# Newbie to wet sanding- tips and advice please!



## detalierg (Nov 4, 2013)

Hi All,

I would appreciate any advice or tips when wet sanding as I've never done it before and really quite nervous and worried I may wreck my paint.

I've brought myself some 2000, 2500 & 3000 grit paper sheets and have some touch up paint for the stone chips on my bonnet. 

I thought i would fill the chips using a toothpick with paint on the end and then wet sand the paint level and then polish the marks from wet sanding with my DA polisher.

Also what is best to use as a lubricant when wet sanding. I've seen videos where water has been used or with clay lube. 

If anyone can advise me on the correct procedure to follow or any advice or tips for a newbie, I would be eternally grateful :thumb:

Thanks in advance


----------



## Ge03 (Jul 19, 2011)

Wet Sanding is one way to do it. 
Stage one is giving the paint time to really harden. Then assuming the abrasive is intended for paint rectification (cheap stuff tends to loose some of the abrasive particles that become grit between the abrasive and the paint), put the abrasive to soak into a bucket of water for at least a couple of hours ideally. Whether or not to use a sanding pad tends to divide opinions but I reckon a pad is safer for those without a lot of experience, lube can be just water but a little shampoo in the lube water can help, but not enough to cause suds. Sanding technique is generally to use nice straight strokes in one direction, gently overlapping as you work across the panel and keeping the work area sprayed with fresh lube to prevent any possible grit contamination, you don't need loads of pressure, just firm enough to keep the cutting particles working the paint. As you step up through the grit sizes change the direction of work, so 2000g go across, 2500 go up and down, this makes it easier to see when all the 2000g marks have gone, then 3000g back to working across. Don't be tempted to skip a grit grade. 

Or, just get a De Nibbing block and some abrasive 'daisies' from someone like Festool where you only need to sand the touched up paint about the size of a 50p. Same basic rules apply but the area you work is much, much less :thumb:


----------



## detalierg (Nov 4, 2013)

Thanks GE03 for the advice. :thumb: 

I brought the megs wet sanding grit papers as I somebody warned me that cheaper makes tend not be as good. I also have the megs sanding block as well to use. 

Just waiting for a break in the weather to give the car a good clean so i can get the chips painted at least.


----------



## suspal (Dec 29, 2011)

Do you have a paint thickness gauge?


----------



## detalierg (Nov 4, 2013)

Yes i do


----------



## Big Buffer (Jan 1, 2011)

Keep an eye on readings between each paper


----------



## Guest (Feb 25, 2014)

I've been going through the same steps as the OP with the same materials on several stone chips but one thing still eludes me.

I've been using Chipex touch up paint - with a recommended drying time of between 10 mins. and 24 hours. I've tried these and several other time periods in between but after rubbing down there's always a smaller "crater" left behind. The paint just does not seem to stick 100%. I'm still fighting one chip after 4 days of effort!

Should I be leaving it for more than 24 hours before rubbing down? Any other tips much appreciated.


----------



## detalierg (Nov 4, 2013)

I was under the impression that you apply a coat of paint to the chips and then wait for them to dry for the recommended time and then added another coat on top and keep building up until the chip is fill and has leveled out. Then I would start wet sanding.

I may be wrong and I'm hoping someone can advise if this is right as I don't want to be in the same boat so to speak.


----------



## Guest (Feb 25, 2014)

That was my impression too. I've dripped one "blob", which has more than covered the whole chip and is above the bonnet surface. Yet, when I rub it down a small amount of "below top surface" paint always comes away. It's as though the paint is just not bonding in the depths of the chip.

...and I've used IPA so I don't think there are any wax residue issues. 

The good thing is the sandpaper scratches polish out nicely, so that's one less thing to be worried about


----------



## justinio (Jun 24, 2013)

Sounds like you are going too thick with the paint. Try a few lighter coats so the 'blob' builds up in the chip, otherwise if you do just one big blob the paint will just end up being pulled out of the chip. Give the paint a good amount of time in between coats to harden.


----------



## s_hosgood (Mar 18, 2007)

Are you cleaning out the stone chip with some sort of IPA or wipe down product first? This happened to me one and it was because there was some residual product in the bottom of the chip.

Happy painting


----------

