differences in Dacron

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Pops

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Like TFF the last un- certified fabric I used had a small blemish about every 15-20' and if under the pinking tape at a rib it would never be seen. Its really very small and hard to find.
 

rv7charlie

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Just a caution about mixing and matching chemicals and fabrics from different sources. The great Steve Wittmann died when fabric pealed off the wing of his custom Tailwind.
My memory of the accident account was that it wasn't mixing chemicals/fabrics; it was mixing *processes*. My memory is that the older brand of fabric he was used to working with was a much courser weave, and the process was to simply clamp the fabric on the structure and apply the glue on the fabric, and the glue penetrated through to the structure. Again, my memory is that he used his familiar process, but the new-to-him brand of fabric was a much tighter weave, and the instructions for it said to pre-coat the structure with glue before applying the fabric, then another brush of glue on top, so that the fabric was fully encapsulated. With only the top application of glue, there was inadequate penetration, and therefore inadequate bonding to structure.

If someone has a better memory of the events, please correct me.
 

rv7charlie

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Uncertified means it was rejected for that purpose. May be blemished but doesn't necessarily mean it's bad.
Does it mean it was *rejected for that purpose*, or does it mean what it says; 'uncertified'? ex: There are companies with certified EFIS products, and identical 'uncertified' (experimental) EFIS products that are exactly the same product, minus the paperwork.
 

challenger_II

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Very close to the mark.
Steve was accustomed to Grade A Cotton. One uses nitrate as an adhesive for gluing fabric to fabric. Steve continued this method after he started using polyester fabric. It took a while, but the practice caught up to him. Was shortly after the accident investigation became public that the principals behind the Ceconite process issued a service bulletin regarding the use of the correct adhesives for their covering process.

My memory of the accident account was that it wasn't mixing chemicals/fabrics; it was mixing *processes*. My memory is that the older brand of fabric he was used to working with was a much courser weave, and the process was to simply clamp the fabric on the structure and apply the glue on the fabric, and the glue penetrated through to the structure. Again, my memory is that he used his familiar process, but the new-to-him brand of fabric was a much tighter weave, and the instructions for it said to pre-coat the structure with glue before applying the fabric, then another brush of glue on top, so that the fabric was fully encapsulated. With only the top application of glue, there was inadequate penetration, and therefore inadequate bonding to structure.

If someone has a better memory of the events, please correct me.
 

Turd Ferguson

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Does it mean it was *rejected for that purpose*, or does it mean what it says; 'uncertified'? ex: There are companies with certified EFIS products, and identical 'uncertified' (experimental) EFIS products that are exactly the same product, minus the paperwork.
It means a defect prevented it from receiving the ink stamp marking.
 

karmarepair

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You're absolutely sure about that? There's no chance whatsoever that generic 'unsized' polyester fabric (like you could buy at a fabric store) could be sold as 'uncertified'?
Sizing and heat shrinking are two different things. Quilter and sewist here - un-shrunk polyester is as rare in the sewing/quilting/fashion marketplace as to be effectively unobtainable. This was NOT always so - there was a time when suit lining was un-shrunk, as it gave a softer "hand". That was Then, Now, no one wants their suit to get all deformed if the cleaner presses it, so even cheap suit lining is heat shrunk before it is sold.
 

challenger_II

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Butteryfly brand polyester dress lining is still omni-directional shrinkable but is WAY too light for a man-carrying flying machine. HOWEVER, it works great on One's larger model airplanes for a dope and fabric finish. :)
 
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