- This topic has 9 replies, 6 voices, and was last updated 14 years, 11 months ago by
.
-
Posts
-
I would appreciate any input on the shrinking and resultant torsional rigidity of 1/2 ounce nylon. Does anyone have any experience or advice to share?
Wow! That is old school. Its possible to crush some structures with it.
I wouldn’t advise using it. There are other easier coverings available.
This from a Luddite.First of all, where do you purchase 1/2 ounce? I have only been able to find 3/4 ounce.
It has good rigidity, and you need to make sure that it is the heat shrink type. You should put on 2 coats of dope to seal it. I have put F1As in trees with this, and only came out with a few dents that came out quickly with the iron afterwards.
You do need to have a decent structure, better than a Luddite structure.
I purchased this batch from Hang-em High Kite Store. It is indeed 1/2 oz/sq-yd polyester coated rip-stop nylon.
I put all the heat to it my heat gun would deliver, which is enough to crunch other structures and/or melt polyspan (which is my real covering of choice). I was hoping the r-s nylon would, as expected, give a stiffer structure with more “split resistance on Larger structure. I have just put on a coat of 60/40 butyrate and will be interested to see if it caused any additional taughtening.
There are two types of rip-stop nylon material. One shrinks with heat, the other does not. Did you get the type recommended for RC models?
I have not tried this on power models yet, and wonder if the exhaust oils will saturate it? Am thinking about putting plastic over the rip-stop to seal it in high exhaust areas.
Any other experience with this on power models?
According to the folks at Hang-em High this is what the r/c guys use.
I plan to use sprayed on clear Klass Kote epoxy for fuel proofing as I do on polyspan.
Generic half ounce spinnaker fabric was and still is, available in both polyester and nylon weaves with varying finishes depending on specific application. Be aware that the nomenclature “1/2 oz.” and “3/4 oz.” are nominal weights and have nothing to do with actual finished weight. Most fabrics in small quantities (read that , retail) will be available in a wide range of colors from any professional sail loft, either in stock or on special order. Some of the finishes may give zero porosity without any additional sealing , others may reject application of liquid finishing materials for sealant. If you can find a roll end remnant in a loft that has been in business for some time, there was a super light laminate of 1/4 or 1/2 mil mylar with a polyester scrim that would make an outstanding medium weght covering material. Last time I asked my contact at one of the suppliers for it I was told they didn’t have any in stock but would make a run if I could commit for a 5000 yard minimum order.
Cheers!, Pete (former sail loft owner)I concurr with what Pete wrote and while not a sailmaker I was involved with kite manufacturing for 10 years and handle a lot of cloth brands.
The cloth most suited as a covering material is polyester Icarex P31 which everybody says is “1/2 oz” cloth; it ain’t, it’s 31 grams per sq metre or 0.7 oz per sq yard. From memory the so called “1/2” and “3/4 oz” cloth is the uncoated weight of the fabric as woven so like Pete said.. beware 😉Ployd in OZ
Ployd
Yep, that’s exacly right.
The nominal weight of the cloth is the nominal (design) weight of the “greige goods”, that is before finishing.
Oh yeah, if I remember from long, long ago, a sailcloth yard is only 28 or 28 1/2 inches wide which goes back to the days of cotton and linen sailcloth. Thus 0.7 oz./yd with finish is pretty close to 0.5 oz./ yd. for 28″ wide cloth (unfinished).
And that’s probably a whole lot more than most of you were interested in knowing.
Cheers!Rip Stock (which was previously known as Icarex) is great stuff….But, it does not give the structure any rigidity, no matter how tight you try to shrink it. we have used it on our F1C and F1J models for the last 7 years and the stuff is pretty bullet proof as far as rips. We use Stik-It to bond it down. I set the iron (Mono-cote) to a mid setting and shrink it somewhat. Then I crank it up and get rid of the various small wrinkles that show up.
Again, it adds nothing to the structural strength, jyst great covering. Some folks will put a few light coats of dope on the middle (about 6″ from the center section) for fuel proofing. I have also run it without, but after a while it does soak up a bit of oil…
- You must be logged in to reply to this topic.