Board logo

What polish for GRP?
Sloan85 - 1/9/13 at 04:09 PM

I covered my car in polythene when I trailered it the other week as heavy rain was forecast. This was a mistake as the polythene has blown about in the wind and dulled areas on every panel. What is the best polish for bring the gel coat back to a gloss finish? I have some Autoglym Super Resin Polish fomr when I was into detailing my Civic Type R but not sure whether these products designed for paint can be used on gel coat.

What about waxing the GRP. Any product recommendations?

Cheers


jacko - 1/9/13 at 04:31 PM

Autoglym is what i use


Sloan85 - 1/9/13 at 04:44 PM

cheers, ill give that a go.


jacko - 1/9/13 at 04:57 PM

Description
Description


read my roll bar sticker


Volvorsport - 1/9/13 at 05:03 PM

Farecla g3 then mould release wax


twybrow - 1/9/13 at 05:12 PM

quote:
Originally posted by Volvorsport
Farecla g3 then mould release wax


Another vote for Forecla products - they are the industry standard for gelcoat finishing.


doobrychat - 1/9/13 at 05:32 PM

G3 is Gods cream in my eyes.. blooming excellent stuff but beware of immitations on Farecla products...


jacko - 1/9/13 at 06:01 PM

quote:
Originally posted by doobrychat
G3 is Gods cream in my eyes..
I bet that stings


Xtreme Kermit - 1/9/13 at 06:43 PM

Autoglym Super Resin Polish on my shelf.


Sloan85 - 1/9/13 at 07:12 PM

Had a go with the Autoglym SRP but it isn't shifting the marks. Is there a more abrasive polish or do I need to have a go with a rotary polisher?

Cheers


ashg - 1/9/13 at 08:05 PM

farcella g3 with an electric mop and plenty of water its the only way.


mark chandler - 1/9/13 at 08:05 PM

My vote is for meguiars compounding polish, be careful with a rotary you may burn the surface unless you know what you are doing.


plentywahalla - 1/9/13 at 08:53 PM

Polyester gel coat is very different from paint in that it suffers from oxidisation and chalking caused by Ultra Violet radiation. Ordinary waxes such as beeswax or carnuba will give a good shine but their UV protection will last only about 50 hours when exposed to sunlight.

You need a polish with long term UV barrier protection which usually means ones containing Silicones. The problem with Silicones is that they are highly mobile and can migrate into the gel coat itself. This leads to adhesion problems when the gel coat is subsequently repaired or refinished, it can also lead to embrittlement over the longer term. We always recommend that Gelcoats are polished with Polishes containing PTFE which has long term UV protection without the problems associated with Silicones.

Note that polish manufacturers sometimes use trademarks for PTFE such as Teflon and PTEF in their descriptions.


Sloan85 - 1/9/13 at 09:23 PM

quote:
Originally posted by plentywahalla
Polyester gel coat is very different from paint in that it suffers from oxidisation and chalking caused by Ultra Violet radiation. Ordinary waxes such as beeswax or carnuba will give a good shine but their UV protection will last only about 50 hours when exposed to sunlight.

You need a polish with long term UV barrier protection which usually means ones containing Silicones. The problem with Silicones is that they are highly mobile and can migrate into the gel coat itself. This leads to adhesion problems when the gel coat is subsequently repaired or refinished, it can also lead to embrittlement over the longer term. We always recommend that Gelcoats are polished with Polishes containing PTFE which has long term UV protection without the problems associated with Silicones.

Note that polish manufacturers sometimes use trademarks for PTFE such as Teflon and PTEF in their descriptions.


Excellent information! Thanks for that.

Can you suggest any products? Cheaper the better at the minute!

Cheers


plentywahalla - 1/9/13 at 09:38 PM

Look here

Linky

Richard

[Edited on 1/9/13 by plentywahalla]


theduck - 2/9/13 at 06:24 AM

Forgive me if i am wrong, but are polishes not meant for correcting paint and sealants and waxes for protection?


Slimy38 - 2/9/13 at 08:10 AM

quote:
Originally posted by theduck
Forgive me if i am wrong, but are polishes not meant for correcting paint and sealants and waxes for protection?


I believe that is correct, polishes by definition are effectively abrasives (albeit incredibly fine abrasives), whereas waxes just lie on top. If the OP has dull panels then I believe a polish is the best product, at least initially.

It has always made me cringe when people say that they polish their car every weekend, it should not be necessary. A wax every weekend might be ok (although still overkill), but polish is removing clearcoat/paint.


plentywahalla - 2/9/13 at 08:24 AM

I think you are identifying the difference between compounds and polishes.

Reality is most of the compounds sold for use on paint attempt to do both and contain waxes and silicones for protection as well as the abrasives for cutting back the surface. They are in effect a one step process.

I was trying to answer the OP's question and highlight the difference between paint and gelcoat, and that a product designed for one was not ideal for the other.

I usually find the best results are obtained on gelcoat by using a separate abrasive compound and then a pure polish.


Mozzie - 14/9/13 at 03:07 PM

Are you doing it by hand or do you have access to a Rotary or DA?

By hand then the SRP will do, but you will have to use elbow grease to get the results.

I wouldn't use G3 without going to G10 after, the G3 WILL leave micro marring due to its "cut".

I use menzerna on GRP (2 stage) followed with a wax. (Thats using a DA by the way).


I always read the blurb about PTFE in products and wonder how they get it to bond to the paint/grp without the heat that is needed to get it to bond.