.amazon.com/Porter-Cable-7346SP-6-Inch-Random-Polishing/dp/B002EQ96MG/ref=sr_1_23?s=hi&ie=UTF8&qid=1315309438&sr=1-23)

Is that stuff about right or overkill/underkill?

Then, a few related questions:

- If you do the 'whole boat' instead of just problem areas/scratches, do you get underneath and do the hull? I imagine it'd be hard to work under there with the polisher, do you do the hull by hand?

- If you do the hull, do you lift the boat off the bunks? If so, how? I should at least raise the bow of my boat off the trailer as some of the scratches are up there from the previous owner, and I assume from the boat buddy. What can I rest the boat on safely to do this? I have a bunch of cinder blocks but I'm not sure what to put between the cinderblock and the boat, and where to support it from.

- What do I do about graphics? Assuming I don't want to take them off, is it safe to just pretend they're not there and use the polisher/compounds right over the graphics? Or should I avoid them entirely and do the small bits inside the graphic borders by hand?

- Do you generally need to plastic off the interior if you're doing the sides/hull, or is that only an issue if you do the deck?

Thanks

08LSV
09-06-2011, 11:36 PM
I can't provide any input on which way to go, but it would be great if you could do a "How to" when you figure it out.... I have the same light scratches in various places around the transom and would like to know what works and is the least invasive.

Thanks

hgvandy
09-07-2011, 12:45 AM
The polisher and sander are the same. I bought the sander at Lowe's and it did an amazing job. I tried the meguiar's polishing pad and compound and it just did not get the scratches out of the gel coat. After this, I ordered Lake Country Pads and used the following products and steps below. (I got this from a thread on this site)
Step 1) Wash the boat
Step 2) Claybar the surface
Step 3) Wetsand the deep scratches with 1500 grit
Step 4) 3M Marine Rubbing Compound (yellow 6.5" pad)
Step 5) 3M Marine Finess-It II (white 6.5" pad)
Step 6) Klasse High Gloss Sealant Glaze (black 6.5" pad)
The results were amazing, but it took a lot of hard work and patience. I worked an area at a time and the deeper scratches took more work, but well worth the results. I will follow this same procedure every year.
I did not bother with the belly of the boat. You do need to be careful around the wrap, but I did not have a problem by polishing lightly.
I would recommend using plastic around the inside, because splashing is an issue, especially as you go around the top and near upholstery. Hope this helps.

NCSUmoomba
09-09-2011, 01:07 PM
Lots of questions. First, I use exclusively Mequiars product on my boat, and I have used all three of these products. The oxidation remover works really well, but I don't think it will remove scratches that you can feel with a fingernail. I have not used it with a machine, only by hand.

The two machines you posted are in fact different. The polisher just spins the head, while the sander oscillates the head while spinning. It is my understanding that a polisher is what is needed. Also, it needs to have a reliable speed control. If the speed is controlled by the trigger, it is too easy to get the speed too high and burn the gelcoat. Some of the polishers have a thumb wheel to set the speed separate from the trigger. There is a maximum speed at which polishing should be done, and it varies according to the surface and what product is being used.

I ususally just do the boat sides and under the bow where I can reach. I have polished and waxed the underside of my boat with it on the trailer, but it is a total pain, so I only did it that once. If you do lift up the boat, a wood block on to of the cinder block should be okay, or you could put a piece of carpet there as well.

As far as the graphic, I usually just polish over them, but again I do it by hand. And I don't plastic off anything when I do it as I am usually cleaning the entire boat.

deafgoose
09-09-2011, 01:12 PM
The polisher and sander are the same. I bought the sander at Lowe's and it did an amazing job. I tried the meguiar's polishing pad and compound and it just did not get the scratches out of the gel coat. After this, I ordered Lake Country Pads and used the following products and steps below. (I got this from a thread on this site)
Step 1) Wash the boat
Step 2) Claybar the surface
Step 3) Wetsand the deep scratches with 1500 grit
Step 4) 3M Marine Rubbing Compound (yellow 6.5" pad)
Step 5) 3M Marine Finess-It II (white 6.5" pad)
Step 6) Klasse High Gloss Sealant Glaze (black 6.5" pad)
The results were amazing, but it took a lot of hard work and patience. I worked an area at a time and the deeper scratches took more work, but well worth the results. I will follow this same procedure every year.
I did not bother with the belly of the boat. You do need to be careful around the wrap, but I did not have a problem by polishing lightly.
I would recommend using plastic around the inside, because splashing is an issue, especially as you go around the top and near upholstery. Hope this helps.

I wrote these instructions and the only thing I would change is step6. The Klasse sucked balls.

KSmith
09-09-2011, 04:05 PM
I use the Porter Cable Dual Action Buffer/Polisher. Porter Cable 7424 XP

For a scratch of any real depth, I guess meaning you can feel it when you run your finger nail over it, I use the 2000 wet sanding, by hand, using a small rubber block to ensure no finger grooves. After the 2000 wet sanding I use Meguires 105 and a 4 inch meguire cutting pad (sort of maroon colored). Then fine cut 2 with a white pad, usually 4 inch as well. The wet sanding can be disturbing the first time you do it and you have color washing off your boat, but care and patience will remove the scratch unless it is real deep and thru the gel-coat. Also, after wet sanding, the area worked will be dull and ugly after it dries. Don't freak out, the 105 followed by fine cut 2 will buff the finish back to a nice shine and it'll be ready for the normal detailing process.

I use pretty much all meguire products to and use the oxidation remover or fine cut 2 with the white pads, move on to a high gloss polish or glaze with a blue pad, then then a good wax or the 21 synthetic sealant with the black pad. Hand wiping (removal) between products with micro foiber towels and after the last removal I hit it with a 7 inch lambs wool pad at around 5K RPM and lightly buff it to a wicked shine. I mix is up and use what seems to be needed depending on how bad the finish is.

I am right in the middle of detailing the boat at the moment. I have wet sanded out some scratchs and buffed the wet sand areas with 105 and then 2 and have one entire side detailed to the last high shine buff. As soon as I can stand up again I'll start working on the other side. The transom will be tomorrow probably.

I don't usually mask off anything except the Hull ID letters as the polishes will tear up the lettering. My boat is currently nekkid so I don't need to worry about graphics. I don't really have any problems with splatter, I use low speed to apply the product to the area being worked and speed it up after to work the product. Turn the buffer on and off while the pad is in contact with the boat. If you are getting splatter you're doing it wrong, either too much product or too much speed until the product has been spread out (applied) to the area to be worked.

Check out AutoGeek.com, they have a lot of information about the various products and usually have pretty competative prices although I do tend to shop around for specific iteams and Amazon is my friend LOL

mnpracing
09-09-2011, 05:56 PM
The two machines you posted are in fact different. The polisher just spins the head, while the sander oscillates the head while spinning. It is my understanding that a polisher is what is needed. Also, it needs to have a reliable speed control. If the speed is controlled by the trigger, it is too easy to get the speed too high and burn the gelcoat. Some of the polishers have a thumb wheel to set the speed separate from the trigger. There is a maximum speed at which polishing should be done, and it varies according to the surface and what product is being used.

.

I can only speak to the 7424 Porter cable, because that is what I have. It is a random orbital polisher, so the head spins AND oscillates. It has a speed control dial on the end. A great site to look for how-to's is www.detailedimage.com. You can search the 'ask a pro' section for specific topics. I've found it to be a very useful site. http://www.detailedimage.com/Porter-Cable-M17/7424XP-Random-Orbital-Buffer-P331/

viking
09-09-2011, 06:25 PM
I use the Porter Cable Dual Action Buffer/Polisher. Porter Cable 7424 XP

For a scratch of any real depth, I guess meaning you can feel it when you run your finger nail over it, I use the 2000 wet sanding, by hand, using a small rubber block to ensure no finger grooves. After the 2000 wet sanding I use Meguires 105 and a 4 inch meguire cutting pad (sort of maroon colored). Then fine cut 2 with a white pad, usually 4 inch as well. The wet sanding can be disturbing the first time you do it and you have color washing off your boat, but care and patience will remove the scratch unless it is real deep and thru the gel-coat. Also, after wet sanding, the area worked will be dull and ugly after it dries. Don't freak out, the 105 followed by fine cut 2 will buff the finish back to a nice shine and it'll be ready for the normal detailing process.

I use pretty much all meguire products to and use the oxidation remover or fine cut 2 with the white pads, move on to a high gloss polish or glaze with a blue pad, then then a good wax or the 21 synthetic sealant with the black pad. Hand wiping (removal) between products with micro foiber towels and after the last removal I hit it with a 7 inch lambs wool pad at around 5K RPM and lightly buff it to a wicked shine. I mix is up and use what seems to be needed depending on how bad the finish is.

I am right in the middle of detailing the boat at the moment. I have wet sanded out some scratchs and buffed the wet sand areas with 105 and then 2 and have one entire side detailed to the last high shine buff. As soon as I can stand up again I'll start working on the other side. The transom will be tomorrow probably.

I don't usually mask off anything except the Hull ID letters as the polishes will tear up the lettering. My boat is currently nekkid so I don't need to worry about graphics. I don't really have any problems with splatter, I use low speed to apply the product to the area being worked and speed it up after to work the product. Turn the buffer on and off while the pad is in contact with the boat. If you are getting splatter you're doing it wrong, either too much product or too much speed until the product has been spread out (applied) to the area to be worked.

Check out AutoGeek.com, they have a lot of information about the various products and usually have pretty competative prices although I do tend to shop around for specific iteams and Amazon is my friend LOL

KSmith did a pretty good job of explaining it all right here!!
I'm fairly new at this as well but after reading and researching, this is pretty much my protocol.
I ended up making my purchase on autogeek.com for the porter cable and pads.
It's my winter therapy :)

KSmith
09-09-2011, 07:48 PM
Yeah, my detailing gear is fairly new too. I talked to a couple detailing places to get the scratches sanded out and the exterior polished and waxed and they wanted around 300 as an average. So being the cheap bugger that I am figured for 300 I could get a pretty good detailing setup myself with the DA polisher/buffer, a mix of pads (4 and 6.5 inch), pad cleaner & conditioner and velco backing plates (3.5 & 5 inch) , some polishing/buffing products (a vast mix of Meguire liquids, cutting, cleaning/oxidation remover, polish, glaze, wax, etc). Some of the waxes and polishes, wet sand paper & sanding blocks, stuff like that I already had. I think I went over the 300 a bit but I can use these tools and supplies many times rather than one shot at the professional detailers... I can also use them on my truck, Jeep, and car, and maybe even my riding lawn mower ;-)