Stupid question and please confirm please

2

20mercury

Promoted Users
Ok, read perfect paint job, tech manual, forums and this is by far the best body/paint forum with super knowledgeable folks willing to help. Thanks!

I need some confirmation on plan to paint 68 and 72 Corvettes while waiting on 24hr >65F weather, please. First auto paint job for me.

I did all the body work on these 2 Corvettes with VPA as filler, SPI epoxy first coat, SPI 2K multible times, 150g-220-320-400-600grit sanding and still going through to the first white epoxy in spots ( getting white dots). Usually put 2 coats of std build 2K at a time.

So, I am thinking 2 coats of std 2K is not much so sand thru's to the epoxy should be expected. Good news is I am getting "fewer" white spots (sandthru's) every cycle, but I am thinking this is sorta like that guy that kept pushing the rock up the hill and then it rolls back down, hmmm.... maybe time to ask questions and review?

If I understand correctly, I need a nice even 600 sanded coat of 2K (both Corvette to be a metallic OEM color Diamont: BC/SPI euro) before putting on a thin coat of SPI epoxy as a sealer, then base then clear. This means "NO white spots" sand thru's, right?? before next step.

So question please, I need more coats of 2K and sanding cycles right? and keep going, right? and maybe start with high build 2K for the next paint project AND I need a nice complete even coat of 2K before next steps SPI epoxy sealer/bc/euro clear???

Any and all suggestions are welcome. Much Thanks.
 
20mercury said:
So question please, I need more coats of 2K and sanding cycles right? and keep going, right? and maybe start with high build 2K for the next paint project AND I need a nice complete even coat of 2K before next steps SPI epoxy sealer/bc/euro clear???

Any and all suggestions are welcome. Much Thanks.
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I'm a hobbyist and amateur, so take my thoughts in that context. I agree this site is the best there is.
I'm sure others will add their thoughts soon.

The fact that you are getting fewer spots each time implies that you are building the lows up to the highs, which is the goal.
At some point it may be absolutely good to go, even with a few spots (natural high of a curve etc.) A lot depends on the size of the block and your technique.
You didn't mention guide coat. Have you tried that? Some use a contrasting color rattle can misted on, some like the powder.
Guide coat will tell the truth. You can search the site and there are many discussions about it.

Another tip that I've seen here is to wipe Wax/Grease remover on the area and then catch it in the light and see if you can spot imperfections in the sheen.
Another is to go ahead with the sealer coat, which will be a consistent surface, then close your eyes and lightly run your fingers over the surface and see if you can feel imperfections. If they exist, just those areas can be addressed with more 2K.
Don't be alarmed if you spray the epoxy guide coat and it looks different or "splotchy" over the exposed spots. That is normal and will not show up in the base.

One newbie to another - take it for what it is worth. Good luck!
 
What size tip are you using for the 2k build primer?

I shoot it with a 2.0 tip and generally shoot 3 coats on the first round. As you have seen, most of it ends up on the floor.

Guide coat is your friend during the blocking process. Also, and this is important, use a suitable length sanding block for the panel and do not press too hard on it. This is a common mistake and easy to do because sandpaper is expensive so we try to make it last. Keep a firm even pressure on your sanding block, sand at a 45 degree angle to the panel, and change your sandpaper as soon as it quits cutting. I sand in one direction from left to right and then reverse direction, thereby sanding in an X pattern.

When pressing too hard you can actually flex the panel and defeat your whole purpose.

Blocking a car is a lot of work, so learning to do it correctly will be a big benefit to you. You may feel like you are wasting sandpaper at first but keeping sharp paper on your block is the key to keeping a firm, steady pressure.
 
Much Thanks for the replies.

Using a 2.5 tip TCP Global HVLP gun for 2k

Sorry I did not mention guide coat, I lightly sprayed with Sata NR1.3 some lacquer paint from Summit, bought
some more spray can guide coat and will try that next and instead. I think you have to sand harder to get this lacquer off which may mean something.

Wet sanding and dry sanding with blocks at 600 now. Do you wet sand or dry sand 2K?

Shooting 2 coats, will try 3 coats
and likely pressing too hard on blocks or sanding too much to get the lacquer guide coat off.

Yep, lot of work for sure, but what I got at this point is some super smooth straight surfaces with 600 grit scratches, just still popping up white spots but less white spots.
"The fact that you are getting fewer spots each time implies that you are building the lows up to the highs, which is the goal." Makes sense.

Thanks again for the advice and feedback.
 
I like the 3M Dry Guide coat. One container will do at least 3 completes so it lasts quite a while.

When block sanding with the coarser grits, I sand it dry. When ready for finish sanding grits I switch to wet.
 
You're working yourself harder than necessary by sanding with anything finer than 180-220 before more 2K. I would suggest getting some dry guide coat. It is far superior to lacquer, which tends to plug the paper, costing you more sandpaper. Block with 180-220 until the guide coat is gone, no more. Once you are pretty sure it is straight as you want it, then you can spray 2 coats, guide coat, and start with 320. Sand until guide coat is gone, guide coat again, sand wet with 600 until 320 scratches are gone. There are many procedures that will work, but this is how I normally do it. If you want to limit the amount of blocking rounds on the next one, get some polyester primer and spray it after epoxy and filler work. That 2.5 tip gun will spray it.
 
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1. Start with 3 coats 2k.
2. Guide coat. I just use very thin mist of cheap rattle can black.
3. Block sand with light touch, 180 or 220 grit.
4. Guide coat and block again.
5. Apply more coats of 2k as necessary and block as necessary.
6. You are done blocking when A) your guidecoat sands off evenly, or B) your bag of shits to give is completely empty.
7. Spray with once medium coat 2k. This will fill in all your sanding scratches.
8. Wet sand with 600. This is the first wet sanding step and no scratches to worry about cancelling out.
 
Lizer said:
1. Start with 3 coats 2k.
2. Guide coat. I just use very thin mist of cheap rattle can black.
3. Block sand with light touch, 180 or 220 grit.
4. Guide coat and block again.
5. Apply more coats of 2k as necessary and block as necessary.
6. You are done blocking when A) your guidecoat sands off evenly, or B) your bag of shits to give is completely empty.
7. Spray with once medium coat 2k. This will fill in all your sanding scratches.
8. Wet sand with 600. This is the first wet sanding step and no scratches to worry about cancelling out.
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I'm definitely a 6B kind of guy!
 
Lizer said:
1. Start with 3 coats 2k.
2. Guide coat. I just use very thin mist of cheap rattle can black.
3. Block sand with light touch, 180 or 220 grit.
4. Guide coat and block again.
5. Apply more coats of 2k as necessary and block as necessary.
6. You are done blocking when A) your guidecoat sands off evenly, or B) your bag of shits to give is completely empty.
7. Spray with once medium coat 2k. This will fill in all your sanding scratches.
8. Wet sand with 600. This is the first wet sanding step and no scratches to worry about cancelling out.
Click to expand...
I'm with v8, 6.b is where I always end up with every panel
 
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