Toxic nature of covering systems?

[Soarmaster]

I am considering a kit project, and most of them are using one of the "glued, ironed, doped' type systems for their covering. I'm looking at some of the manuals for these systems and am a bit put-off by the apparently toxic nature of the chemicals involved. The precautions advised by the manuals are alarming. I'm not sure I want to put a new toxin-load on this 65 year-old body.

For those of you with actual experience working with this systems,
Two questions:

Are these chemicals as toxic as the manuals make them appear?

Which system is supplied with the Airdrome kit for the Dream Classic?


Thanks in advance for any feedback.

[DaleB]

Old school fabric dope smells absolutely wonderful, and brings back memories of a happy childhood.

That said, it's also possibly why I have this uncontrolled twitch and can't remember whether I had breakfast this morning. :) Not really, but you get the idea. There's a lot of very strong solvent vapors, so a lot of ventilation is a good idea. Another good idea is using Stewart Systems water-borne materials instead. Your wife and neighbors will thank you, unless they really enjoy getting a little high now and again.

[Dana]

Old school butyrate dope / Ceconite: as Dale said, some of us love the smell. Toluene solvent, not really good for you but probably not the worst.

Polyfiber (Stits): Smells nasty, MEK solvent. Dunno if it's worse than toluene but it just smells toxic. Requires fewer coats than dope.

Stewart: waterborne, little smell, requires different techniques.

Some people use acrylic latex house paint.

Oratex: requires no paint at all, color is in the fabric, fast, lightweight, expensive.

I don't know about the Dream Classic, but most kits don't include the finishing materials, you can use whatever you want.

[FlyingRon]

Note that even with Ceconite you can't start with butyrate dope but Rand-O-Proof or the like (much as using PolyTak/PolyBrush). Read and follow the manufacturer's requirements for at least the first couple of steps in the process. Steve Wittman learned this the hard way. Stewart is indeed less noxious.

All three of these have very nice instructional manuals that you should read.

And if you think the made-for-aircraft dopes are potentially dangerous, you should really stay away from some of the polyurethanes that some are using for top coats. The problem with them is they DON'T smell bad enough and you're tempted to breathe toxic amounts rather than using the proper respirator.

[Sam Buchanan]

I am considering a kit project, and most of them are using one of the "glued, ironed, doped' type systems for their covering. I'm looking at some of the manuals for these systems and am a bit put-off by the apparently toxic nature of the chemicals involved. The precautions advised by the manuals are alarming. I'm not sure I want to put a new toxin-load on this 65 year-old body.

For those of you with actual experience working with this systems,
Two questions:

Are these chemicals as toxic as the manuals make them appear?

Which system is supplied with the Airdrome kit for the Dream Classic?


Thanks in advance for any feedback.

You still haven't called Robert Baslee at Airdrome yet, have you. ;)

When you do, Robert can explain how to finish his kit with non-toxic materials. Have your other questions ready as well.

[PNelson]

I'm not sure I want to put a new toxin-load on this 65 year-old body.

For those of you with actual experience working with this systems,
Two questions:

Are these chemicals as toxic as the manuals make them appear?

Yes, the chemicals used for Stits Poly are highly toxic, but if you use the proper breathing mask or a forced air respirator it can be very safe. For any urethane product you also want to protect you skin and eyes by wearing a body suit and eye goggles.

There are several Airdrome planes that have been successfully covered with Latex house paint. I think if you search this site and others you can find plenty of info about this.

[Sam Buchanan]

Here are details on using acrylic (latex) paint for finishing my Airdrome Aeroplanes D.VII:

http://fokkerd7.com/paint-1.html (http://home.hiwaay.net/~sbuc/fokkerd7/paint-1.html)

8125

Latex paint has been a common finish material for ultralight and light experimental aircraft for nearly thirty years. I have found it to be flexible, durable, and easily applied without spray equipment or respirators. The cost is a tiny fraction of "certified" materials (Polyfiber).

[rwanttaja]

One of our Fly Baby crew painted his plane with latex, and is very pleased with the results, even after ten years.

http://www.bowersflybaby.com/tech/drew_paint.html

http://www.bowersflybaby.com/pix/drew2.jpg

However, it does still require that the fabric be attached using the conventional products.

Ron Wanttaja

[Soarmaster]

Here are details on using acrylic (latex) paint for finishing my Airdrome Aeroplanes D.VII:

http://fokkerd7.com/paint-1.html (http://home.hiwaay.net/~sbuc/fokkerd7/paint-1.html)

8125

Latex paint has been a common finish material for ultralight and light experimental aircraft for nearly thirty years. I have found it to be flexible, durable, and easily applied without spray equipment or respirators. The cost is a tiny fraction of "certified" materials (Polyfiber).


Thanks for the information Sam! I'm looking at the Stewart Systems website -- and I am suspecting that all these systems (ceconite, poly-fiber, and Stewart) are using the exact same 3 weights of polyester weave fabrics. There could be some way the fabric might be factory-prepped to favor their specific products, but I doubt it. Did you feel the need to use Stewart fabric in order to use their glue?

I have ordered the Poly-fiber practice kit in order to experience their chemicals on a small scale. I'm thinking of ordering a small amount of Eko-bond and doing an equivalent test of the system you have used on your D-VII, but using some of the fabric from this kit. Do you think the poly-fabric will be an issue?

Bob (soarmaster)

[Dana]

They all use the same fabric.

Instead of Eko-bond, get some 3M Fastbond 30NF, which is the same thing, or close, but cheaper.

[Sam Buchanan]

The source of the fabric is a non-issue other than price. Unfortunately, it seems the inexpensive uncertificated 1.8 and 2.7 fabrics we used to get from Aircraft Spruce are no longer available. This leaves you with one of the uncertificated light fabrics from a major vendor such as Polyfiber:

https://www.aircraftspruce.com/pages/cs/fabric/polyfiberuncertified.php

You can do tests if you wish but this is a proven method with nearly 30 years of field history. :)

[DaleB]

I took the fabric covering workshop at Oshkosh a few years ago. That was really informative, and gave me a chance to work with some of the solvent based products... I think it was the Polyfiber stuff. When (OK, if) I ever get to the point of covering my current project, I'll use the 3M Fastbond and either Stewart products or house paint to do it. I also have the Polyfiber practice kit sitting down in my basement, unused... I don't know that I'll ever use it, but no one around here is interested in it.

[FlyingRon]

The Stewart stuff is tested on Ceconite and Superlite stuff. Should work with other Dacrons as well. Your top coats aren't so important (you can use latex or Imron or Krylon for all I care), but you need to make sure you provide right stuff at the lowest level to make sure that things are adhered and properly protected.

[Sam Buchanan]

I've had a couple of opportunities to remove uncertified fabric that was bonded to an airframe with Stewart's adhesive. I no longer have any concerns about bond strengths...the glue was stronger than the fabric in most areas. The most important factor is using the proper technique for applying the water-borne adhesive, it is a different technique than applying Polyfiber's product. But once learned I find it easier to work with than Polytac.....and no deadly fumes!

[Soarmaster]

The source of the fabric is a non-issue other than price. Unfortunately, it seems the inexpensive uncertificated 1.8 and 2.7 fabrics we used to get from Aircraft Spruce are no longer available. This leaves you with one of the uncertificated light fabrics from a major vendor such as Polyfiber:

https://www.aircraftspruce.com/pages/cs/fabric/polyfiberuncertified.php

You can do tests if you wish but this is a proven method with nearly 30 years of field history. :)


I don't doubt that it works, but I want to see it and experience working with it before pulling the trigger on ordering a kit. I'm 65, retired, and living on a social security check. So this project is a huge financial risk. I even have to put up a new building for this, if I do it. The process of obtaining a building permit is just beginning with my Village Council ( I live in an Eco-village in very rural Missouri), and there's no love lost for metallic buildings here. If I'm denied the permit.... no building = no project. So I'm just being super-cautious about the whole thing.

By the way, I am a retired Sailmaker (like for sailboats and the 'sewn products industry' ) So to me, with my background, the fabric prices seem perfectly reasonable. Even very plain 4 ounce darcron , like you'd see on a typ. sewn-sail ultralight, would cost as much or more per running yard, and it's only 45 inches wide.

Bob

[Soarmaster]

Here are details on using acrylic (latex) paint for finishing my Airdrome Aeroplanes D.VII:



Sam,

Did you use the Stewart's wash and etch products to prep the raw alum. that airdrome uses for the ekobond adhesive? Or do you have an alternative prep? I'm watching the Stewart videos and am not too fond of the acid etch idea.

[Sam Buchanan]

Sam,

Did you use the Stewart's wash and etch products to prep the raw alum. that airdrome uses for the ekobond adhesive? Or do you have an alternative prep? I'm watching the Stewart videos and am not too fond of the acid etch idea.

Just wiped it with acetone to remove grease. Adhesion to the aluminum is primarily for holding the first piece of fabric in place until the second piece is overlaid and glued to it, then taped. The strength of the covering comes from fabric-to-fabric bonds.

[planecrazzzy]

I'm 65, retired, and living on a social security check. So this project is a huge financial risk...

Only two things you need to fly

AIRSPEED & MONEY
.
Gotta Fly...

Stitts is my choice because it will EXTINGUISH it's self when removed from the source ...fireproof

Others will burn .
.

[Soarmaster]

Just wiped it with acetone to remove grease. Adhesion to the aluminum is primarily for holding the first piece of fabric in place until the second piece is overlaid and glued to it, then taped. The strength of the covering comes from fabric-to-fabric bonds.


Thanks, that's a relief. I can handle an acetone wipe-down, and yes, I'm beginning to get from the various system manuals that it's the fabric to fabric bond that's really important. This makes sense -- In a sewn-sail ultralight, the fabric isn't bonded to the frame anywhere! An occasional grommet and screw to keep the sail from sliding off the end of a tube maybe, but other than that it isn't attached at all. Ditto for hang gliders.

[Sam Buchanan]

Coleman lantern fuel is also a good pre-glue agent, like acetone it flashes off without leaving a residue.

[Dana]

Coleman fuel is VMP naptha. (VMP = "varnish makers & painters").

[FlyingRon]

Yep, just a light petroleum solvent. Naptha, mineral spirits, varsol, stoddard, etc... are all in the same family.

[Jeff Point]

Sam,

Did you use the Stewart's wash and etch products to prep the raw alum. that airdrome uses for the ekobond adhesive? Or do you have an alternative prep? I'm watching the Stewart videos and am not too fond of the acid etch idea.
I'm not Sam but I'll chime in. The acid etch process is for aluminum that is going to be painted and is done prior (immediately prior) to priming. It isn't needed for aluminum that is covered by fabric.