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Wed Apr 30, 2003 8:20 pm

How long should single stage enamel dry before attempting to wet sand and buff?
Thanks

Wed Apr 30, 2003 10:57 pm

Usually around 90 days.
At least thats how long you should wait before waxing.

Thu May 01, 2003 12:55 am

Give it about 48 hours if done in a heated spray booth, if not wait 5-6 days, thats enough.

Thu May 01, 2003 9:51 am

Single stage really should not be buffed.
You lose color retention and run the risk of sanding a light spot.
You can color sand the next day after the paint has flashed off completly around 24hrs is fine. Your paint cures in 90 days or less. Read the can. or the MSDS
Not water washing a car is also a old wives tale after a new paint job for 3 months

Mon May 05, 2003 2:09 pm

If it should not be buffed, then how do you fix the inevitable problems such as runs, etc.

Thanks all for your advice.

Mon May 05, 2003 4:55 pm

Try reading the paint Manf. data sheet, most paints act differently under different conditions. If you wait to long to buff it may be tough to get out the sand scratches. As a paint rep for a major manufacturer, I feel like I can speak to this. If you wait 90 days it may be harder to cut and buff than if you had done it with in 48-72 hrs. Wet sanding actually helps the cure process. The water is the trick. Lets hope the painter put down some material or you may sand thru...then your f&%ked!!
God Luck

Fri May 09, 2003 7:17 pm

I find this thread fascinating for its two completely different viewpoints. You would think there would be general agreement when it comes to so basic a question. I am not a car painter so I do not pretend to know the answer and that is why I asked the question. My 70 Westy has been painted nicely overall but has some orange peel and a few problem areas where it was damaged during reassembly. They need to be fixed so how would those of you who say no to sanding/buffing take care of scratches/orangepeel, etc. Also I understand that for years single stage enamel was the paint used by the car industry. Was sanding/buffing not commonly used at that time?

Thanks for all your discussion.

Sat Mar 24, 2007 7:57 pm

I know that this is a very old thread but does anyone have a good answer to this? Can should and should enamels be color sanded and if so, how long should one wait with and without a hardner?

Thanks, Mark

Sat Mar 24, 2007 8:49 pm

I think the best instruction would be to follow the instructions from the manufacturer for your type of paint, as they will vary.

Sat Mar 24, 2007 9:03 pm

The paint that I'm planing on using is Valspar Suncryl 325. The data sheet does not mention post paint finishing. Since I'm going to paint the car in my garage, I'm expecting to get some nibs in the paint. I sprayed the primer sealer on Friday and there were nibs in that. I'm thinking of wet sanding that out with 600 grit paper.

Is there a rule of thumb for enamel to wait a week or 90 days to sand it out. with like 1500 or 2000 grit paper or just buff it out or what?

Thanks, Mark

Sun Mar 25, 2007 9:20 am

You can safely wet sand after 24 hrs if you live in a hot climate or the car was baked. I personally prefer to wait a week as a balance between a full cure (7 to 21 days depending on your climate and humidity).

Some single stage colors will change in appearance after wetsanding. Meaning you may have to sand every inch of the car to get a uniform appearance. Wetsanding of base /clear colors is more reliable in not affecting the final color. To be safe, plan on applying at least one extra coat of color or clear if you plan to agressively color sand and buff the car to a show car appearance.

You can color sand early or late in the drying process, but when all the solvents are not fully out, and the car is sanded and polished, you may get die-back or dulling of the finished surface at a later date. If that happens you can repolish the surface after curing is complete to bring back the gloss.

The rule of thumb is to use the finest grit that will get the job done. I like to start with 2000 paper if the paint finish is pretty nice to start. And make sure all your sanding blocks, water buckets etc are incredibly clean. One little speck of grinding dust, sand etc, is like having some 40 grit mixed in!! Hope that helps with your project.

Sun Mar 25, 2007 11:00 am

[email protected] wrote: I find this thread fascinating for its two completely different viewpoints. You would think there would be general agreement when it comes to so basic a question. I am not a car painter so I do not pretend to know the answer and that is why I asked the question. My 70 Westy has been painted nicely overall but has some orange peel and a few problem areas where it was damaged during reassembly. They need to be fixed so how would those of you who say no to sanding/buffing take care of scratches/orangepeel, etc. Also I understand that for years single stage enamel was the paint used by the car industry. Was sanding/buffing not commonly used at that time?

Thanks for all your discussion.

I see what you're saying. As a general rule, a good professional painter will not have orange peel or runs that he can not run to the floor and eliminate in the booth. He will occasionally have to sand and maybe spray a little more paint on an area.High speed buffers are dangerous because it is very easy to buff the color off down to the primer. It takes practice and you probably will see primer while you are learning. Good paint applied properly, no problems. If I needed to sand fresh paint, I would ask my supplier for advice. There is lot of different stuff out there today.

Sun Mar 25, 2007 11:08 am

"My 70 Westy has been painted nicely overall but has some orange peel and a few problem areas where it was damaged during reassembly. They need to be fixed so how would those of you who say no to sanding/buffing take care of scratches/orangepeel, etc. "

How deep are the scratches, can you buy a little bottle of touchup paint. Fill them if neccessary. Then sand and buff if needed. Sand and buff for orange peel. Or, take it to a detail shop, and see what they would charge. Those guys get lots of practice with buffers.

Mon Mar 26, 2007 12:32 pm

I posed my paint question to my paint vendor (www.autopaintdirect.com) today and his response was "Yes, you can sand and buff as long as you use the activator. Give it a
couple days before sanding"

Mon Mar 26, 2007 6:03 pm

yeah nibs to be expected in your garage. If you can, rinse off the walls, ceiling, and floor with water the day before you spray paint. Right before you spray paint, you can wet the walls and floor, but definitely not the ceiling. These measures can really help to eliminate dust. Good luck.

Thu Mar 29, 2007 5:01 am

Back to the subject. It all depends on what kind of paint is used. One type of paint will need to be dry about 90 days before cured completely and other types of paint you can buff after 12-24 hours. So the answer to the original question is: What kind of paint did you use? And did it have a activator?

Thu Mar 29, 2007 6:02 am

I’m planning using an Acrylic Enamel (Valspar Suncryl 325 with hardener). I didn’t actually paint the car yet. I plan to do so tomorrow. I applied the sealer primer last Friday. I wet sanded out the nibs in the sealer primer with 600 grit.

I’m going to shopvac the hell out of my garage tonight and hope that it cuts down on the nibs.

I figured that I would wait until next week and then color sand the paint.

Thu Mar 29, 2007 8:39 am

It should be fine to sand and buff the car in a week. I see no reason why you shouldnt be able to.

Thu Mar 29, 2007 4:51 pm

If I were you I would read the primer sealer can. Most don't require sanding if you apply color right after you spray. Some might require a complete scuffing after a weeks curing time. Good luck.

Thu Mar 29, 2007 5:30 pm

I painted a pop top on a camper once during the afternoon, and these damn bugs (look likt little tumbleweeds, yet in bug form) kept sticking to the top. After I thought it was dry (3 weeks later) the little bastards kept sticking to the paint. It is amazing how long it can take for paint to cure perfectly...