What grit after re prime?

[Bwheeler287]

I primed the car with 2 coats of spi epoxy primer over bare metal/Edp/filler work followed by 3 coats of their regular build primer surfacer. I have blocked that down with 180. I have exposed the epoxy in a number of places to get rid of the powder quite coat I used. Only exposing bare metal on some edges where I got a little wild

this indicates to me that the surface is flat as I didn't hit any bare meteal before getting rid of the guide coat. There is one or two minor low spots that I think another prime will take care of and maybe some glazing putty to hit a few pin holes.

Questions for after the reprime:
since I believe it to be flat, should I reprime and go straight to hand wet 600?
should I reprime and block it once more with 320 I have a roll of then go to 600 wet by hand? Will there be enough primer to do that?
or am I totally incorrect and there's another way I should go?

[dhutton]

No need for 600 wet as far as I know. 400 dry is good enough for just about any quality basecoat. 320 if it is a solid color.

Don

[Bwheeler287]

im doing a metallic color, am I correct that I could go from a fresh prime straight to 600 though? Or do I need to hit it with something coarser first?

[dhutton]

400 should be fine for metallics but if you insist on going 600 I personally would block with 320 first. I am sure there is more than one opinion on this.

Don

[Bwheeler287]

Definitely not insisting, just a novice painter trying to get it straight in my head what i can and can't get away with

[GTOtzel]

If you are doing a urethane base/clear go 600 wet. If you do 400 you will see sand scratches. Do 2-3 coats of primer and guide coat block with the 320 then wet sand with 600. If you are not baking the car give it as much time as you can to dry. You want to allow it to shrink back as much as you can before sanding.

[minendrews68]

All good and accurate information.

[dhutton]

If you are doing a urethane base/clear go 600 wet. If you do 400 you will see sand scratches. Do 2-3 coats of primer and guide coat block with the 320 then wet sand with 600. If you are not baking the car give it as much time as you can to dry. You want to allow it to shrink back as much as you can before sanding.

If you use a quality basecoat 400 sand scratches will not show in my opinion. Cheap basecoat will likely show 400 scratches.

Don

[Bwheeler287]

Let me ask this, after I reprime and block again with 320 then 400 or 600 wet (verdict is still out on that, I will be using either deltron or chromax basecoat) how far do I go in places like the door frames, door jams, tulip panel areas etc...? All those lumpy uneven areas from stamping wrinkles and such. Do I go all the way to 400-600 wet as with the rest or can I cut back in those areas to say maybe a scuff pad?

[dhutton]

I like to do the door pillar area same as the rest of the car but the other less visible areas I use scuff pads. Again, you will get multiple answers. What color are you painting?

Foam sanding pads are another option.

Don

[Bwheeler287]

I like to do the door pillar area same as the rest of the car but the other less visible areas I use scuff pads. Again, you will get multiple answers. What color are you painting?

Foam sanding pads are another option.

Don

It will be a dark grey of some nature. Something charcoal ish. It will be metallic. Will also use a good basecoat as mentioned

as you mentioned the less visible areas would be what I was referrring to. Jambs I'll do the same as the rest of the car but areas that essentially won't ever be visible until disassembly, let alone under sunlight, it seems a bit excessive to go 400-600 wet

what scuff pad would you use, red? Or finer. I mistakenly got a box of grey laying around, those seem to be pretty fine like in the 600-800 range

[dhutton]

It will be a dark grey of some nature. Something charcoal ish. It will be metallic. Will also use a good basecoat as mentioned

as you mentioned the less visible areas would be what I was referrring to. Jambs I'll do the same as the rest of the car but areas that essentially won't ever be visible until disassembly, let alone under sunlight, it seems a bit excessive to go 400-600 wet

what scuff pad would you use, red? Or finer. I mistakenly got a box of grey laying around, those seem to be pretty fine like in the 600-800 range

If you have the grey I would use them.

Don

[Bwheeler287]

That will certainly save some time, as well as create a use for the grey pads I wound up with.

I appreciate the help.

[slow93z]

Spraying a metallic can be a little tricky with sand scratches, and metallics laying into a scratch and bunching up. Also are you spraying a sealer before your base coat? Blocking with 400-600 with a sealer will most likely eliminate chances of metallics bunching into sand scratches . Even a "NEW" grey scotch bright can leave deep enough scratches on a blend panel to bunch up the metallics if your not careful.

[Bwheeler287]

As it sits now I blocked it with 180 and plan to reprime the entire thing with surfacer for probably two coats. I then plan to block it with 320 then go with probably 600 wet by hand if the 320 block goes well. If I don't sand through any place I was planning to not use a sealer. If I do sand through I figured I'd go ahead and seal it or touch up the sanded through area.

Would this be appropriate? It's all new steel so I am not worried about any type of "separation" between an old paint or anything like that.

[slow93z]

If you have blocked with 180 and your confident the work is straight, then we you re-prime to cover your cut throughs I would probably just go to 600, again that is only if your straightening is already finished and you are just smoothing the last coat of primer. If your trying to build the primer and block out any more highs and lows. Then blocking with 320 would be good and you could use sealer over that. What are your plans with the car? Will this be a show car?

[Bwheeler287]

If you have blocked with 180 and your confident the work is straight, then we you re-prime to cover your cut throughs I would probably just go to 600, again that is only if your straightening is already finished and you are just smoothing the last coat of primer. If your trying to build the primer and block out any more highs and lows. Then blocking with 320 would be good and you could use sealer over that. What are your plans with the car? Will this be a show car?

It will be show quality (meaning I'm not going for a ridler award here lol) but driven a lot, and driven hard. No trailer queen. Being built specifically for my wife and I do do the power tour.

I'm pretty confident (famous last words) that it is straight. I broke through to the epoxy in a ton of places but almost no where to bare metal in the center of a panel. Some spots on the edges where I got a little sloppy with my block and got to metal is all. There was only one spot I felt the need to add some glaze for the purpose of filling a low spot I missed. Any other lows that can still be seen are very very minor and I feel a re prime with get those no problem. If I was willing to sand more an open up the epoxy more I could likely get rid of them. That's why I was think a block session with 320 would add the extra refinement and verification that it is indeed straight and filled any of those remaining lows.

Any other areas I added glaze were to fill pin holes that didn't sand out. Ones I had missed in the filler work.

Is there a need for sealer if this plays out like I hope it will?

[slow93z]

Well cool. Should be a very nice car. I think a 320 blocking or even 400 would be fine and if you break through again just spot prime those spots.....and I am not sure what your squestion is about the sealer. Sealer helps with filling in minor scratches or pin holes right before your spray. It is applied wet on wet which means you sprat the sealer and once the desired dry time has been met then you spray your color on top of it with out scuffing or sanding. It's basically used as a just in case method although it is not a must in some cases.

[slow93z]

In theory, if you went 600 wet, you could spray your color over that, but if your 600 wet didn't get out the 320 scratches then you could have issues with your metallics lining up in the sand scratch. So the sealer would cover the scratches that might have been missed.

[Bwheeler287]

In theory, if you went 600 wet, you could spray your color over that, but if your 600 wet didn't get out the 320 scratches then you could have issues with your metallics lining up in the sand scratch. So the sealer would cover the scratches that might have been missed.

Ahh "covers scratches that have been missed". Something that I never thought of.

I think it's pretty ineviditble I will miss some. So sounds like sealer may be a wise choice for me.

I'm going to have some leftover black spi epoxy primer that can be reduced and shot as a sealer. Should I get some gray sealer instead? Will be spraying the car a dark gray metallic color.

[slow93z]

The black epoxy sprayed as a sealer would be easier to cover with a dark grey metallic. Meaning it would take less coats of paint to cover, I'd say if your epoxy is compatible with the paint brand your spraying then just use that as your sealer. No need to spend money just to get grey. What brand paint are you spraying?

[Bwheeler287]

The black epoxy sprayed as a sealer would be easier to cover with a dark grey metallic. Meaning it would take less coats of paint to cover, I'd say if your epoxy is compatible with the paint brand your spraying then just use that as your sealer. No need to spend money just to get grey. What brand paint are you spraying?

The most available brand to me is ppg. I'll be using the good stuff. Deltron "dbc" i think it is. Correct me if I'm wrong. I will not be using the lower line Omni

[Rucumn]

Avoid using a wet on wet sealer approach with fine metallic base coats. Yes guys do it and some guys have the right gun and thin the sealer just right, but I don't recommend wet on wet application. If you must spray a sealer, then plan to wet sand it with 500-600 grit minimum for fine metallic base coat.

Otherwise you will see an ever so subtle texture "grain" under your clear coat as the sealer will leave a small orange peel and the fine metallics will orientate around the highs and lows and reflect the light differently.

Also, if you are planning to go metallic base or tri-stage, consider having an experience painter by your side to teach the proper technique. You really need to fan out your spray pattern and dial your settings just right.

[slow93z]

I will respectfully disagree with previous comment about sealer

[Rucumn]

I will respectfully disagree with previous comment about sealer

Can you share the reducer amount, gun settings, and specs you use to spray the sealer? It is not for the inexperienced if you want a top quality job.

[Bwheeler287]

I got the car re primed today with spi regular build surfacer. I plan to block with 320 first then go from there. Hopefully the blocking will go faster this round as it should be substantially straighter than the first time knocking it down with 180

[Bwheeler287]

320 block is done. I'm glad I did it. I feel like it added an extra level of refinement to re prime it and hit it with 320. I still had some break throughs but not near as much.

I'm about half way done wet sanding with 600. It's going quite fast as I really spent a lot of time doing a thorough job with 320

[chevelletiger]

Buy some 3m powder guide coat,rub it on and wetsand 600.
This will give you the best results.

[chevelletiger]

Btw,i think you need to prime and block a couple more times before wetsanding.
Your still new to bodywork,and even thou you
Feel its straight,its better to block and prime a couple more times before wetsanding.
You stated its going to be show,so i would keep sanding.
I know most dont like hearing that,but its the hard truth!
Thats why its called body work ;)