Color sand all panels?

[ryanmctee]

This may sound like dumb question, but there it goes: Do I have to color sand ALL my body panels? I painted my truck in pieces inside my garage. Squirted three coats single stage urethane, then followed up with two coats of clear. For the most part, the truck looks great. Had some dust nibs in the hood (since I painted it on sawhorses and it was flat), which I have already sanded out. The doors I ended up running some of the clear, so I sanded those out. The front fenders look perfect. The cab for the most part looks perfect. The bed has a couple of small imperfections. My question is can I 'spot' sand? I'm going to cut and buff the entire truck, but just questioning if I need to SAND everything; or will the cut and buff take care of the very minor imperfections?

Heres some pictures just after paint if it helps - the pictures of the hood are before and after sanding.

Thanks in advance - Ryan

[hugger6933]

to my understanding the cut part of cut and buff is the sanding. I think if you were to sand only spots that those spots will show back up after the buffing

[Glorybound13]

I agree with Hugger. The cut is the sanding. It "cuts" down any imperfections that are in the clear so that when you're buffing, you've got nice, smooth clear to shine up. I would suggest wet sanding and buffing everybody panel, but, I'm not an expert.

[ryanmctee]

Thanks for those replys. BUT, if the panel doesn't have any imperfections, is it still necessary to sand? I'm thinking of at least hitting those panels with some rubbing compound on a wool wheel and seeing what they look like. If they don't look right, I can always go back and sand them, then buff again.... Right?

[HuggerCST]

Right. You don't have to sand/buff every panel, but after you sand and buff one, and see how slick it is compared to the unsanded/buffed, you will probably want to keep going.

[ryanmctee]

Tthanks hugger, but I think I have you confused. Sorry. I am going to buff all panels, just may not sand all. Some don't have any orange peel or imperfections at all. But I am going to buff all panels.

[67swb72klb]

u could just sand the lowers with the last grit you use like 2000-2500

[faribran]

the good panels may appear to NOT have orange peel.. but if u hit them with some paper you will be surprised... but i like your plan.. you can always come back and sand if need be.

[HuggerCST]

Originally Posted by faribran

the good panels may appear to NOT have orange peel.. but if u hit them with some paper you will be surprised... but i like your plan.. you can always come back and sand if need be.

I agree. Even though the fenders look great, I can see a little orange peel in the glare that could easily be slicked out by sanding/buffing. I'm not picking on your paint job, every paint job has orange peel to some degree. Like hugger6933 said, I think you will see the difference once you have buffed the hood, (compared to the fenders) but maybe not. I guess I assumed that you would sand before buffing because that's my process, but everybody has their own way that they like to do it, and as long as you get the results that you are looking for, then that's all that matters.

[GruntMoanCough]

Yeah, you can just nib sand and polish, I do it often if I'm trying to match existing/factory orange peel. Keep the nib sanding small, using the tip of your finger or the edge of a small block sander. Also, polishing alone won't take out the imperfections, as the polisher will kinda ride over them.
The only problem I can see, is if you block sanded the hood, rather than just hand sanded, then the texture may not match the rest of the panels. The sags on the door may cause a problem depending where they are.

[ryanmctee]

I really value everyone's input. I will more than likely, sand everything and finish up with 2500 grit prior to buffing. Just looking for the easy way out I guess. But hey, why would I do that after spending soooo much time on everything else right? This board is awesome!!

[CC69Rat]

2000 color sanding, compound, then foam pad. - and this is 12-15yr old paint .. Imagine what it would do to yours.

I'd say, light, light light 2500 all over. Then buff it. you'll see a difference, I promise. .. but it will work without color sanding, yes. It just all depends on how much time you want to put into it. I have about 6hrs in this one panel.

[ryanmctee]

Now that's what I'm talking about!!!! Pictures are worth a thousand words. That panel looks awesome. By next week I should have some pictures up of the finished panels, sanded and buffed. Just waiting on my 2500 grit paper to show up. NO ONE within 30 miles has any 2500 grit available....

[wickid demon]

Just remember when sanding, to stay away from the edges because paint is naturally thinner there. Good tip is to put tape where your body lines are and don’t sand there. Most curves flow themselves out better just go lightly with the compound and it should come out right for you.Ggood luck and take your time.

[CC69Rat]

Try Orileys auto parts if you guys have them there (?) or Napa usually keeps it in stock.

2000 would do it too, just super super light. It's going to haze your clear up, don't panic. The compund will bring it right back up.

You will be amazed at the shine. Look at the haze after you sand it and it has dried.. it will tell you exactly what needs to happen. If it looks like satin, move on. If it needs more attention you'll know it. Use a block, dont sand it with your fingertips. Keep it clean, keep the paper wet and cross over your strokes like you're blocking the panel.

Take your time ! Taping the edges is a good idea. The paint on my GMC got a little thin in places.

[ryanmctee]

Oriley's had only one sleeve of 2000, no 2500. Napa, only sells 2500 in 50 packs. Hard to believe huh? My 2500 should be in by next Tuesday, so I should be able to buff out by then. The hood and doors look very silkey with the sanding I've done so far with the 2000.

[gearheads78]

Use Meguires paper. It seems to have a lot less wild grit. Final with 2000 will be fine.

If you cut and buff the whole thing is up to what kind of results you want. OE look just nib it and polish it. I can see a ton of room for improvement from those pics if you want to have a slick job. Get a small 3M squeegy and clean the water off often to see the peel go away.

[CC69Rat]

Have you ever seen a shiney Orange? That's the idea. To shine and look 'slick' it's gotta be flat.

[ryanmctee]

Any thoughts on shooting another coat of clear, then re-sanding? Not that I'm going to to this, but I like all the input on this thread. Lots of good ideas here....

[gearheads78]

Originally Posted by ryanmctee

Any thoughts on shooting another coat of clear, then re-sanding? Not that I'm going to to this, but I like all the input on this thread. Lots of good ideas here....

Unless you screw something up its not needed at this point. If you were still painting you could do a "flow coat". When the paint is just dry enough to sand you block it all down with 600 and then right back in the booth for more clear. It makes for glass like paint when done right.

[theastronaut]

X2 on using Meguire's paper. If you're after a totally flat and slick surface, just using 2000 or 2500 won't "cut" it. I like to start with 1000 grit on a long/skinny durablock, then guide coat and resand with 2000 grit wrapped around a 3M soft pad. I finish up with 2500, sanding in a different direction than I did with the 2000. The 1000 grit is rough enough to cut the orange peel all the way out, where finer paper will "round over" the top of the texture without completely removing it.


Straight out of the gun with orange peel, notice the distorted reflection.




Partway through sanding with 1000 grit. You can see the texture being removed.




Guide coated and partially sanded with 2000 grit. The 1000 grit scratches are easily seen so you know when you've sanded enough to remove them.




Hazy shine after sanding with 2500. It doesn't take much to buff it out from here.




After buffing, the reflection is totally clear and free from distortion.




Posted via Mobile Device

[dfwright]

Marking for reference. Great info!

[screaminchevypickup]

Originally Posted by theastronaut

X2 on using Meguire's paper. If you're after a totally flat and slick surface, just using 2000 or 2500 won't "cut" it. I like to start with 1000 grit on a long/skinny durablock, then guide coat and resand with 2000 grit wrapped around a 3M soft pad. I finish up with 2500, sanding in a different direction than I did with the 2000. The 1000 grit is rough enough to cut the orange peel all the way out, where finer paper will "round over" the top of the texture without completely removing it.


Straight out of the gun with orange peel, notice the distorted reflection.




Partway through sanding with 1000 grit. You can see the texture being removed.




Guide coated and partially sanded with 2000 grit. The 1000 grit scratches are easily seen so you know when you've sanded enough to remove them.




Hazy shine after sanding with 2500. It doesn't take much to buff it out from here.




After buffing, the reflection is totally clear and free from distortion.




Posted via Mobile Device

I agree you need to start with 1000 grit then move out to 2500 or 3000!!! That way you don't spend 6 hrs on one panel
Posted via Mobile Device

[hugger6933]

Great explanation of the papers to use. The"cut and buff" is my least favorite part of job with the most reward

[theastronaut]

Another thing that helps is to use filtered water to reduce the introduction of stray grit.





All of those black specs would have been ground into the paint, causing random scratches that are impossible to buff out. If you do get scratches that won't buff out, mark them with a black sharpie marker and sand over the scratch with 2000 to remove it. The sharpie ink in the scratch will show you when to quit sanding, so you don't remove too much material.





I also like to hang the hood up so the water and sanding grit can easily drain off- less risk of grinding the sanding grit and stray dust/grit back into the paint.