Wetsanding gelcoat

[Theraven]

Tips for Wetsanding gelcoat/boats by hand, I have a standard 3m rubber sanding block, and a foam sanding pad. What pressure, direction/motion, when to stop/what to look for, where not to sand and when to change the paper? I know to keep spraying water with a little soap, and to rinse or clean between grits to avoid tracers left behind. Experimenting on an extra panel I used the rubber block with just a plain sheet of s paper, after a pass or two it would stop gliding and stay in place like a suction cup. I cut a thin sponge to fit the bottom of the block, wrapped the paper tight around it and it now glides smoothly a lot longer! Not problems with the sanding pad. Also if I stated at 1000, Would you jump to 1500 or 2000, any general rule about that. In general, could be many factors but is it usually better to start off with an finer grit and move up or down depending on the surface outcome or just use a fine grit even if it takes longer. Thanks you for anyone who responses, in advance. I know there's a lot of questions but and help would be great!!!

[Shtexas]

I used 3m imperial wet sand paper. started at 800, then 1000, then 1500, then compounded with the rotary. That was for my super oxidized 1992 Sea Ray. The horrible look of the gelcoat helped me get a deal. I switched the paper out pretty frequently and rinsed the gel coat in between grit changes. I used straight line technique and cleaned the paper off frequently.
I figured out after wetsanding that boat that it usually isn't necessary to wetsand unless your gel coat is insanely oxidized. Rotary with a wool pad and a heavy cut compound works wonders.

[Flash Gordon]

Tips for Wetsanding gelcoat/boats by hand, I have a standard 3m rubber sanding block, and a foam sanding pad. What pressure, direction/motion, when to stop/what to look for, where not to sand and when to change the paper? I know to keep spraying water with a little soap, and to rinse or clean between grits to avoid tracers left behind. Experimenting on an extra panel I used the rubber block with just a plain sheet of s paper, after a pass or two it would stop gliding and stay in place like a suction cup. I cut a thin sponge to fit the bottom of the block, wrapped the paper tight around it and it now glides smoothly a lot longer! Not problems with the sanding pad. Also if I stated at 1000, Would you jump to 1500 or 2000, any general rule about that. In general, could be many factors but is it usually better to start off with an finer grit and move up or down depending on the surface outcome or just use a fine grit even if it takes longer. Thanks you for anyone who responses, in advance. I know there's a lot of questions but and help would be great!!!

As far as what direction with the sanding, back and forth would be the way I would do it. If you followed with a higher grade paper, then you would go up and down

Unless this individual is giving you a blank check, I think you're taking too many steps. I'm no expert with gelcoat, but if it were me, I would either go with an aggresive compound and rotary/wool OR possibly 1500/2000 grit traditional sandpaper followed with rotary/wool. Your going to leave swirls marks after either of this steps. Most boat owners could care less about swirl marks (it's been my experience) they just want SHINY!!!

[BillE]

What "Flash" said and wet sanding fiber-glass you almost have to use a constant flow of water to eliminate the 'suction' problem.

Bill

[Theraven]

Thanks for the tips, you are so right about the "just want it shiny" My boss is like that,(not me) the more I've learned, the more I've improved my skills/products used. The stuff people get away with, nothing like the hood of a boat with , swirls, marring, scratches, holograms ect... but it's shiny :)

[glen e]

I have been detailing gelcoat for about 15 years and would NEVER wetsand if there is any alternative at all. Just because it takes so much more work to get back from the scratches you put in when sanding. If I can do the job with a rotary, wool pad and super duty compound I will do that all day long. Try and avoid wetsanding if wool and compound will get the job done....Then move to orbital and foam pads for polishing and glossing...

[Theraven]

My boss loves to WS, I always think thought it would do more damage then help.

[Theraven]

Whoops darn IPHONE. My boss loves to WS, and when he Does he just uses his bare hand, a big mistake!! which makes it a bi-ch to remove. If its really really needed I will(and do it correctly), other wise I'll avoid it as much as I can.

[rmagnus]

Why would you sand gel coat by hand? Better be a small boat! If you can use equipment to do the work then use it. Dedicated DA sanders are cheap.

My vote is rotary with wool pad and compound. Follow with a DA.

[hernandez.art13]

Gel coat seems very durable, I have never worked on gel coat. What would happen of a car got painted with Gel Coat? Lol

[Tony@TDC]

I have been detailing gelcoat for about 15 years and would NEVER wetsand if there is any alternative at all. Just because it takes so much more work to get back from the scratches you put in when sanding. If I can do the job with a rotary, wool pad and super duty compound I will do that all day long. Try and avoid wetsanding if wool and compound will get the job done....Then move to orbital and foam pads for polishing and glossing...

Could not say it any better

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