What grit to use?

General Discussion. Make yourself at home...read, ask and answer!
Should this post get stickied?

Yes
626
93%
No
22
3%
I don't care, I already know how to sand.
28
4%
 
Total votes : 676




Non-Lurker
Posts: 5
Joined: Tue Feb 05, 2008 10:07 pm
Location: Aurora, Co
PostPosted: Mon Apr 21, 2008 10:39 pm
36 grit roloc on small dent before filler
80 grit to sand filler
180 finish filler before high build primer
180 first block on primer before second prime
400 wet before sealer
600 wet for blend areas
800 rarely but occasionally start cut on a run
1000 sand imperfections from basecoat, sand runs in clear
1200 flatten orange peel
1500 sand surface for factory orange peel look
2000 for scratches in clear coat
3000 trizac for easy polishing

Grey scotchbrite- Prep plastic for paint(with scuff stuff), o.k. for hard to sand blend areas, or for not burning through the clear, may be used on sealer or base for recoating.

Red scotchbrite- Prep new body panels for paint (best to seal over, but can be covered with basecoat) good for sanding before laying down stripes, o.k. for some jams.



Settled In
Posts: 15
Joined: Fri Apr 04, 2008 3:30 pm
Location: Indianapolis
PostPosted: Sat Jun 14, 2008 8:16 pm
Thanks for the advise. As a novice, I just replaced and painted the fender of a car I bought cheap, and probably would have botched the whole thing if not for yours and others help.
God Bless America and the Indianapolis Motor Speedway!
Image



Fully Engaged
Posts: 248
Joined: Tue Jul 29, 2008 4:01 pm
PostPosted: Sun Sep 07, 2008 2:29 pm
Can you go straight from 60 or 80 to 220 before priming? Or should I use something like 150 before the 220?



Top Contributor
Posts: 4397
Joined: Sat Jan 01, 2005 7:55 pm
PostPosted: Sun Sep 07, 2008 2:44 pm
enkeivette,

What did you sand the surface with already?
What do you have in mind for a primer?
A man can do all things if he but wills them.



Fully Engaged
Posts: 248
Joined: Tue Jul 29, 2008 4:01 pm
PostPosted: Sun Sep 07, 2008 4:02 pm
The primer of choice for Corvette bodies seems to be an epoxy primer. I've gone over the whole car with 80 grit with a DA, 60 grit in a few areas.



Top Contributor
Posts: 4397
Joined: Sat Jan 01, 2005 7:55 pm
PostPosted: Sun Sep 07, 2008 4:18 pm
I would definitely epoxy seal it first. And those grits are perfect to shoot
over.
A man can do all things if he but wills them.



Fully Engaged
Posts: 248
Joined: Tue Jul 29, 2008 4:01 pm
PostPosted: Sun Sep 07, 2008 7:40 pm
You mean I can spray primer right over the 80, without smoothing it out to 220?



Top Contributor
Posts: 4397
Joined: Sat Jan 01, 2005 7:55 pm
PostPosted: Sun Sep 07, 2008 11:46 pm
Depends on the "primer." For epoxy primer 80/120 is fine. Think
of the epoxy more as a barrier/sealer coating (for now). Bondoking
and dt196 will be of more help than me. But the idea is fairly simple.

From where it is now, i'd block sand as much off as possible.
Shoot (roll) two coats of this sealer coating. And depending
on the epoxy (********** black epoxy is great), you can have a better
idea of what the surface looks like.

At the moment, the vette is sorta like this:
Image


2 coats of black epoxy and all the imperfections can show:
Image


Or not show. You'll have a better idea in one color...
A man can do all things if he but wills them.



Settled In
Posts: 90
Joined: Sun May 07, 2006 5:06 pm
Location: Columbus, Ohio
PostPosted: Mon Sep 08, 2008 9:22 pm
enkeivette,

I've lost track how you've stripped your vette. Here's the process that I use.

Clean the car with wax and grease remover.

Start stripping with 40 grit on a da to remove all topcoat paint, leaving the primer that is on top of the glass.

Now sand off all primer down to bare glass with 80 grit on a da.

Now do all body work with appropriate materials (SMC compatible in your instance). Body work finished in 120 grit.

Now da the entire car with 120 grit.

Next, blow the car off REAL well with high pressure, mask and tack wipe. You are now ready for epoxy (yes I use ********** black) Notice I don't use any wax and grease remover on the bare glass before the epoxy. It will soak in and take a good long while to leach out. Spray 2 good wet coats.

Next, 1 or 2 days later, spray a couple coats of poly primer. I like Slick Sand. No need to sand first as you are within the 7 day window with the ********** epoxy. The next day, guide coat and block with 120 grit. If you still find some imperfections, they can be fixed with an application of a finishing putty. I like Easy Sand.

At this point it is reay for urethane primer, which you said you were going to have your painter do.

Any other questions, don't hesitate to ask.

Dan



Settled In
Posts: 79
Joined: Sun Sep 14, 2008 8:12 pm
Location: Paris,Il.
PostPosted: Sun Sep 14, 2008 8:32 pm
What grit to use before primer?
As "fine" as you are capable of keeping it straight(correct conture).
Imagine this: lay those sand scratches on their side and magnify.
Now lay a thread,if you will,all along those peaks and valleys,with no air gaps anywhere.
Remove that thread and pull them both tight.
The longest will probably be from the "finest" sand scratches.
Thus giving more of a "sanded surface",which will allow for better adhesion,and better color holdout.
And right before you prime?Run your finishing DA over the entire area that you are priming(be careful!),eliminating those "linear" scratches and installing an orbited scratch.This simple(but important!) step will eliminate those "straight line" scratches that usually show up when the job is finished and gone.
Strandberg Auto Rebuilding,Inc.
PreviousNext

Return to Body and Paint

Who is online

Users browsing this forum: magee84 and 132 guests