What weight of fiberglass cloth do you use?
06-13-2013, 11:14 AM
#1
What weight of fiberglass cloth do you use?
I am in the process of rounding up the materials to fiberglass a kit built Top Flite Cessna 182. This is my first time covering with fiberglass I normally use Oracote or Monokote and years ago I used Silkspan and dope. Having found all these lovely how to videos and articles this time I thought I should give fiberglass a try. I plan on using a water-base finishing resin I have already purchased. My wife can't stand epoxy fumes in the house and I prefer not to cover in a garage braking 90 degrees. Now comes the question of what weight of fiberglass cloth? I have seen 1/2 oz. and .20 oz cloth which would provide the smooth base for painting without a lot of added weight. The 182 has 1/16" balsa skin on the wings and is powered by a Super Tigre .75. So to all you fiberglass expert I say please enlighten me! Thank you!
06-13-2013, 01:43 PM
#3
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RE: What weight of fiberglass cloth do you use?
I generally use 1/2 oz on the tail surfaces and 1.2-1.5 oz on the rest of the airframe. In my experience the additional weight is negligible and the heavier cloth is easier to apply. Plus, I don't sand through it nearly as often during the finishing stages. My .02 cents of course.
06-13-2013, 04:00 PM
#4
RE: What weight of fiberglass cloth do you use?
ORIGINAL: Chad Veich
I generally use 1/2 oz on the tail surfaces and 1.2-1.5 oz on the rest of the airframe. In my experience the additional weight is negligible and the heavier cloth is easier to apply. Plus, I don't sand through it nearly as often during the finishing stages. My .02 cents of course.
I generally use 1/2 oz on the tail surfaces and 1.2-1.5 oz on the rest of the airframe. In my experience the additional weight is negligible and the heavier cloth is easier to apply. Plus, I don't sand through it nearly as often during the finishing stages. My .02 cents of course.
I have to disagree about any added strength from using cloth. For one, it is a more durable finish on the surface. Also, There is added skin strength. It may be marginal, but it is better than not using cloth. While we used heavier cloth in the center section, many pylon racers, including F1 (models) rely solely on the cloth in the center for the center section joint strength. No spar. Those aircraft are high G and heavy loaded on that joint. Unlike most of the scale models. Unless it is a hot rod, heavy metal, WW2 bird!
No comes the question about what type of resin! lol
06-13-2013, 05:00 PM
#5
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RE: What weight of fiberglass cloth do you use?
I would agree that it provides more strength than just balsa, and also on the ding resistance, but I think the strength gain from 1 oz cloth and down is not too much over the balsa sheeting.
Sounds like a job for the Mythbusters!
"What % increase in strength is gained by X oz weight cloth filled with an additional Y oz of resin?"
whit
Sounds like a job for the Mythbusters!
"What % increase in strength is gained by X oz weight cloth filled with an additional Y oz of resin?"
whit
06-13-2013, 06:33 PM
#7
RE: What weight of fiberglass cloth do you use?
ORIGINAL: wphilb
I would agree that it provides more strength than just balsa, and also on the ding resistance, but I think the strength gain from 1 oz cloth and down is not too much over the balsa sheeting.
Sounds like a job for the Mythbusters!
''What % increase in strength is gained by X oz weight cloth filled with an additional Y oz of resin?''
whit
I would agree that it provides more strength than just balsa, and also on the ding resistance, but I think the strength gain from 1 oz cloth and down is not too much over the balsa sheeting.
Sounds like a job for the Mythbusters!
''What % increase in strength is gained by X oz weight cloth filled with an additional Y oz of resin?''
whit
perfect fabric/resin ration is 70/30 (by volume) for maximum strength, but this is basically impossible to get in a hand layup. typically you want a 60/40 for maximum strength for minimum weight with a hand layup, but even this is hard to attain without allot of experience.. Any extra resin is just more weight.
As far as what I use, i used 3/4oz for sheeting nearly everything, unless the sheeting is very thin (less than 3/32") or is contest grade, in which case as long as it is in front of the CG, i'll used 1 1/2oz. Now if its an all composite part, thats an entirely new topic!
