Sealer

[Arnold Cunningham]

As part of teaching myself stuff, I've just had a go at spraying my defender in 1K basecoat & lacquer.
I'm not aiming for perfect - the panels are all wonky, it's a defender, but I'd like it to be presentable.

All the repairs and prep I did - I'm happy enough with. However, it now looks like it's been repaired before and when they did it, they didnt prep the surface properly - this means when I spray, the edge of the "old" job wrinkles.

Found this out yesterday, so have just wet sanded it all smooth again, much further back, and then shot some primer on. Same thing.

I really don't want to have to strip the whole tub back to bare, is there any product that I can use to bind/seal the poorly applied previous job to stop it wrinkling up on me? I know it won't be perfect, but as long as it doesn't wrinkle up, I'll be happy enough.

Thank you

What happened

What I found when I sanded that bit

[Arnold Cunningham]

Would this fix it?

https://www.churchill-paints.co.uk/churchill-paint...

[paintman]

Not a previous prep problem.
It's a problem of a high solvent content paint reacting with what's already on the vehicle.
Unsurprisingly spraying too thick a coat makes the issue worse.

Note that the TDS for the Churchill one specifies use of a 2K primer.

Barcoat is another sealer/isolator. Been around for years.
www.ultrimaxstore.com/files/ww/Products/UPOL%20Bar...

Edited by paintman on Tuesday 3rd May 19:35

[Arnold Cunningham]

Where I sanded down and put a super thin coat on, it’s still lifts at the edge. So I guess I’m a bit stuck. I’ll give barcoat a go and report back.

Thank you.

[paintman]

Arnold Cunningham said:

Where I sanded down and put a super thin coat on, it’s still lifts at the edge. So I guess I’m a bit stuck. I’ll give barcoat a go and report back.

Thank you.

Fingers crossed!

[Arnold Cunningham]

I do think there is a previous prep issue too - in some areas I peeled the old paint off in sheets. No kidding. I thought I had got all the badly prepped areas, but when I look closely here, I can see that glossiness under. So maybe a combo of old bad prep with poor adhesion, high solvent paint and me layering the primer on a bit thick.

Or is my technique solely to blame?

[paintman]

Not what you want to hear, but based on what you've just said I'm inclining to taking it back to bare metal & starting from scratch.

Did the bonnet & decker of my RRClassic last year & there were so many layers I did exactly that.
That way I could be confident that what I put on will stay on & be compatible with everything else.
But with the exception of the colour coat ( clear over base metallic) I use 2K.

Sanded to bare with 180grit discs on a DA sander connected to a Henry to deal with the dust. Didn't take that long.
.

Edited by paintman on Tuesday 3rd May 21:30

[Arnold Cunningham]

The big flat areas it was pretty close. It was just these bits that I skimped and am paying the price. Annoyingly can’t fit the detail sander even in this bit. Hand only. But I’ll drill the rivets out to make it a bit easier.

[Arnold Cunningham]

In progress

[paintman]

Arnold Cunningham said:

In progress

Use an etch primer on the bare metal before priming.

For large areas I use a 2K etch from a spraygun but if you want to stay with 1K I also use U-Pol's Acid8 aerosol on small areas where the metal is exposed - I do a lot of caravan stuff - & it's also available in tins for spraygun use.

[Arnold Cunningham]

Yes, I have etch primer already.

Don’t have an air hood, or the compressor capacity to supply it, I reckon, to do 2k.

[Arnold Cunningham]

Bit better. Looks good in the flesh, looks a bit orange peely in this pic, but up close it looks decent

Edited by Arnold Cunningham on Monday 9th May 07:54

Edited by Arnold Cunningham on Monday 9th May 07:56