Randy, most of this stuff should be in the archives but here is a quick lesson. Selvage edge=the two edges of the cloth as it comes off of a roll of material. Unidirectional cloth=most fibers running in one direction off of a roll of material/parallel with the selvage edge with some fibers running perpendicular just to hold the main fibers in place.
Bidirectional cloth=strands of fibers interwoven, some strands running parallel to selvage edge and some running perpendicular to the selvage edge. Some cloths have equal numbers of fibers running both directions, some have more numbers in one direction or the other. Biaxial cloth=two separate layers of unidirectional fibers running at 45 degrees to the selvage edges at 90 degrees to one another. These two layers are lightly stitched with crossing fibers just to hold the two layers in place. In the old days you had to lay down one layer of unidirectional cloth, wet it out with resin then lay down a second layer and wet it out. This fabric is great for covering wing surfaces because when you roll it off of a roll onto a wing the strands of fiberglass are already at two opposing 45 degree angles to the leading edge of a wing for example. Triaxial cloth=same as biaxial but has one layer of unidirectional strands parallel to selvage edge. Flox=is chopped up cotton fibers that can be mixed with already mixed resins to create a thick structural filler for making structural joints. Micro=micro spheres (glass balls is what I call them) mixed with already mixed resins to form a light weight filler (like bondo). The fiberglass cloth is laid on the surface before the micro cures. (then add more pure resin to wet out cloth) This is usually used to cover the foam surface, which is porous, before you lay fiberglass cloth on it. The reason for this is to save weight. You can use pure resin over foam surfaces but it will run down into the porous surface of the foam and make your part heavier. If you use the micro mix over the foam first it will fill the pores of the foam and save weight. You can use micro like you would use bondo to fill low areas that you want to level on a wing or fuselage surface. You can use micro to fill corners where you need to adjoin (for example) a wing rib to the spar. Wetting out cloth=I usually lay the cloth onto my parts then wet out with resin, but sometimes depending on the situation lay pieces of cloth on plastic and wet out with resin, then pick up the whole thing and lay it on the part, then peel off plastic. It is a personal preference as to how you proceed. Landing gear=fiberglass landing gear legs are made from unidirection fibers. The bidirectional or biaxial cloth are used to wrap around the leg to help contain the unidirectional fibers from seperating or splitting apart. It makes the leg stronger is the bottom line. Hope this gives you some directions to think about. Larry H. Subject: KR> "HELP" Q&A I have some questions on the repairs I'm doing on my KR not necessarily in order. What is Biaxial cloth is it the same thing that i have to cover my wing stubs? it says to use this on my landing gear is it necessary? . And peelply what is it and how do i use it!!!And i also keep seeing flox what is this and how do i use it? anyway i appreciate the help I'm trying to replace the foam on my wing stubs and install fixed gear!!! also do i brush out the aeropoxy first then lay down the cloth or lay down the cloth then brush on the aeropoxy? . also what is the term wetting it out? thank you>From: "randy white" <zakk_1998...@msn.com> >Reply-To: KRnet <kr...@mylist.net> >To: kr...@mylist.net >Subject: KR> FIXED GEAR >Date: Tue, 28 Nov 2006 08:42:43 -0800 > >Does anybody have some pictures of the instulation of fixed gear for a tail >drager!!!my instructions arent very clear!! thanx Randy maddyhome.com/krsrch/index.jsp to UNsubscribe from KRnet, send a message to krnet-le...@mylist.net please see other KRnet info at http://www.krnet.org/info.html
