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Sandpaper and guide coat

3K views 21 replies 14 participants last post by  Chevynut 
#1 ·
I'm getting ready to buy stuff for the next phase of my paint preparation, which I hope to start before too long.

I'm ordering a set of K-blocks to go along with the longboards and hand sanders I have. While I'm ordering, I thought I might as well get some more sandpaper and some guide coat.

Before applying the first coat of PPG K36 I blocked the last coat of Slicksand (where I needed more than one) with 120 grit paper. Then I shot the K36 and it will stay like that until I'm ready for the final paint prep.

What grit sandpaper do you guys recommend for the next phase, and then the final blocking before paint? I was thinking maybe blocking the K36 with 220 next, then 400 for the final blocking. Does that sound right?

What do you guys like to use for guide coat? I thought I'd try the 3M dry stuff, but it's $50!! Is there something special about it? I see some aerosol guidecoats (Duplicolor and Evercoat) for a fraction of that price. I have heard some guys just use black lacquer aerosol paint.

Any recommendations?
 
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#5 ·
I used the 3m guide coat, 220, 400, 600. I think the final block sanding will be depend on the color your are going to shoot. I asked the paint place what the final block should be, but i also painted black. I would ask the paint rep on to which should be your final block. And i just remembered, my actual final was a scuff pad 3m
 
#9 ·
what are you using in paint single stage or base clear? dose it have metallic? if you are using single stage i would go 500. if you are using base clear 600 is good for it and metallic or 700 metallic can find a scratch and stand up. i rather be over kill than sick :sign0020: when you get ready for paint and if you go with clear coat base coat make sure you ask for the hardener for the base! because if you ever scratch it or do any wet sanding and cut through the clear and re base in a couple years it will bubble up trust me i learned this the hard way:banghead:eek:ops got off track i like using lacquer primer qt about 12 dollars sands good and don't clog your paper like a rattle can will and it drys fast and can get red,black,Grey colors:anim_25:
 
#11 ·
Since I only work part time on my project I use SEM guide coat in rattle cans. I just do a section at a time. Saves me the trouble of cleaning a paint gun which we know everyone loves to do:sign0020:. Final prep, 400 grit before sealer.
 
#13 ·
My instructor Way back when always told me the paint need's something to grab hold of you con get to slick then it chip's easy.I have always stoped at 400 grit never had any problem's.Guide coat I guess I'v tried just about everything lacquer work's for me.:shakehands: :anim_25:
 
#15 ·
Most metallic paints are going to show 400 scratches. 600 is cheap insurance against that.

Chevynut, you said you're going to buy blocks. Didn't you long block your previous work?

And I would start at 180 grit and guide coat, progressing to 320, 400, and finally 600. If you need to re-shoot due to 180 grit sand throughs, you could start a bit finer on the re-shoot.

After you've gotten a good blocking with the guide coat, sanding with the finer grits will go very fast relatively speaking.
 
#17 ·
Chevynut, you said you're going to buy blocks. Didn't you long block your previous work?

And I would start at 180 grit and guide coat, progressing to 320, 400, and finally 600. If you need to re-shoot due to 180 grit sand throughs, you could start a bit finer on the re-shoot.
I have a 16" longblock with a handle and rubber pad, and another 9" one I built years ago out of a 1/4" thick aluminum plate. But for final blocking I think I'd like some better blocks.

Is it really necessary to take that many steps?
 
#18 ·
"Is it really necessary to take that many steps?"

I think so, and given what you want to accomplish underscores that.

BUT, once you've long blocked successfully with guide coat, you can forget the long block and guide coat and use a smaller and more flexible block, because what you're after at that point is finish and scratch removal. And that goes pretty quick.
 
#20 ·
Chevynut, one more thing. Once you've sanded with the 600 grit after successful long board blocking with guide coat, if you have no sand throughs you are ready to shoot color. But if you do, you have the choice of spraying more K36, and you can start sanding with a finer grit, say 320 or 400, then 600. Or you can shoot a sealer on it. Either DPLF with reducer, or K36 with reducer. You won't need to sand the sealer if you shoot the base coat on it within the time window.
 
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