clear butyrate over base-coat over butyrate?

[Scott Richlen]

Anybody spray auto base-coat color over a butyrate base and then top it all with butyrate clear?  Did it work or was it a disaster?  What did you do special?  I'd like to hear from people who have actually tried this.

Thanks,
Scott

[Mark Scarborough]

Scott,
I have not tried it, nor would I, the two systems are incompatable
HOWEVER,
there are some who are using a butyrate base, then getting just the toners from auto color systems, adding dope to the toner, spraying that, and then top coating with butyrate clear.

there are some things to be attended to in order for this to work and as a fairly experienced painter, I have grave reservations about it.

Randy Powell and others have done what i suggest,

[Randy Powell]

Basically, it doesn't work. The butyrate top coat will crinkle the urethane basecoat paint. I've used butyrate for base build up then urethane color basecoat and catalyzed urethane topcoat and that works fine (though it's a pain to repair). More recently, I've done what Mark Scarborough noted. Butyrate build up, auto toners added to butyrate clear then a catalyzed urethane topcoat. It's fairly light and not too much a pain to repair.

[EddyR]

There are two part spray cans of auto clear and they have the same problem. dope on top will crackle them.
Ed

[Clint Ormosen]

My simple rule is never put dope over anything but dope.

[Mark Scarborough]

My simple rule is never put dope over anything but dope.

agreed, but some have had success doing stuff different,, I avoid mixing, and especially dope over anything,,

[billbyles]

agreed, but some have had success doing stuff different,, I avoid mixing, and especially dope over anything,,

Hi Mark,

A few years ago when I still had plenty of acrylic lacquer colors I finished a few airplanes with that.  I did the usual butyrate dope buildup through the Polar Gray butyrate, then painted the acrylic lacquer colors starting with Porsche Guards Red, then went on with butyrate trim stripes, then finished with non-tautening butyrate clear.  Putting the lacquer on over the butyrate was no problem, but putting the butyrate clear on over the lacquer was dicey.  I could not get the clear topcoat very wet or it would "float" the underlying acrylic lacquer and give a very interesting looking effect (and not a good one.)

I don't use the lacquer anymore due to its unavailability and the aforementioned difficulty.  I agree with you in that I avoid mixing processes other than putting automotive polyurethane 2-part clear over most anything including dope, which works well.