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HotRodMan
06-18-2014, 08:07 AM
I am working on a 1969 corvette that was recently painted with a bright yellow single stage paint. The paint was allowed to dry for two days. The color sanding process was started by leveling the panel with 1200 grit, then sanded with 1500 grit, then sanded with 2000 grit, all wet sanded by hand with solid and flexible blocks. The next step, we polished with a compounding foam pad using Meguiar's Ultimate compound the first time, then a second time with the same compound using a polishing foam pad. When you stand back and look at it the paint finish, it looks perfect, if I turn out all the lights in the shop and look the car over with a hand held light it looks perfect. If I turn on the overhead fluorescent lights , and you get at just the right angle, I can see very minor sand scratches, left from the sanding process (no swirl marks) over the entire surface of the car.

If you think it could be better, what polishing compounds, polish pads, or sandpaper should I use?

What could I have done differently that would have given me a better result? Thanks

junk
06-18-2014, 08:13 AM
A lot of us on here like the Wizards Mystic cut compound and the orange surfinish pad. I'm just getting into using them, but they have yielded the best results I've ever had from buffing.

Some of the pro's should be along anytime....

Len
06-18-2014, 09:37 AM
I am working on a 1969 corvette that was recently painted with a bright yellow single stage paint. The paint was allowed to dry for two days. The color sanding process was started by leveling the panel with 1200 grit, then sanded with 1500 grit, then sanded with 2000 grit, all wet sanded by hand with solid and flexible blocks. The next step, we polished with a compounding foam pad using Meguiar's Ultimate compound the first time, then a second time with the same compound using a polishing foam pad. When you stand back and look at it the paint finish, it looks perfect, if I turn out all the lights in the shop and look the car over with a hand held light it looks perfect. If I turn on the overhead fluorescent lights , and you get at just the right angle, I can see very minor sand scratches, left from the sanding process (no swirl marks) over the entire surface of the car.

If you think it could be better, what polishing compounds, polish pads, or sandpaper should I use?

What could I have done differently that would have given me a better result? Thanks

I tell everyone that if I was still color sanding by hand I'd be retired by now because that is the most physically difficult part of a restoration or paint job. But sanding by had or by machine we follow the same procedure. Unless there are unusual problems we start with 1500 then we either jump to 2500 or 3000. If there are dust nibs in the surface we may use a Nib File first then sand with 1200, 1500 then 3000.

One thing to pay attention to is that these fine sanding scratches are hard differentiate and a 1200 scratch can look very similar to a 1500 or 2000 grit scratch but a 1200 scratch can be much more difficult to remove. So when you start with a more coarse grit you want to be careful to remove it with a finer grit before you polish or you may need to re-sand when you see these coarse scratches after buffing.

I like using 3000 grit Trizact because the paint has a slight gloss to it after sanding and it's a lot easier to polish.


http://www.autobodystore.com/sandingchart.jpg

xtremekustomz
06-18-2014, 04:24 PM
Never used any Wizards but I've had great results out of 3m Rubbing compound on a Meguiars wood pad followed by the same compound on a Meguiars Maroon Pad. A lot of professional detailers are using Meguiars M105. Meguiars M101 is supposed to have a heavier cut but I don't think it finishes out as nice as M105. I recently bought some HD Cut made by 3D Products. It seemed to work really nice as well. They also have a polish called 3D Polish that is amazing. It has no fillers so you will never have an issue sand scratches being masked and later come back as the oils and fillers evaporate. 3D Polish is my now go to final polish although HD Cut and M105 finish out good enough on most colors where polishing isn't needed but I'm a perfectionist so I always do a final polish. I agree with Len on using a DA for color sanding though. They even make a 5000 grit now where basically all you have to do is polish instead of compounding. I've actually removed 1000 grit scratches that were left over from an initial cut with the Meguiars wool pad and 3M Rubbing compound.

Skalabala
07-18-2014, 03:56 PM
There is a big chance that the paint was not cured bud.
I get the same results when paint feels hard but is not completely cured. Two days is way to short in my "shop"