Larry... sage advice.
Yes, I will send your message via my time machine to the fellow who in the 1970's sprayed
Auto Enamel over the factory dope and cotton, with CC's to the guys since who have used:
dope
spray cans
stitts
and
??? stuff ??
Trying to patch the wings ever since.
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But Seriously: Yes, my trying to use dope to patch flaws in the DuPont enamel over dope has been frustrating,
and way more (toxic) trouble than it was worth.
I've been trying to do exactly what you warned against... thinking some how I wasn't !
The dope solvents bubble up anything that came out of a spray can ( which had xyzlene solvent). xyz indeed.
I was reluctant to use epoxy and micro balloons.. but clearly this is a better way to go.
it is sandable, and can be touched up with more enamel, less toxically and with less trouble than dope.
I guess I was afraid the epoxy would bond the cotton to the mahogany underneath and make problems later,
but the cotton is already sealed and that clearly can't happen.
Had the stuff all along, but was afraid to use it. Back to square one.
The whole paint system - on the wings- is basically a failure. In places the cotton came unbonded and has been replaced.
I am not seeing any more of THAT. Thank god.
The enamel is peeling on the undersides, in spots, with red dope showing . Enamel is not flexing and so breaking - most everywhere in dibs and dabs... which is what I am patching.
Sanding has revealed that the cotton underneath is intact..So this is cosmetic eyesore that looks "scary" but really isn't.
So, from my point of view, anything I do is temporary and touch up, just to maintain "water tight integrity"
as they say on submarines :wink: and make it more cosmetically acceptable.
It really is putting paint on a pig, because the enamel will continue to crack .. simply because it is the Wrong Stuff.
Cooper - who used to own Ceconite back in the day - corresponded with the owner who made the original mistake
of using Dupont Enamel, I still have the letters from the 1970's in the airplane files. At the time, Cooper said the only cure was to strip the stuff off down to the fabric and start over.
Waaaaay to late for that now ! It is NOT time or cost effective to strip the enamel.. trying to save 67 year old cotton !
When it's time..( read next owner) the wings should come off, get shed of their covering, get a good once over, and then get recovered from scratch with modern materials .
If you follow the ceconite manual.. with a diluted coat of epoxy on the skin first.
I haven't read the Stitts manual.. different process.
But I am pretty damn sure that I don't want to swim in a sea of toxic solvents (Nitrate, Butyrate) or work with Urethanes
either !
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Meanwhile, I will do what I can do.
- Every failure is a learning opportunity-
I am learning so damn much !
