Question about sanding.

[aussiewannabee69]

This is my first attempt at body/filler/paint work so I don’t really know to much about it all.
I’m smoothing out the engine bay on a 69 coronet and have done the metal work, sprayed with epoxy then done the filler work. Once I got the filler down I blocked it with 40 and then 80. Then sprayed primer filler, blocked it with 120 then 240. Still have 400 to go and then was going to hit it with another filler primer.
My question is was I meant to sand the epoxy with a finer grit before I sprayed the filler?
Please let me know if I’m meant to add more steps in.
Also do I spray again with epoxy after the filler or is it sealer?

 

[aussiewannabee69]

Paint will be B5

 

[Motorcitydak]

The directions from the specific product you used can guide you a good bit. Best thing all that with can do is give you a great smooth surface for your B5. Paint is good at self leveling so a glass smooth surface isn’t strictly necessary. In fact you still need a decently scuffed surface for it to grab on it. Hitting it with 320 before paint is common. Also you can shoot sealer if needed but that usually is if your primer is old and you want new material for the paint to stick to. Again, reference your product instructions. You’ll usually reduce your primer with 5-50 percent urethane reducer.

 

[69L48Z27]

I didn’t follow all of it. I would not sand anything with 40.

From epoxy:
- Do your filler work, 80 then finish in 120
- Primer surfacer - 220/320/400
- If you got everything sanded out go straight to sealer and color.

If you have any break throughs you can spot prime, I don’t think I would do two rounds of primer for underhood unless you need to dig something out.

 

[dvw]

I believe your question was "should I have sanded the epoxy with a finer grit before spraying over it". As long as the epoxy was scuffed before additional top coats you will be fine. It only needs Scotchbrite. It makes an excellent sealer.
Doug

 

[zyzzyx]

Epoxy primer is the best, but if you apply it and let it sit more than three or four days before
top coating with anything you'll need to scuff it. It will become too hard and you won't get good
adhesion. Everything looks great on your pic's, but you have alot of orange peel. You need to
knock that peel down before top coating or it will look terrible. The rule of thumb is, 400 for
solid colors and 600 for metallics. And use a sponge between your fingers and the paper so
you don't put grooves in the epoxy. Any rub-throughs can be spot primed. When done, it will
look like glass! You've already done the hard work.

 

[aussiewannabee69]

I believe your question was "should I have sanded the epoxy with a finer grit before spraying over it". As long as the epoxy was scuffed before additional top coats you will be fine. It only needs Scotchbrite. It makes an excellent sealer.
Doug

Thanks. Forgot to mention that I scuffed it with a brown scotch brite pad.
It came up due to me reading a post on another forum that If you didn’t sand the epoxy prior to filler primer that scratches would show up.
Cheers Doug.

 

[aussiewannabee69]

Epoxy primer is the best, but if you apply it and let it sit more than three or four days before
top coating with anything you'll need to scuff it. It will become too hard and you won't get good
adhesion. Everything looks great on your pic's, but you have alot of orange peel. You need to
knock that peel down before top coating or it will look terrible. The rule of thumb is, 400 for
solid colors and 600 for metallics. And use a sponge between your fingers and the paper so
you don't put grooves in the epoxy. Any rub-throughs can be spot primed. When done, it will
look like glass! You've already done the hard work.View attachment 1336202

It came out like a bloody grey orange haha. I will have to play around with the gun settings a bit before the top coat. Yeah I did remove the peel. Really gotta find out how to spray flat. Save so much time. So go up to 600 on the primer filler?

 

[zyzzyx]

Yes, since B5 is a metallic. To make topcoats lay down flat, use an HVLP gun with about 30psi
and thin it for multiple coats. If you atomize the paint very fine, it will be nice.