Good advice, after reading this, I was doing a couple things wrong. I think I was using too slow a speed and working a larger area on my final buff. Although I was trying to remember the DVD that I purchased with my 7424 about final buffing/polishing and I thought it mentioned to slow the buffer speed and it's ok to work larger areas. I'll have to re-watch that DVD and take better notes.
AFTER you have machine polished paint using a dedicated machine polishing process the surface of the paint will be clean and smooth and at that point you can use a slow speed and tackle huge areas because all you're trying to do is spread a finishing wax out over a perfected surface.
You didn't say if the gel-coat was oxidized or not so I did something I don't like to do and that was to take into account that gel-coat, (polyester resin), oxidizes easily, especially on "things" normally stored outside and I assumed that at a minimum there was at least light oxidation on the surface.
If the above is accurate (and it might not be), but if it is, then using a cleaner/wax like M20 Polymer Sealant on an oxidized surface isn't the same as what I explained and demonstrated in the DVD which was applying a non-cleaning wax to a surface previously polished and prepared for the wax.
If there is light oxidation at a minimum, then you want and need the higher speeds for the POWER to make use of the small amount of cleaners in the M20 product to work them against the surface and remove the dead, oxidized gel-coat AND smooth the surface over to restore gloss, clarity and shine.
You'll get better results using a higher speed and working a smaller section.
The above is all just a guess because you haven't shared the condition of the gel-coat surface.
If the gel-coat surface is like brand new, that is clean, clear and shiny, then you still want to use at a minimum the 4.0 to 5.0 speed setting on a PC because those are the speeds that will keep the pad rotating and oscillating under even light pressure but if the surface is in excellent condition then you could tackler larger areas.
Still don't buff to a dry buff... you want to leave a wet film on the surface to dry and then wipe it off after it dries.
One characteristic about M20 is that it dries fast and is INCREDIBLY easy to wipe off when used correctly, so if it's not wiping off easy then something is wrong somewhere.
It also leaves a very slick surface, next time you wipe some of it off, feel the surface and tell us what you think.
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