paint reaction

[bradfordian]

this is second time now, first time I thought it might have been because I polished the body before masking amd spraying but this time I didnt polish but same reaction.seems like the paint is melting the paint underneath and its splitting.

zero pure white with zero mclaren red.

[stevenoble]

I've had it once myself. Never got to the bottom of what caused it. Have you got any contaminants on the white before you sprayed the red? I know from experience that the Zero red is hard to get right..

[bradfordian]

Paint reacted, no contaminants.the white paint reacted as it went all soft and stodgey.also used zero primer.

[John18d]

bradfordian - it looks like the solvents in the MP4 red attacked the white.
did you spray on a heavy coat of the MP4 red??
just asking
John

[bradfordian]

Did a tack coat and yep sprayed a couple of heavier coats.

[John18d]

Bradfordian - when I used the "Zero" MP4 red paint I sprayed many very light coats until it colored up to achieve the correct opaqueness.
If you use heavy coats the solvents in the MP4 red attack the basecoat paint.
Try the technique out on a white plastic spoon
John

IT IS IMPORTANT TO USE VERY THIN COATS - ANY PLACE THE SOLVENTS CAN POOL THEY WILL ATTACK THE BASECOAT BEFORE THEY CAN EVAPORATE
John

[Veyron]

I got the same effect with heavy coat of MP4 over Tamiya primer on a plastic spoon test.

[MPWR]

Originally Posted by John18d

ANY PLACE THE SOLVENTS CAN POOL THEY WILL ATTACK THE BASECOAT BEFORE THEY CAN EVAPORATE

There are several significant reasons to never apply heavy wet coats of paint- especially solvent based lacquers. This is one of them.

Always using thin, light coats solves many problems in painting.

[klutz_100]

sometimes it's good to read instructions and small print

From the zero paint web page:

These are known as basecoat colours which require applying over primer and need clearcoating.

For further information on using Zero Colour Matched Paints please read the Zero Paints F.A.Q. below


APPLING[SIC] THE BASECOAT COLOUR
Depending on the colour supplied, you will need to apply about 2-5 light coats. (figure 6) Each coat will dry within a few minutes. DO
NOT apply Wet Coats, the paint will dry MATT (this is normal), just ensure you have even colour coverage. The final coat should be
applied in a criss-cross fashion to allow an even consistency of the metallic particles.

[rgriffs]

i agree with the previous replies, probably down to too much solvent doing the damage. i did exactly the same this week, with halfords paint, i suspect that i put too much paint on, this attacked the underlying paint. it is also cool here in the uk, so the thinners are less able to 'flash' off. another wrecked shell for me. i usually leave my painting till the days warm up a bit.

[stevenoble]

Originally Posted by rgriffs

i agree with the previous replies, probably down to too much solvent doing the damage. i did exactly the same this week, with halfords paint, i suspect that i put too much paint on, this attacked the underlying paint. it is also cool here in the uk, so the thinners are less able to 'flash' off. another wrecked shell for me. i usually leave my painting till the days warm up a bit.

Don't despair. You can simply strip the shell and start again. I strip almost any paints with Isopropyl Alcohol, which you can source at most hardware stores. Just fill a plastic container that has a lid (old ice cream tub is perfect) and immerse the shell in there with the lid on for a few hours till the paint softens. Then I simply scrub the shell with an old toothbrush to remove the paint. Sometimes takes a couple of soaks, but always works.
Don't know how you're fixed budget wise but if you can afford a Mr Dry Booth or similar you can paint in all weathers with no problem, as it keeps the painted parts warm whilst they dry. I've had mine a good few years now and I have to say that it was one of my better buys for sure

[klutz_100]

Originally Posted by stevenoble

Don't know how you're fixed budget wise but if you can afford a Mr Dry Booth or similar you can paint in all weathers with no problem, as it keeps the painted parts warm whilst they dry. I've had mine a good few years now and I have to say that it was one of my better buys for sure

or save yourself over 100GBP with something like THIS

Steve is 100% right though, after a decent airbrush, a dehydrator/dryer one of the best and most versatile pieces of kit in your workshop.

I bought a cheap dehydrator similar to the one above and simply snipped out the bottoms of a couple of trays to make a "chimney" that easily takes the Tamiya paint stand and a 1/24 body .