clear coat rub down

[NutmegCT]

I used 3M rubbing liquid on the 50 year old paint. Looks much improved.

View attachment 27971

But on some pocked and/or rusty spots I sanded, primed, then used PaintScratch base and clearcoat.

Now after several days I'm trying to rub it down for a shine. No shine so far, so I'm asking how exactly to do it.

Here's what I did: 3M on an old t-shirt. Rub 'til dry, then wipe off with another t-shirt. Then polish with electric buffer and terry cloth cover. No shine.

Also tried using electric buffer for all the steps. No shine. Surface still feels "gritty" (not smooth) from the clearcoat - like it's not being completely removed.

Any suggestions out there?

Thanks.
Tom

 

[Bayless]

Not familiar with PaintScratch but with most materials unless catalized you have to wait a while for it to get hard enough for polishing if it ever does. Even then it usually requires color sanding before any of the compounds will do any good.

 

[NutmegCT]

Thanks for the help. Following the PaintScratch instructions, I waited four days between final base coat and first clear coat. Then waited another five days after last clear coat, before trying the rub down.

One thing that would help - what specific rubbing compound (manufacturer, name) do you use on new clearcoat? I'm using 3M Perfect-it II (05973) liquid rubbing compound, but maybe that's too fine for the initial use?

Tom

 

[BigGreen]

Your old paint won't have clearcoat, its the deep dirt that makes it dull
The 3M 05973 is a heavy compound for 1200 Gritt scratches
This compound should be used with a foam pad on a machine
That combination will make the compound lose its strength

T shirts and Terry pads are too rough in my opinion
Try using all the 3M stuff in combination with low rpm
The one with the yellow cap and yellow pad should do fine

Hans

 

[NutmegCT]

I got a reply from the paint company. They suggested wet sanding the clearcoat with 1000 grit paper, before using the rubbing compound.

Looks like a big improvement. Here's the untreated clearcoat:

View attachment 27993
And after wet sanding and compounding:

View attachment 27994
Wish they'd said that in the original instructions!

Tom

 

[PAUL161]

Tom, didn't you say 50 year old paint? The manufactures didn't use clear coat 50 years ago that I know of, or was the clear coat done more recently? The use of a thick clear coat started out on rocker panels in the 60s. By the way, the wet sanding and compounding looks great I might add! Nice work. PJ

 

[NutmegCT]

oops - guess I wasn't clear.

I had about a dozen spots around the car that had damaged original paint, and surface rust. I sanded to bare metal, primed, then several light layers of PaintScratch base coat, followed a week later by several layers of clear coat.

It's that "new" clear coat I'm having trouble with. In some spots, the 1000 wet sanding (by hand) followed by 3M compound (by hand) works great. But in over half the areas, that same procedure results in blotchy areas.

So I guess I'm wondering if there's more to it than 1000 wet sanding, followed by 3M compounding. I've seen many videos of guys either hand rubbing with 3M, or wheel buffing with 3M, on new clear coat. But they never have any problems. It's like (1) squirt the 3M on the surface, (2) move the wheel across it a few times (3) voila! perfect glossy surface. They don't explain what cover (foam, lambs wool, microfiber, terry, etc.) is on the wheel, what speed, or how they prepped the surface before using the 3M.

Even my "success" in post #5 above has blotches in it.

grumble grumble

Thanks.
Tom

 

[PAUL161]

When I had the B painted, after wet sanding by the paint shop, they applied a clear coat. I was told that when power buffing, it's very easy to burn the paint. The clear coat set for 24 hrs before they buffed it. I guess that's why they move so fast over the car with the buffer. A custom car shop painted the car for me. The finish is immaculate! PJ