Silly Article on Fabric in Vintage Aviation

[flyingron]

Why on earth do we have an article on fabric punching in Vintage Aviation. Fabric punching is specifically disallowed by the FAA for finished dacron fabrics and Poly Fiber officially disparages it as well. Punching is a relic of the old cotton fabric days (and not even the die hard vintage guys are still using cotton fabric).

Sharp looking guy on page 37 though.

 

[J3 Driver]

Haven't gotten mine yet. I'll keep a look out.

 

[Jimmy cooper]

A recent article in vintage aviation describes how the pro DOES use a maul tester on ceconite, etc. if it registers 46 he passes it. Recently I sold a trophy winning t craft with a fresh annual. It was recovered with ceconite in 1996 and always hangared. The AI used a maul tester and when it read 50 he passed it. The other option is to cut out a piece of fabric and pull test it. Not on an airplane of mine! The maul test is commonly used on newer fabrics. I've owned a Stearman, two t crafts, a j3 , a champ. They were all ceconite. They were all tested this way.

 

[flyingron]

Well it may be commonly done, but it's unreliable and specifically disapproved by the FAA and the fabric manufacturers. Punch testing is for cotton and can only be used on the synthetic covering PRIOR to being finished. PolyFiber says do it based on fabric inspection. If the finish is intact, it's good. If the finish has deteriorated, the fabric is suspect.

 

[Tom-D]

A recent article in vintage aviation describes how the pro DOES use a maul tester on ceconite, etc. if it registers 46 he passes it. Recently I sold a trophy winning t craft with a fresh annual. It was recovered with ceconite in 1996 and always hangared. The AI used a maul tester and when it read 50 he passed it. The other option is to cut out a piece of fabric and pull test it. Not on an airplane of mine! The maul test is commonly used on newer fabrics. I've owned a Stearman, two t crafts, a j3 , a champ. They were all ceconite. They were all tested this way.

You should read the instructions for the Maule Tester, and show me where it says anything about Ceconite.

Any one that uses the Maule tester on ceconite is making their own rules as they go.

 

[Tom-D]

Well it may be commonly done, but it's unreliable and specifically disapproved by the FAA and the fabric manufacturers. Punch testing is for cotton and can only be used on the synthetic covering PRIOR to being finished. PolyFiber says do it based on fabric inspection. If the finish is intact, it's good. If the finish has deteriorated, the fabric is suspect.

 

[Tom-D]

Ceconite is a generic plastic, it never fails. the paint is the weak part of this system. when the paint becomes brittle it will crack, the test for that is simply poke your finger on the paint, if it cracks around your finger the paint has become brittle, and should be replaced.

Re-J ? maybe, that depends upon the type of paint. Rejuvenator, was invented for DOPE, it works on some paint too. URA types ? not so much.

 

[Capt. Geoffrey Thorpe]

The Stits manual discusses the use of a punch tester as a way to screen "suspect" poly fabric. I'd type out a quote, but the manual is at the hangar.

 

[Jimmy cooper]

Ceconite, for instance , is VERY susceptible to ultra violet and if the silver coat is not heavy enough can be damaged very quickly by sunlight. The maul test IS used on ceconite and other " modern" fabrics. If you think a pull test is commonly used, think again! The article in vintage , written by a very knowledgeable rebuilder , is the way it's done in reality. In no case is the paint being tested, it's the fabric that is in question.

 

[Tom-D]

Ceconite, for instance , is VERY susceptible to ultra violet and if the silver coat is not heavy enough can be damaged very quickly by sunlight.

I guess that is why Stewart's system, and Airtech doesn't use it.

The maul test IS used on ceconite and other " modern" fabrics. If you think a pull test is commonly used, think again! The article in vintage , written by a very knowledgeable rebuilder , is the way it's done in reality. In no case is the paint being tested, it's the fabric that is in question.

How many of these systems have you completed?

I have been doing recovery for a very long time, starting way back in the cotton/dope era and I have yet to see the maule tester give an accurate reading of fabric strength on ceconite.

The paint is always the first to fail, most often indicated by the ring cracking caused by pressure being applied to the surface of the paint. or cracks along hard point areas.

The paint on my Fairchild 24 was damaged to the point it was peeling off in newspaper sized sheets and the bare ceconite was as strong as the day it was put in service.

 

[Greg Bockelman]

I guess that is why Stewart's system, and Airtech doesn't use it.

What do they use? I was under the impression that the fabric was all the same, the finish is what was different.

 

[Jimmy cooper]

Your description of the paint peeling off your Fairchild in large strips should tell you a lot about how it was prepared for painting. Someone screwed up big time. Another big mistake some years back was spraying Imron on any kind of fabric aircraft. Most had to be recovered. The fellow who wrote the article for vintage would be a good contact. He has many years experience and an excellent reputation in rebuilding older fabric aircraft. It doesn't really matter how long you've been doing it but rather if you do it right. Right?

 

[Tom-D]

What do they use? I was under the impression that the fabric was all the same, the finish is what was different.

Poly Fiber uses a primer called poly brush to penetrate the weave, then silver umpteen coats. (air dried) it's the pink or blue you see by looking inside of the fabric.

Airtech uses a URA 3 coat primer filler with a UV filter added cured with a catalyst.

Stewert's uses a laytex "Ecofil" with a UV filter added. (air dried)

All have their own top coat paint.

Ceconite is a trade name, for a FAA approved aircraft fabric all systems use it, there 5 looms manufacturing it, each of the three major systems have their stamp placed on the fabric, it is a STC requirement.

 

[Tom-D]

Your description of the paint peeling off your Fairchild in large strips should tell you a lot about how it was prepared for painting. Someone screwed up big time. Another big mistake some years back was spraying Imron on any kind of fabric aircraft. Most had to be recovered. The fellow who wrote the article for vintage would be a good contact. He has many years experience and an excellent reputation in rebuilding older fabric aircraft. It doesn't really matter how long you've been doing it but rather if you do it right. Right?

My Fairchild was restored by the for most restoration shop on the west coast, in Santa Paula Ca. I doubt it was done wrong.

And the best resource for any information on fabric recovering is the STC holder of which all are available on line for advice and guidance.

There are a lot of experts in this field, all with their own opinions on what is the best method of repairs and testing.

The FAA has yet to approve a standard method of testing ceconite simply because it has been proven time and time again that it will be removed from service long before it fails.

 

[Greg Bockelman]

Poly Fiber uses a primer called poly brush to penetrate the weave, then silver umpteen coats. (air dried) it's the pink or blue you see by looking inside of the fabric.

Airtech uses a URA 3 coat primer filler with a UV filter added cured with a catalyst.

Stewert's uses a laytex "Ecofil" with a UV filter added. (air dried)

All have their own top coat paint.

Ceconite is a trade name, for a FAA approved aircraft fabric all systems use it, there 5 looms manufacturing it, each of the three major systems have their stamp placed on the fabric, it is a STC requirement.

Ok. I got the impression from what you wrote in Post #10 that the fabric was something totally different, when in fact it is basically the same, just the process is different.

 

[Tom-D]

Ok. I got the impression from what you wrote in Post #10 that the fabric was something totally different, when in fact it is basically the same, just the process is different.

Nope ceconite is still ceconite, it is in the family of Dupont chemicals of Teflon, Dacron, and several other "LON" chemicals. nothing really chemically adheres to it. The Paint must be forced thru the weave by brushing or any method the STC holder has elected to use. Airtech is the only STC that is sprayed on the first coat because it will wet out the fabric without forcing the paint thru the fabric.

 

[flyingron]

Absolutely. Steve Wittman learned the hard way to use the appropriate materials for the fabric being used. You can't use dope to stick the fabric down as it can't wet the weave.

As for paint, the processes typically use a UV base layer that as Tom-D says has to be brushed into the weave. Of course, once you lay that down, you've got some more flexibility with applying the top coats.