Weight FibreglasS cloth for wing join?
 

Hi all,

Whats the prefered Fibreglass cloth in oz. for reinforcing strip on a wing centre join ? I'm doing
a high wing 74" trainer type wing , cant recall wether to use 4oz weight cloth or 6 oz ?

Dove57, There's a good chance that you will get ten different answers to your question. 74" wing span is a fairly large wing, but I'd be more interested in your estimated weight. Without knowing any more details of your airplane I would suggest two layers of the 4oz. cloth. Make one strip approximately 3" wide, and the other 6" wide.

I do it the same way. Dan

Dan ,Sorry should of been more exact the model is similar to a SIG Kadet Senior 74" span, approx weight 7.4 lbs

Is that 4oz cloth on the sheeted wing?

I suggest two layers of different widths as well except always start with the widest layer first. If you go the other way when you sand the cloth later, you will cut through the top layer at the edge of the narrow layer and end up with two layers of the same width.

I use Sonic-Tronics 6 inch fiberglass tape (around 4oz) over lapped about about two to three inches at the dihedral joint. It's a foam wing sheeted with 3/32 balsa. The planes weigh 20 pounds and are 50cc powered. I've used this method on dozens of plane. Dan..

Good advice thanks Dan, is that a Miester or Anderson warbird scratch built ?

I'm the odd ball here. I use a layer of 5.7 ounce carbon fiber fabric about 1 inch wider than the fuselage. I cover that with a layer of 3/4 ounce fiberglass cloth . All is done at one time, top and bottom, and vacuum bagged until cured. The carbon is always cut on the bias and the fiberglass cloth is there only to allow me to feather the edge without sanding into the carbon. I have never had a wing fold and I beat the crap out of them.


Scott

not a bad way to go. I did forget to mention that I too like to go out past the width of the fuselage. One, because the most stress is placed on the wing just outside the fuselage and secondly, it will keep the fuselage from digging into the wing.

Scratch built from three views. Dan.

I use the approx 6" wide automotive stuff you can get in any automotive or big box store auto section. No idea what the weight is, but it is available, cheap, and it works. Wide enough to make the saddle under 'glass (don't try to eat that one) so you don't end up smunching balsa sheeting. Attach with a thing film of spray adhesive, then finish with epoxy. Spackle to fill.