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Does it need wet sanding?
Posted: Fri Apr 15, 2022 7:29 am
by KrisA
Posted here a few times and we just recently had the interior redone by Coz. I’m trying to get the exterior to match the interior now.
Used Presta gelcoat compound with a white wool pad, but I don’t think it’s enough to get the white gelcoat back to a nice shine. Thoughts?
Re: Does it need wet sanding?
Posted: Fri Apr 15, 2022 7:46 am
by VTENGR
Probably going to need a stronger compound. There's several YouTube videos of detailers using 3M CUT products in lieu of wet sanding. It seems 3M is the product of choice.
Re: Does it need wet sanding?
Posted: Fri Apr 15, 2022 9:24 am
by tomace13
Are you compounding by hand or with a buffer? You’ll kill your shoulder trying to get it to a mirror finish by hand.
Re: Does it need wet sanding?
Posted: Fri Apr 15, 2022 9:54 am
by dustinm
You shouldn't need to wet sand that, just more time with your current compound or find a more aggressive one, with 3M being the best. It is better to use your approach as you can ruin the finish (I have on a pickup door one time trying to remove dog claw marks).
The interior looks factory.. they do fabulous work!!! How do they do the monogram? As it looks factory also
Re: Does it need wet sanding?
Posted: Fri Apr 15, 2022 12:14 pm
by jhnmdahl
I agree - I don't see sanding here, just a more aggressive compound and a good orbital buffer (or a dual action buffer if you're fancy).
John
Re: Does it need wet sanding?
Posted: Fri Apr 15, 2022 5:30 pm
by KrisA
Appreciate the info everyone. I’ll order some of the 3m products and see if it will make better progress. I have a dewalt orbital that I’m using.
Re: Does it need wet sanding?
Posted: Fri Apr 15, 2022 7:05 pm
by Titaniumboy
Gelcoat is far harder than automotive clear coat. And Cobalt’s gelcoat is supposedly harder than many other gelcoats.
Try 3M Heavy Cut and work it until you can’t see any compound and then keep working it some more. You should be able to see your reflection when you’re done. Take it to the next level with 3M Perfect It EX AC to get rid of any swirls and get an even deeper reflection. Use a rotary buffer with quality wool pads.
Seal in the newly compounded and polished surface with some Meguiar’s Flagship Marine Wax.
This is what CobaltChats baktasht was able to do with just compounding and no wet sanding.
viewtopic.php?p=90387#p90387
And what YouTube channel “local boydidgood” was able to do with a heavily oxidized black Cobalt. Your white hull will almost certainly not need the 3M Super Duty.
Re: Does it need wet sanding?
Posted: Thu Apr 21, 2022 11:56 am
by Lockey14s
The way to tell if you need to wet sand is by rubbing your hand over the gel coat and feeling the texture and listen to the sound. if its still smooth and doesnt sound like like you are running your hand over sand paper, then you can go to heavy cut compound. but if it feels grainy at all and you can "hear" it and you are getting chalk on your hands, then you will need to wet sand.
In my opinion you should start with wet sanding if you want to make it match that beautiful interior. One pass of 500 grit and then another with 1000 should get you back to good gel coat. then use a heavy cut diminishing compound (Starke Level-R, Smoove Pro cut, etc, etc) on a wool pad with a rotary buffer. DO NOT use an orbital for this step, it will get you nowhere. Then use a polish (Menzerna 400, Starke elevate, etc) on a foam pad with the orbital to get all the halos and fine scratches out. next wash the boat with dawn to get all the oils off, then apply sealant to protect it for the season.
a lot of products will claim you dont need to wet sand and that it will take off all the oxidation, blah blah blah. which is true.... it will remove the oxidation, but what it cant do is cut down far enough to a smooth fresh gel coat and over time the oxidation will just come back. in the long run its just better to wet sand now and save headache down the road.
Mirka Abralon sanding pads make it easy and relatively safe to use on an orbital
Re: Does it need wet sanding?
Posted: Thu Apr 21, 2022 10:42 pm
by Titaniumboy
More nasty oxidized Cobalt gelcoat