Day One: Fabric Workshop; some questions

[mhorowit]

Finished day one of the workshop. More tomorrow.
Jim and Dondi Miller.
20 folks attending.
Covered an aileron
Learned to rib stitch.
Although he didn't come out and say it, Jim wasn't wildly enthusiastic about the AFS system.

Met and sat with Dan Brown of this forum; a distinguish looking gentleman.
He has a confirmed Tom Young sighting which is good for folks looking for a Tcraft instructor.

He was constantly checking his clothes iron temp with an IR thermometer. Is that constant testing necessary?

When he was describing metal prep he mentioned using Tube Seal or boiled linseed oil, but he seemed to be saying pour it in the tubing and leave it in. I thought we drained the stuff out. Anyone?

More on metal prep: remove rust, then seal with Krylon lacquer spray as a barrier. 2-part right over it with no need to clean it off

Avoid self etching primers as the etching continues working long afterwards. Anyone?

No top coat needed with 2 part primer.

Can use any 2 part primer (I thought the STC began at bare metal) as long as it's not affected by MEK

I couldn't see how they were going to teach 20 people how to do the modified seine knot, but I learned it in about :15.

Sears makes a good respirator; only need a respirator if you're spraying something. MEK is ok in well ventilated area

Day one was very satisfying; tomorrow we'll continue with our friend the aileron. - MikeH

[flybikefarm]

Re: Day One: Fabric Workshop; some questions

Ask Dondi how she likes her margarita. Thats my cub in there display. George

[flyguy]

Re: Day One: Fabric Workshop; some questions

Mike my first BC12 had epoxy/2 part (glossy white!) paint on the tubing and it appeared to be totally bullet proof. If I was determined to do a frame the best I could from the ground up that is the way I would go.

You definitely want to invest in a respirator. I use one even if I am just opening a can of anything that has the nasty stuff (MEK, acetone, ect.) in it.

That stuff will screw up your body in ways that they don't even have names for.

I am still wondering if anyone is ever going to use/certify/test, on aircraft tubing, the rust conversion uncoating that converts the remaining pits and light rust to a black, seemingly inert material. From my experience I sure would trust it more than lacquer and I don't have anything against lacquer as I just finished painting my Camaro with it.

I don't like the idea of putting lacquer under the epoxy though, seems like a weak link to me, but maybe they have a good reason.

Isn't learning to make a good ribstitch with a hidden knot a real hoot.

DC

[Ray36048]

Re: Day One: Fabric Workshop; some questions

Yes, checking the temperature is important. Every square inch of the fabric must be heated to 350 for final shrink.

The tube seal is great stuff. You put it in and leave it there. You need to seal the hole with a special rivet. It wiil also show any pin holes.

Use the 2 part epoxy over the bare steel very soon after blasting. Do not use anything under it other than a self etching primer. Interesting, Polyfiber was selling a self etch primer for years, they seem to have discontinued it. In the old manual they said it was the only process that would servive for 6 mos under water.

Piper used a self etch primers for years on all of the Cherokees. It stops etching soon after being applied, if you ever stripped a Cherokee, you will know it is great stuff, very tough to remove.

2 part epoxy does not reach full chemical resistance for at least 72 hours at 70 degrees. I would not put any fabric cement on it for at least a week.

I would always use the same brand epoxy as the fabric process. These people have done all of the testing for the STC. The last thing you need is for the primer to fail under the fabric.

Buy a fresh air supply respirator.

[mhorowit]

Re: Day One: Fabric Workshop; some questions

Ask Dondi how she likes her margarita. Thats my cub in there display. George

Passed along your hello - she has a remarkable memory - MikeH

[mhorowit]

Re: Day One: Fabric Workshop; some questions

Isn't learning to make a good ribstitch with a hidden knot a real hoot.

DC

Yeah, then he showed a shortcut. Felt really happy about learning that knot.
Hope it's like muscle memory, cause I won't be using it for a while - MikeH

[N96337]

Re: Day One: Fabric Workshop; some questions

Mike,
What doesn't he like about the AFS system? Has he ever used it?
JH

[mhorowit]

Re: Day One: Fabric Workshop; some questions

Mike,
What doesn't he like about the AFS system? Has he ever used it?
JH

He kept mentioning the "Blue River System" and that AFS was unable to tell him how the new system differed from the old - MikeH

[N96337]

Re: Day One: Fabric Workshop; some questions

Hmmmmmm.....sounds like sour grapes on his part... it's easy to tell from the "blue river" system...different glue, different topcoat, different fabric (from the early), different deal entirely...but he's a Polyfiber salesman...what else would he say? I've used both... like some things about each, and love them both.
JH

[Ragwing nut]

Re: Day One: Fabric Workshop; some questions

He was constantly checking his clothes iron temp with an IR thermometer. Is that constant testing necessary?

When he was describing metal prep he mentioned using Tube Seal or boiled linseed oil, but he seemed to be saying pour it in the tubing and leave it in. I thought we drained the stuff out. Anyone?

More on metal prep: remove rust, then seal with Krylon lacquer spray as a barrier. 2-part right over it with no need to clean it off

Avoid self etching primers as the etching continues working long afterwards. Anyone?

No top coat needed with 2 part primer.

Can use any 2 part primer (I thought the STC began at bare metal) as long as it's not affected by MEK

MikeH

If you have a GOOD iron, the temp should not flucuate that much Once you set it, it should be good to go unless he was checking each time he changed the temp, then yes, continual check is required.

Tube seal should be poured in to completely fill the tube, then drain the excess out. It is a shellac type coating that will harden.

Do not put laquer under epoxy, it will weaken the mechanical attachment of the epoxy.

Etching chemically treat the surface of the steel and give it teeth to better adhere the topcoat and stops oxidation just as alodine does for aluminum. Etch primers are not required with all epoxy primers but are good step. If I have to make repairs after blasting I will etch prime to stop oxidation or if I am ready to spray epoxy I shoot Stits epoxy over bare metal, excellent stuff and pricey. I don't use anything else.

Correct, no need to top coat with 2 part epoxy primer

Depending on what covering system you are using will depend on what you can and can't do. John Goldbaum (Stits and Ceconite) got tired of warrantying people's mxing and matching so the last time revised the manuals he made the STC go from primer to finish color, no exceptions anymore. It use to only cover up through silver.

I have a hard time not using anything but Stits epoxy on all tubing no matter what covering system I use. Excellent stuff with good coverage and impervium.

Mike

[jgerard]

Re: Day One: Fabric Workshop; some questions

I still like to top coat over 2-part epoxy, even Stits epoxy.

I am finishing up a set of BC12D wings with the AFS (now Stewart's System) and everyone that stops by the shop is amazed at how nice it is to work with. I sure like how easy it is to nail the tapes down and not have to worry out the pinks popping up on me.

[Pearson]

Re: Day One: Fabric Workshop; some questions

Any suggestions on the best way to refinish a sheet of aluminum I am putting over my wing tanks? It is Alclad. Would you still use alodine, even though it has a coating of nickel? Do you scuff it with a Scotch Brite pad, or just squirt some self etching primer on it and topcoat it?

[mhorowit]

Re: Day One: Fabric Workshop; some questions

Depending on what covering system you are using will depend on what you can and can't do. John Goldbaum (Stits and Ceconite) got tired of warrantying people's mxing and matching so the last time revised the manuals he made the STC go from primer to finish color, no exceptions anymore. It use to only cover up through silver.

Mike

Did he get tired or did the feds recognize that non-flexible final coatings were cracking, leading to UV exposure for the fabric? I was under the impression the fed had to step in.

On the primer, we may be saying the same thing, but I specifically asked and he said 'any 2 part not affected by MEK'.

Interesting and frightening on what I'm hearing back from the forum vice what Jim/Dondi say, esp. the contrasting view that the use of Krylon lacquer spray as a preservative, without removing it, would impare the epoxy's ability to hold. - MikeH

[N96337]

Re: Day One: Fabric Workshop; some questions

Actually that order to change up through topcoat did come from ACO in LA. I was involved with AFS at that time and it wasn't Jon or any of the other principals, although we were all getting tired of people trying to throw Imron or something else over fabric, and then crying when it cracked.
Ragwing is dead on whith what he's saying about the Krylon.... ANY paint or primer that you apply is only as good as what's under it!! Krylon (and especially laquer!!) would be only a little better than throwing dust on the substrate before putting good epoxy primer on, in my opinion.
I like to topcoat epoxy too Jason. I've had it explained that even epoxy isn't meant to be a permanent topcoat...it's still a bit porous. That came from more than one paint formula chemist, so I take it pretty much as gospel! Dried topcoat doesn't weigh much, and with the life of the modern coverings, I want to do all that I can to protect the substrate.
JH

[Ragwing nut]

Re: Day One: Fabric Workshop; some questions

Any suggestions on the best way to refinish a sheet of aluminum I am putting over my wing tanks? It is Alclad. Would you still use alodine, even though it has a coating of nickel? Do you scuff it with a Scotch Brite pad, or just squirt some self etching primer on it and topcoat it?

It does not have a coting of nickel. Alclad has a coating of pure aluminum to prevent corrosion. I would alodine and prime to insure proper adhesion of your topcoat.

Mike