Buffing flat sanded clear coat

  1. My model of MX-5 is: mk2
  2. I’m based near: Prestwick
  3. I’m looking for technical help or recommendations on: buffing/polishing flat sanded clear coat__

I painted a wing on an old Jag using some aerosol paint and clear coat.
I’ve left it for a few days and flat sanded the clear coat to remove some peel.

Today I tried to polish it up using some compound but the compound seems to be sticking to the clear coat and is difficult to remove and therefore won’t buff up.

I’ve painted loads over the years and never had this problem before.
I’ve tried some G10 compound and also some T cut, but both are the same.

I don’t have an electric polisher so doing it by hand.

Any thoughts on what’s causing this or how to rectify it?

Thanks

My guess would be the clear coat needs longer to cure.
Was it a new can?

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Hi

Yeah, all new.

I imagine that temperatures and humidity were all reasonable whilst you applied both colour and top coats?
Also, did you go with the same brand for both layers?
I had a reaction with paint once because I used the wrong top coat.

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No issues with humidity etc.
The paint was mixed specially for the car, and the same company supplied the clear.
I’ll maybe leave it wet sanded for a couple of days and try again.

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Hi was it one pack (air dry) clear coat, or two pack (with the actuator button on the bottom).
I have polished two pack the day after, but one coat you may need a few weeks before it hardens fully as the base coat will also be hardening.
I would walk away for a few weeks and try again.

Hi
It was 1k clear…
When you say try again, do you mean leave it flattened and try polishing later?

Yes that is what I mean,let it fully harden first.

OK, thanks.
I usually use upol clear in a can, and it hardens quickly.
Would it be worth going over it again with some of that?

I would ask them about it.

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As Richard says, I would not spray over it until
It’s fully hardened, you will just delay the process.

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A lot of the can blurb would have us believe that the product dries sufficient to overcoat in a matter of minutes but I have noticed it can take days, depending on what paint, thickness of coat, etc.
Spraying extra layers exponentially delays the curing process, so even with high ambient temperatures could well take a week before you can depend on full cure for polishing.
I’ve had quite a few delays with small projects this year where lacquer in particular taking a long time to stabilise. I was convinced I had a duff can or a reaction to the paint below but it really is just a case of walking away for a few days.

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I found the fact sheet for the clear coat I used.
Says it can be polished after 24 hours…

True, but it also states that drying time is dependent on temperature, humidity and thickness.

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Location is also significant if VOCs are present, or a chemical reaction is required.
A small closed unventilated garage can double or quadruple drying/curing time.

A fan heater can be useful to warm the environment and circulate the air AFTER the paint is no longer in the least bit tacky.

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Last night I sprayed a test panel with the same base coat then cleared it with my usual upol clear, giving it 3 coats.
This morning the clear was dry and there was no stickiness and it polished to a mirror finish no problem.
The conditions were similar to when I painted and cleared the wing…
I’ve decided to start again.
I will flatten and remove the clear back to the base coat, then give it another couple of coats of basecoat and then clear coat with the upol clear.

I do appreciate all the help…
Thanks

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Sounds like a plan. Good luck. We’ll keep our fingers crossed for you. :crossed_fingers:

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Guys, just a quick update.
I sanded the wing back and started again, this time using the paint and clear from my usual supplier and it turned out great.
Thanks for all the help…

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