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Posted by TomFlyer | Sep 30, 2018 @ 09:31 AM | 3,841 Views
1. Painted Mylars are a little involved, but save time in wing construction by eliminating the steps of filling pin holes and primer painting of the wing. The way that I size the Mylar is to lay the sheet over the full size plan view drawing, and with a fine point Sharpie marker pen and straight edge make hte TE 1/8" over and the LE 1/8" under. This way I have material to trim straight for the TE. The LE cloth (FG,CF, or Kevlar) naturally runs out beyond the Mylar to wrap the LE when bagging. Cut as much of the Mylar with a straight edge as possible. The curved wing tip is cut with scissors. On the smooth side of they Mylar, apply two coats of Part-all #2 wax. Apply and buff the first coat with in a minute. Wait 30 minutes and apply the second coat and buff out with in 1 minute. The reason for multiple coats of wax is to be sure that you have not missed amy spots. After an hour or more, apply the PVA. This takes some practice as the PVA is not easy to work with. I add up to 25% water to my PVA plus a few drops of dishwasher drying aid called "FINISH Jet-Dry". It helps break the surface tension and make the PVA flow better. I use my spray gun to apply the PVA . You can also brush it on then take a wet cloth to remove excess PVA. the key is complete coverage. The PVA needs to dry several hours or over night. Now you are ready for paint, but how do you handle the mylars without touching the paint? Use some Duct Tape of the top side...Continue Reading
Posted by TomFlyer | Dec 31, 2009 @ 11:35 AM | 9,066 Views
This is the thread that I did on my next method of making an accurate and durable leadign edge for a slope plane (Barrcuda). https://www.rcgroups.com/forums/show....php?t=1154522
Posted by TomFlyer | Nov 28, 2009 @ 12:16 PM | 9,415 Views
I have been building slope wings with different leading edges in an attempt to figure out the most durable, most accurate, and easiest to repair. I started with the standard bass wood LE carved and sanded to shape using templates for accuracy.

Next I did a "cast" LE by making a mold using a the foam core cut by CNC guided hot wire. Very accurate, but very time consuming. A little trickey to match up the cast LE with the wing as it has to be cut back at the proper angle so the two parts mate properly. This is a related thread that has some pictures: https://www.rcgroups.com/forums/showthread.php?t=650026

Next I did the wrap the extra CF around the LE as seen in this thread:https://www.rcgroups.com/forums/show....php?t=1074863

It was pretty labor intensive to sand the epoxy off down to the proper cross section. More difficult than sanding a bass wood LE, but more durable on the slope.

Next was a method that is in this thread: http://www.favonius.com/soaring/bagging/bagging.htm
This required double bagging, and a lot of final sanding for the LE. It came out almost as accurate as the molded LE method.

Next method is going to be the best yet (I hope). I plan of bagging a foam core that has an accurate LE, cut off the LE with a 1/8 inch wide table saw blade, replace the foam in the LE with epoxy and microballoones, put on an 1/8 inch thick piece of bass wood, sand that to shape and then glue the hardened LE back onto the wing. Then bag on the final layer of glass for a nice finish. I will probably do a mini-build thread on this.
Posted by TomFlyer | Jan 28, 2008 @ 08:03 PM | 9,852 Views
How do I put one on my old threads into my "Blog"?