So, I'm finishing off my tub mould at the moment, and I'm looking for advice on the best way to polish it up...

I've flatted it with P800 on a DA orbital sander, and that went very well, and then I've taken the flat down to P1200 on the same sander which equally went well and was quite satisfying.

I can now either buy (which I don't mind) some P1500 and P2000 disks (from East Coast Fibreglass) to finish up the process. I've also got a selection of the next grades as wet-and-dry if I want to complete the scratch-removing process by hand.

None of this is the crux of my problem. I *also* have the machine-mart 3 stage liquid polishing system like this, with three liquid polishes - one for removing scratches at P1500, one for P2000, and then the final gloss and swirl removal.

So, does anyone know whether it's best to go up to 1500, then use the polish, then go to 2000 wet-and-dry and polish again before swirl-removal, or is the right approach to use the polish that is targeted at the grit you would stop at. So, if I stop at P2000 by hand with wet-and-dry, then that's the only polish to bother with?

Thanks
Mark

I've always (rightly or wrongly) treated polish like a 'liquid sandpaper', IE it does the job of the equivalent paper. I wouldn't go back a grade in the sequence because all you'll be doing is cutting deeper into the finish unnecessarily.

The decision of when I would move from sandpaper to polish would be based on cost and ease. I normally go from sandpaper to polish at around the 2000 point, mainly because that's the kit that I have. If you have P1500 polish but not paper, then it would make sense to switch over to the polish at that point, rather than buying additional abrasive at the same grade.

I spent a few years in the fibre glassing industry and only needed p1200 with a bar of soap and some farcela g7 to get a very good finish

First of all do the final flatting by hand with 1200 wet and dry (i go 2000 but i am pedantic) i then machine polish with g3 and plenty of water if you get stuck i am only in teesside and can lend you my polisher for a few days as long as you can pick up and drop back off cause i do use it all the time i have even got g3 here too

[Edited on 28/11/16 by Vmax1974]

Again, G7 is what I use with a polyester gelcoat, with (perhaps) a finish off with G10 if I've used a vinylester tooling gelcoat.

Rotary mops (blue and red) do the job very quickly, but must be lubricated/cooled with copious amount of water. Makes a lovely mess!

quote:

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Originally posted by motorcycle_mayhem
Again, G7 is what I use with a polyester gelcoat, with (perhaps) a finish off with G10 if I've used a vinylester tooling gelcoat.

Rotary mops (blue and red) do the job very quickly, but must be lubricated/cooled with copious amount of water. Makes a lovely mess!

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Description


Description

One half of the tub flatted and polished. The light isn't great to show it off, but it's in good shape. This should certainly help the release.