Emron paint over Ceconite process?

[mhorowit]

Anyone have any experience with Emron paint over Ceconite? If I had to patch a wing covered in that combo would that be a problem? Will the Emron come off with the dope? - Mike

[Mark Julicher]

Re: Emron paint over Ceconite process?

Mike,
Dupont Imron is a urethane and when used straight up it leaves a hard finish. If used on Ceconite is ought to have a plasticizer additive to keep it flexible, or at least flexible longer...

There is at least one certified process to use automotive urethane over Stitts. This STC (belongs to Kenny Blalock who was then a collaborator on an improvement of his process which eventually became the Air Tech). Kenny's original process was Stitts through silver and then gray primer and then urethane. Nice finish but heavy. Urethane does not remove easily. MEK can do it, but MEK lifts about everything else too. Imron can be cracked peeled off dry if you have a lot of time on your hands. Results may vary here, and it is about easier to just recover.

Imron over Ceconite will eventually harden and crack - leaving ringworm or the dreaded cracks along the fuselage longerons. These can be "repaired" to keep out water by using clear Monokote (yup, as in model aircraft covering).

There are no rejuvenators for urethane, but MEK will lift an area and allow it to be repainted.

I think I am starting to babble here so I'll sign off and hope I partially answered your question.

[Ragwing nut]

Re: Emron paint over Ceconite process?

It used to be acceptable to do such until the STC holders got tired of people complaining about cracked finishes. The STC processes now cover everything thru and including color coats.

AirTech uses Ceconite fabric, not Stits as mentioned above.

More than likely you can peel the Imron from the dope. I have never seen anyone apply it where I could not remove it. Peel it back to make the repair, and then refinish to match what was already done.

Mike

[flyguy]

Re: Emron paint over Ceconite process?

Mike,
In my not so humble opinion, paint, is paint, is paint, and as I have said before, putting paint on a fabric aircraft is a exercise in futility. The repairs are extremely hard to do and usually look like crap and it ALWAYS cracks. I have had 3 Tcarts with paint on top of stits, et al., and I can assure you that it sucks. People just keep doing it; makes you really wonder. Just use stits all the way to the top and then you can always refinish, spray over, match up, and it WILL stick and look pretty good. IF you want a airplane to fly do it that way. If you want a glassy collectors airshow finish, do it to a car or to an airplane you are going to sell to someone right away, or a spam can. I thought we had beat this subject to death before.
Darryl

[Mark Julicher]

Re: Emron paint over Ceconite process?

AirTech uses Ceconite fabric, not Stits as mentioned above.

Airtech is legal with either fabric, or at least it was when I got my STC is 1999
In any event, urethane eventually cracks.

If I were looking at buying a urethane coated plane it would not be a show stopper. If I were recovering my plane again I would go with polytone.

[hangarb7]

Re: Emron paint over Ceconite process?

N44057 has Air Tech applied in 1989 and cracks along the length, mostly at the longerons, but other places, too. It popped off at the end of one of those false longerons and required a playing card size repair. Very brittle stuff, although blending and color matching was pretty easy and looks OK for the ol' gal.

Curious about the Monokote comment. Are you suggesting using just a liquid (dope material) or a clear fabric?

Thanks,

Jack Dernorsek
Rostraver Airport FWQ
Belle Vernon, PA

[N96337]

Re: Emron paint over Ceconite process?

I was going to just sit back and keep my mouth shut, but here's a few words from an ex-partial owner of a fabric/paint system... Paint is not just paint... Polyfiber's Aerothane is NOTHING like automotive polyurethane, AFS's pure polyurethane is NOTHING like automotive polyurethane, nor Aerothane. These two polyurethane paints have been formulated specifically to withstand the huge flex load that aircraft fabric has on it. They are two very different polyurethanes, but they are both the same in that they have the plastic fillers that make automotive paints so easy to spray as well as more "hiding" of flaws, removed. I have samples of both here in the shop.. aerothane that's more than 15 years old, and still flexible, and AFS that's a bit over 7 years old and it's still super flexible... ask acroeric... you can wad the stuff up in a little ball and it wont crack. Automotive polyurethane flex additives will (as stated above) evaporate, and you'll be left with a nice hard finish that will promptly crack, taking away the underlaying UV protection with it in most cases. Flex additives were brought forth when the flexible bumpers became popular on cars, and work well on them, as there is very little flexing happening, until it's damaged, where it's either replaced, or at the very least repainted...whereas your fabric aircraft is constantly flexing alot (in comparison) everytime it flies, or the engine runs.
It's an old wives tale that polyurethane can't be repaired... it can be done, and it can look just as good as any repair, with the proper techniques... it's just a bit more work, and takes more time than dope or polytone. I've done it. I know lots of other people that have done it with huge success.
The current STC's do specify the finish coats, and partly because of the cracking problem, but also because of the fire resistant specifications.
JH

[mhorowit]

Re: Emron paint over Ceconite process?

More than likely you can peel the Imron from the dope. I have never seen anyone apply it where I could not remove it. Peel it back to make the repair, and then refinish to match what was already done.
Mike

Jeeze I hope you're correct- Mike

[ROllerton]

Re: Emron paint over Ceconite process?

As a previous owner (sucker) of a imron over old dope over ceconite airplane I can tell you it just sucks. The dope continues to dry out, gets brittle, the imron holds the dope steady so it can delaminate from the fabric. I would never never never buy another airplane that had any combination of different paint systems.



Yes, you can repair and restick the dope back to the fabric, and you can peel back the paint and dope to do this, but its not practical to have these repairs not stick out and get attention from less than 20 feet away.

bob.

[flyguy]

Re: Emron paint over Ceconite process?

Well JH you have piqued my curiosity. I'm going to buy a small amount of Aerothane and play with it some. If anyone can make flexible paint I guess it would be Stits. Maybe I can use it to do some repairs.
Darryl

[VictorBravo]

Re: Emron paint over Ceconite process?

My first T-craft was DuPont Durethane over Ceconite. It was ringwormed and cracked all over. Clear Monokote would be an excellent repair over cracked urethane but would look pretty strange at the seams. I'd rather have Monokote over the bare steel frame than cracked fabric and car paint!

[N96337]

Re: Emron paint over Ceconite process?

Flyguy, you should give AFS a try too... it's interesting stuff to work with, and I've never seen anything so flexible! At least call Stewarts and talk to them about it!
I've never heard of the monocote, but that's pretty inventive!
When I bought my Tcraft in 1985, it had auto paint over ceconite..and LOTS of cracks and ringworm. I did what I could to sand and shoot silver into the cracks to try to prevent more deteration of the fabric, so my airplane became known all over the valley as "spot"... to make a long story shorter, it didn't do any real good...as soon as you'd get one crack somewhat sealed, another would form. A friend had his Bellanca Cruisemaster done the same way and it took a whole 2 years to start cracking... that was long before it was a requirement to follow through to topcoat with the proper product.
JH

[ROllerton]

Re: Emron paint over Ceconite process?

I found that If I worked dope Rejuivinator into the cracks and under the dope it would soften it enought to either let me remove a big patch of paint/dope from the silver layer, or stick it back down and soften the edges enough that i could work then down flat.

After it dried, I would take unthined dope and a small brush and strat filling in the cracks until they were level (or as level as I was willing to wait for).

I found out that they painted my plane with Cessna Hawaian Red (like the punch; AKA Resell Red) and I was able to get a couple of spray cans made at the PPG paint store with that enamel which I used to cover up my dope work.

Someone once suggested (I think it was the Randolph paint sales person at a flyin) that if they would have at least sprayed on rejuivanator per the specifications before putting on the enamel I would have had a better chance of keeping it stuck to gether.
There is nothing quite like pulling off some masking tape and having 4 or 5 feet of your dope/paint come off with it!

[Dano"T"]

Re: Emron paint over Ceconite process?

My plane was covered in 1981 with Ceconite 102 and finished in Aerothane. It does have some cracking, but most of it is on the belly wherever the fabric touches and vibrates against the tubing???? The only other spot is on the horizontal stabilizers along the seam. My plane is often outside during the winter...as I like to keep it at my lake home for some winter lake hopping....all in all I would have to say that under the circumstances it's held up rather well. It has also been on floats before and will be again. I hope to get quite a few more years out of it just as it is.....the tubing looks great still and I think with a little elbow grease I can remedy those small cracks in the dope on the belly.....heck, It could be worse...at least the cracks are where the sun don't shine...excuse the pun. I am going to try to repair the small cracks on the horiz stabs though for sure. As a side note: I typically wax it top to bottom twice each year...maybe it helps.

[taylorcraftbc65]

Re: Emron paint over Ceconite process?

JH has it right. My 1940 BC65 was done in Blue River process which became AFS. About the only thing that MEK does to the finish is do a REALLY good job of cleaning off the dirt, bugs, and oils. The paint on the plane is almost bulletproof. Brie

Flyguy, you should give AFS a try too... it's interesting stuff to work with, and I've never seen anything so flexible! At least call Stewarts and talk to them about it!
I've never heard of the monocote, but that's pretty inventive!
When I bought my Tcraft in 1985, it had auto paint over ceconite..and LOTS of cracks and ringworm. I did what I could to sand and shoot silver into the cracks to try to prevent more deteration of the fabric, so my airplane became known all over the valley as "spot"... to make a long story shorter, it didn't do any real good...as soon as you'd get one crack somewhat sealed, another would form. A friend had his Bellanca Cruisemaster done the same way and it took a whole 2 years to start cracking... that was long before it was a requirement to follow through to topcoat with the proper product.
JH