View Full Version : Color Sanding Delfleet SS Polyurethane?


09-12-2016, 02:37 PM
Iíve applied and worked with older single stage enamels without serious issues, but that was ten years ago. Since this is my first time using PPG Delfleet, single stage polyurethane enamel, I hope you can set me on the right path so I donít screw it up.

The paint is creamy white, solid color, non-metalic with hardener and slow activator.

I painted the car outdoors yesterday when the air was calm. The first coat was beautiful with no runs, very little orange peel, and only a couple of gnats committing suicide. Temperature was about 75F when I began, and by the time I finished the recommended second coat, the temperature had risen to about 85F. The result was some orange peel and a few spots of dry overspray in areas exposed to direct sunlight. Still not bad, but needing some repair.

My question is what steps should I take to repair the defects?...and how long should the paint cure before attempting those repairs? Wet sand? Dry sand? The data sheet says to wait 72 hours before repainting, but I doubt the paint is hard enough to repair that soon.

Hereís what a local painter suggested: Wait a couple of weeks, wet sand first with 1200, and then with 1500, followed by a good buffing compound. He didnít suggest which compound to use, or what type of pad, and what buffing speed. I have an old Porter-Cable 6Ē variable speed, DA buffer that should provide the elbow grease.

The car is not a show car, but is a weekend driver that will always be garaged.

Thanks for any and all suggestions.

09-12-2016, 03:01 PM
Hi Gary
I haven't used that paint so I don't know how long it takes to get hard but I use several different products and none of them take more than a couple days before I can sand and polish. I would sand using 1500 wet sanding paper then polish using a wool or orange foam pad and Wizard's Mystic Cut compound. Start by using a slower rotation and more pressure then go back over it with less pressure and higher speed rotation.

LINK (http://autobodystore.net/Merchant2/merchant.mvc?Screen=PROD&Store_Code=ABS&Product_Code=3MJOBPACKs&Category_Code=M3)

LINK (http://autobodystore.net/Merchant2/merchant.mvc?Screen=PROD&Store_Code=ABS&Product_Code=WIZ11048&Category_Code=M3)

LINK (http://autobodystore.net/Merchant2/merchant.mvc?Screen=PROD&Store_Code=ABS&Product_Code=SFPADS&Category_Code=T2)

09-13-2016, 07:02 AM
Thank you for the good advice and suggestions!

09-13-2016, 09:40 AM
be careful with the sanding. it sounds like you only have two coats of paint so the chance of burn through is high. most folks that plan top cut and buff put on a little more.

09-13-2016, 09:55 AM
I don't think others noticed what machine you said you wanted to use. That porter cable isn't going to come close to taking out 1500 sandpaper scratch.

You have two options - the one I suggest is - get a rotary and a 6 inch backing plate. I use the Hitachi SP18VA and think you should look closely at it because it will run all the way down to 600 rpms. At that speed with a 6 1/2 inch pad you'll have a pretty hard time getting in trouble as you learn how to run it and speed the machine up.

Cut with the wool pad, then follow up with an orange foam pad like Len said.

The other alternative would be to cut with 1200 on the nibs, but with a small block, then 1500 on a regular medium hardness block, then go to 2000 by hand, no block, then 2500, again no block, 3000 no block, 4000 on the porter cable or your DA sander with a soft interface pad, 5000 again with the sander or porter cable with soft interface pad. Then because you should be working with a scratch the porter cable has some hope of cutting, use the Wizard polish on the orange foam pad and still expect to take some time.

Good luck,