Fabric needs

[Kurt.A]

Hi Guy's,
Looking for a rough idea how many sqft of fabric is on a Mod II?

[Kurt.A]

According to my new Poly Fiber manual the answer is 500 sqft for a Kitfox or Avid.
Did some interesting math. A 12"X12" sample of my current covering weighs 1.37 oz's. which works out to 40.78 lbs for fabric and paint. Poly fiber Med weight with UV coatings and Poly Tone top coat as per the book should come out at 29.4 lbs. Poly Fiber light weight with UV coatings and Poly Tone top coat would come in at 22.57 lbs. Oratex 600 with coatings comes in at 10.9 lbs and Oratex 6000 with coatings comes in at 15.6 lbs.

[avidflyer]

I tried to answer you yesterday, but my PC wouldn't let me, so I'll try again. I've covered an Avid and a Kitfox, and would say to figure about 35 yards. Realize that you still have quite a bit of waste, fabric is 70" and you only use about 50" to cover the wing for instance. If you found where Polyfibre said their weight is so much per ft, and you figure a yard as being 36" X 70" to arrive at your weight, you will end up with a way higher figure that way then what you will actually put on the plane. Poly fiber's sample figures to cover a J3 Cub are quite high in my opinion. I used about 3 gallons each of poly brush, poly spray, and poly tone, plus thinner. When you shined a light inside the fabric it didn't show through after the poly spray was put on. Must have been thick enough. YMMV, but that's my story and I'm sticking to it. :-) Jim Chuk

[Kurt.A]

Jim,
Of the 35 linear yards of 70" fabric how much would you estimate as being waste? The Poly fiber manual is very specific with regards to the amount of fabric on a cub when it left the factory, 731 sqft. Their estimate for selecting materials to recover a cub is 45 linear yd's. 45 linear yards computes to 787.5 sqft. allowing for waste of 56.5 sqft. They are not specific in the manual as to how much is actually on a kit fox when complete but give a generalization of 500 sqft for most experimental aircraft. They estimate fabric to purchase for a Kitfox or Avid as 38 linear yards. Just trying to get a very close idea how much weight the finished fabric job will add using the different methods available. I am really leaning towards the Oratex fabric. Super light and no toxic fumes to deal with.

[jrevens]

Kurt,
I did a layout on graph paper and determined that 82' (25 m) of fabric that is 75 or 76" wide will do a Series 7SS. That is one of the minor advantages of the Oratex - you can probably get it in that width (as opposed to 72") if you ask. I did. That's a pretty accurate, not much waste calculation. There is still quite a bit of trimmed-off waste of course, and a few decent sized pieces left over - possibly enough to do the rudder or vertical fin again. It's an educated guess, but I'd say 450 to 500 sq. ft. on a Series 7.
I've pre-cut out all the pieces from the roll & can confirm that it is enough. As an update on my covering, my tail feathers are complete & I'm starting on the wings. I've had a lot of family things in the way lately... it's pretty slow goin' when you can only work on something about 1 hour every 3 weeks.

[avidflyer]

Kurt, if you are trying to figure out the finished weight by using the sq. footage of fabric used, I would go measure the different surfaces of the plane and calculate it from there. Length times width, and estimate on the rounded surfaces. That should get you pretty close. When I said in an earlier post that Poly fiber is high on their estimate of materials for a recover on a Cub, I was thinking about the chemicals especially. Just looked in my manual and for instance they say 1 gallon of poly-tak. I don't think I used more than a full quart on either of my planes that I covered. And that includes glueing the fabric down on all the 1" wide cap strips top and bottom in the wing. There has to be a lot more glue used in an Avid or Kitfox wing than a cub. Jim Chuk

PS, I'm now curious on the sq. footage on the plane myself. If I get time, I'll figure it out myself.

PS PS went and did some measuring and came up with about 375 sq. ft. of painted fabric surface. 35 yds. that is 70" wide = 612.5 sq ft.

[Kurt.A]

Thanks for the reply's guy's
Have you guy's done any test patches to see if the manufacture's published weights are correct?
John have you needed to or tried Oratex's tech assist? Just curious if they are as helpful as they claim if needed. Are you using 600 or 6000?

[jrevens]

Thanks for the reply's guy's
Have you guy's done any test patches to see if the manufacture's published weights are correct?
John have you needed to or tried Oratex's tech assist? Just curious if they are as helpful as they claim if needed. Are you using 600 or 6000?

There was a recent discussion about comparative weights in the "Oratex revisited" thread. The only real thing that I can add to that is that weight of painted fabric finishes can vary quite a bit. Even PolyFiber's published information and data is contradictory about weights. That is not true of Oratex. The Oratex weight seems to be accurate & fixed, & is always going to be lighter than a conventional painted fabric job if comparing (for instance) the 6000 to medium weight PolyFiber ... the question is how much, which is understandable with the wide variance in paint types, application techniques, number of coats, etc. It is also demonstrably stronger.
I'm using the 6000 material. The customer support has been outstanding. Lars (of Better Aircraft Fabric) in Alaska, has been extremely available at all hours for telephone & email help. I think my friend Gary, here in the Denver area, can also attest to that.

[Kurt.A]

John,
In some of the pics that I have seen the oratex fabric appears to be opaque/ translucent, not sure if they are pics of 600 or 6000. Is this true for the 6000 on your project?

[jrevens]

Yes, it is slightly translucent and you can make out the structure that it is contacting with strong back-light. The main reason that it is lighter I believe is because the finish "paint" is no thicker than it needs to be. The 6000 is probably a little more opaque than the 600 - I don't know for sure.