wet sanding swirl marks

leoo24

Petty Officer 2nd Class
Joined
Aug 10, 2008
Messages
141
Hi guys :)


okay so i'm trying to remove some oxidation from my gel coat, have read loads...


I tried wet sanding a small patch with 800 grit, worked great at removing oxidation but it left faint swirl marks. Is this normal?

I've got rubbing compound, does this remove the swirl marks if that's normal?
I've got to use an angle grinder with a buffer attachment right? by hand is just too much work i guess.

I'm in spain and our selection of products is extremely limited. 800 grit was the finest i could get.

cheers

:)
 

cc190cc

Petty Officer 2nd Class
Joined
Jan 17, 2010
Messages
198
Re: wet sanding swirl marks

A high speed buffer will make getting the swirls out alot easier. You could prob do it by hand though, you gotta get some 1000 and 1500 like the other guy said and go over it with that.
 

Dzrtcj7

Petty Officer 3rd Class
Joined
Feb 15, 2010
Messages
88
Re: wet sanding swirl marks

You'll definitely want to go from the 800 to 1000 grit, then maybe even higher in high visibility areas before you buff it out. Sand in straight lines with a foam sanding block. It takes a lot of time and patience to get the sanding marks out. You'll want to hit it with a power buffer and some aggressive, heavy cut compound. That compound will still leave light swirl marks, so if they bug you, step up to a lighter cut swirl mark remover, then top it with wax.

I would NOT use an angle grinder with a buffer attachement, unless it spins at less than 2800 rpms or so. It probably turns way to high of RPMs to effectively buff with out burning.

I'm not sure if you ran across my thread, but there are pictures of my progress there: http://forums.iboats.com/showthread.php?t=374293&highlight=vindicator

Hopefully you can find some higher grit paper. If you have any more questions, please feel free to ask me.
 

leoo24

Petty Officer 2nd Class
Joined
Aug 10, 2008
Messages
141
Re: wet sanding swirl marks

Thanks guys :)


i'll try to get above 1000 grit, i'm going to a nearby city next week, hopefully an outlet there will have some

it's really really hard to get stuff here.


@Dzrtcj7 your boat came out really nice!

i'll check my angle grinder, it's only a llittle cheapo which i have a feeling is pretty low rpm.

i've also got a cheapo buffer
http://ecx.images-amazon.com/images/I/21XGAHS2KTL._SL500_AA250_.jpg

do these do anything? or are they not powerfull enough

cheers

Leo
 

Spinnaker

Petty Officer 1st Class
Joined
Jul 5, 2009
Messages
210
Re: wet sanding swirl marks

As said by Dzrtcj7 don't use the grinder as you cannot adjust the speed. You need to keep things cool and the grinder will heat the surface too much. The picture you show is an orbital polisher. Good for applying wax and that is it. Unless you have a variable speed polisher it looks like you're doing it by hand.
also you can get away with polishing out 800 grit wet sand but only with a variable speed polisher. It will be highly recommended to wet sand with 1500- 2000 if you are faced with cut polishing by hand.
 

leoo24

Petty Officer 2nd Class
Joined
Aug 10, 2008
Messages
141
Re: wet sanding swirl marks

Thanks.

may have found a workaround for the polisher, my local hardware store had a polishing attachment for a drill, so checked my bosch power drill rpm, 800 rpm!! so i would be good to use this? also checked my angle grinder out of curiosity just for comparison and it was 11000 rpm.
 
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