Zinc Chromate in 2005?

[Guest]

Re: Zinc Chromate in 2005?

Ray - I had thought I'd heard about an incompatibality between glue and ZC, but I've seen several ships covered using the Ceconite process (from the mid-70's) with a ZC primer. That's 35 years, so it must not be a terrible incompatibility! Am I incorrect in what I'm observing? - Mike

When not using epoxy you can use a paint called "dope proof paint" from Randolph (maybe ther are other sources) and put two coats of it over any primed part that will be glued to contacted the the fabric.

The paint is chalky white and stops the dope & glue solvents form lifting the primer. Without it it's kinda messy since the glue & dope dissolve the primer.

I saw a cub 3 years ago that had been recovered and had been primed with zc but no dope proof paint. The tubes were rusted and pitted like crazy and looked to me like it was due to the fact that the primer was basically destroyed and lifted off the metal by the solvents and offered no protection to the metal. It was so bad they had to replace the fuselage.

Dope proof paint is probably not used so often now with the availibility of epoxies.

Also as someone else pointed out the new version of the ceconite stc requires epoxy primer.

Dave

[mhorowit]

Re: Zinc Chromate in 2005?

When not using epoxy you can use a paint called "dope proof paint" from Randolph (maybe ther are other sources) and put two coats of it over any primed part that will be glued to contacted the the fabric.

Also as someone else pointed out the new version of the ceconite stc requires epoxy primer.

Dave

Excellent. Thanks - Mike