posted 10-10-2014 11:11 PM ET (US)            

If the oxidation is extremely heavy you may need to wet sand.

3M has a few excellent youTube tutorials that really helped me.

I used a PORTER CABLE random orbit polisher with Velcro foam pads. I bought the polisher and pads from Griot's garage. Griot's garage has excellent polish removal cloths. I use all of their stuff for detailing my cars.

posted 10-11-2014 11:12 AM ET (US)            

Thank you. That helps provide the steps I need to take to get this done.

posted 10-11-2014 11:17 AM ET (US)            

Many report getting good results using COLLINITE FLEET WAX, a heavy and old-fashioned paste wax.

My advice--which is certainly very non-expert advice--is to start with hand application of any polish or compound, as a test. Work by hand in a small area, and see if the product gives good results. For example, if you think the gel coat surface is already in sufficiently good shape that its shine can be restored with a very mild abrasive like 3M FINESSE-IT, try that product in a small area and see what result you obtain. If you get a beautiful high-gloss result with such a very fine abrasive, then you can plan on using that for the entire boat. If you don't see much improvement, you may need to use something more abrasive as the first pass.

As I recall, it has even been suggested that four steps might be necessary:

--oxidation remover
--polish
--super-fine polish, like 3M FINESSE-IT
--wax

Exactly what you will need to restore the gel coat on your boat will depend on the state of the finish it has now.

posted 10-11-2014 04:16 PM ET (US)            

Thank you for the information. I just wasn't sure whether there were any BW specific concerns, and you've answered that for me.

posted 10-11-2014 07:58 PM ET (US)            

Imperial Glaze is an oil based filler. On cars, it is mostly used to disguise swirl marks (rather than actually polishing them out).

Finesse-it is an actual polish...i.e. an abrasive designed to remove marks and level out scratches.

The correct order would be finesse-it, imperial glaze, and then wax. Basically, "polish out scratches, disguise the ones you don't remove, and then protect the surface". If you're polishing after you glaze, you're removing the oil which is what the glaze is really all about. Most automotive polishes also contain oil/fillers, so you're probably not noticing a huge difference, but glazing then polishing is just adding an extra step. Do the reverse or stick with just polish and wax to save a step.

For auto, I personally use polishes that don't contain oil so I can see the actual condition of the paint as I work. I polish out the swirls and then protect, rather than using glaze to cover them. If you're careful with how you treat the car in terms of washing, there's not really a good reason to use glaze, but if the vehicle is treated more roughly, then it can definitely save a lot of work (and clearcoat) not having to polish it over and over again.

For marine, just like a car, it would depend on how far you want to take it in terms of surface quality, though I doubt you're going to see defects in gelcoat as easily as you do in auto clearcoat.

The porter cable 7424 is a great tool for both auto and boat. You can't burn the paint on a car with a random orbital like you can with a rotary polisher. The tradeoff is that it takes a lot longer to take any scratches out. For gelcoat, if I were using a porter cable, I would use a heavier abrasive and a wool pad. For auto paint you want to stick with a foam pad, but a heavier polish still isn't a bad idea to speed up the process.

posted 10-11-2014 08:05 PM ET (US)            

I haven't done the research yet to see if polymer sealants are popular for gelcoat yet. If they are, they're worth a look. They last forever, they don't stain trim, and they're not hard to work with. I actually discovered last weekend that Klasse All-in-One and Sealant Glaze work great for protecting the black plastic parts of my FJ Cruiser as well as the paint.

posted 10-13-2014 09:35 AM ET (US)            

With polish, it's mostly about time and effort. Not always, but usually, you can achieve the same results with a light polish as you can with a heavy one...it will just take more time and effort. For a surface that needs a lot of work the "by the book" method is to use a heavier polish, then step down to a lighter one to achieve the best shine possible.

I really don't work with 3m products very much because they contain so many fillers, so it's tricky to say what kind of results you'll get with it (also not knowing your boat and experience level). If the yards suggested Super Duty, then that's probably a good recommendation. Depending on how picky you are, you may want to follow up with a lighter polish, but it doesn't sound like you're overly picky.

Honestly, as picky as I am about cars, I wouldn't follow up with a lighter polish either unless it was really obvious that I needed to. Detailing is cumulative...hit it with the heavy polish this year and maybe go lighter next year when it's in better shape. I'm a big fan of this type of approach.

If the yards were stressing hand application, that also plays in to their polish recommendation - i.e. they're recommending a heavier polish because hand application is less aggressive and takes more time and effort. If you do it by hand I would just get some basic hand pads from autozone or west marine and go at it. Keep applying until you've removed the oxidation you're looking to get out.

If you go with the machine, I would use a foam pad and relatively low speeds. A rotary with a foam pad set on its minimum speed is still going to be more aggressive than hand polishing. Just make sure you keep the machine moving steadily all the time, don't sit on bumps or edges, and start out on flat easy panels until you get good at controlling the machine.

I would do the machine myself. Hand pads are cheap, though, so buy a couple and see if hand polishing it seems reasonable. If it's too much effort step up to the machine and don't be too aggressive.

Just another general side note - I learned the hard way (by burning my paint) when I first got my rotary that the "default" speed should be the minimum speed of the buffer. Always start out at that speed, use it when you're anywhere near an edge or a bump, etc. When in doubt, use the minimum speed. If you regard higher speeds as a "tool" to get the work done faster on panels where its safe to do so, that will usually keep you out of trouble. Keep the machine moving all the time. Minimum speed usually won't cause too much trouble if you stop moving, but at high speed the buffer will burn through paint in (literally) a second if you stop. Using high speed you need to make sure you're in a comfortable and stable position so you can control the buffer and keep it moving. If you're in an awkward position bending or reaching, don't use high speed.

Gelcoat is a little tougher than clearcoat, but treating it like a car will keep you out of trouble until you get a better feel for it.