Repair Blog

Perfect Wing Repair

Sun, 21 Feb 2010 21:04:55 -0600

One day I was sitting quietly minding my own business whenI see an email arrives. It is from a fellow from RCGroups who had a problem. It seems he was landing one day and missed and hit his timers shin. Crushed the leading edge of his nice Pike Perfect. He was talking to Glauco and wanted to know if Glauco would fix it for him. Glauco kindly refused but referred the fellow to me. I had him send pictures so I knew what I was getting into and saw that I had some parts from Tony’s Perfect SL that would fit the bill. As it turned out I sold this fellow my Sport Tube awhile back so he loaded the center panel in and shipped it off to me. It arrived safe and sound and I did my normal thing and immediately got Brendan to help me pull out the table saw.

I left out the part where I epoxied in the donor piece and glassed the seam. Basically it’s not very exciting and it is hard to take pictures with all the epoxy around. Basically it is similar to how I do the fuselages but without the breather layer and paper towels. I sand the bump off where the glass layer is and fill with putty. Sand smooth and prime. Sand a few applications of primer until things are smooth. Mask and paint with Pike Green. Sand buff and polish. Waallahh! Smooth as baby’s bottom and you would have to look hard to see that it was damaged.

Spektrum AR6250 Antenna Extension

Fri, 8 Jan 2010 12:22:30 -0600

This is not really a repair, but a modification that I hope will make installation of the AR6250 carbon receive a little flexible. The project is inspired by this thread.

I have a Spektrum AR6250 that I want to install in a hand launch glider. For CG purposes I try to keep all radio components as far forward as possible, but having the antennas sticking out of a carbon pod in the nose makes hand catches a little tricky.

Extending the antennas so they can exit the pod under the wing solves this problem. It seems the original poster of the thread got out of Spektrum altogether, so not sure if anyone else has tested this solution. The connectors plug in fine, I added a bit of hot glue for strain relief, and also reversed the direction the antennas exit to better suit my plane's configuration.

The rest of the plane is still under construction, so it may be a little while before it gets tested, but just wanted to pass on an idea that, in principle, should work.

I bought the items referenced in the first post of the above thread.

Forgot to take pictures before taking the receiver apart (first one is the stock image from the manufacturer.) In the second picture, you can see the original, shorter antennas and how much length is gained with the new ones. Don't forget to strip off the shielding in the last 31mm!

Regards,
Chris

Serious Fuselage Repair

Wed, 9 Sep 2009 12:07:15 -0500

By Mark Miller

This was the repair I did to Brendan’s green zebra Pike Superior. We had the old white fuselage which was decent in the front but the fin was pretty sad. So, I cut the old part off and grafted on the fin front the green Superior. You can use this method of repair on a fuselage that has been broken in two also.

Donor Fin Meets Fuselage

Using Old Fuselage As a Form. Plastic Sheet As a Barrier

Carbon Doubler Laid Up

Nylon Taffeta As a Breather/Barrier

Layer of Paper Towel

Electrical Tape Adds Pressure to Squeeze Out Excess Epoxy

Doubler Comes Off Form

Cut Doubler So It Fits Inside Of Fuselage

Check Fit In Fin

Epoxy Doubler In Front Section

Now install pushrods and make sure things fit and work properly before joining permanently.

After making sure things work well, coat parts with epoxy and slide pieces together.

Tape an aluminum angle iron to the front of the fuselage. This will align both sections in both a vertical and horizontal axis.

Then check stab alignment with wing and twist rear section to adjust.

Once things are aligned tape rear section to hold it in place to cure.

Paint with your choice of paint. Sit back and admire your finished product.

The finishing touch is the new Samba sticker. Finished weight without radio gear but with pushrods, canopy and stabs is 15.7 ounces. I’d say pretty close to a new piece.

Common Composite Fuselage Repairs

Tue, 27 Jan 2009 03:13:18 -0600

By Mark Miller

Brendan had a tough year last year but not to bad when you consider he had only been flying for less than a year. Here are some photos of a fuselage repair I did last year for Brendan. The subject today is the green Pike Superior fuselage with a good crack.

Steps.....

First sand the area to clean it up. If the area is soft or completely broken firm up the area with some CA.

Then sand a "V" shape into the fuselage so that the bottom of the V is almost completely through the fuselage at the crack and thin up to the surface about 2.5" fore and aft of the crack. Again, if the fuselage is soft firm up with thin CA.

Apply a layer of thin lamination epoxy like West Systems to the area. Then apply a layer of carbon cloth over the crack area and about 2" fore and aft of the crack. Next a double wrap of 2 ounce glass cloth about 2.5" fore and aft of the crack. Brush on a layer of epoxy.

Next take a 1" wide ribbon of nylon taffeta or rip stop. You can usually find some at a local fabric store. I was going to look in Michaels or Hobby Lobby ( the craft store not the hobby shop) to see if they have taffeta ribbon. It might be easier to find. I have a few hundred feet of it from a high start company I bought out. Starting from an area before the epoxy is on the fuselage tape an end of the fabric to the fuselage and wrap over the epoxy area to after the epoxy area. Tape the end. You want to wrap firmly but it is not that important to over do it.

Next take 2 layers of paper towel and cover the area. Then with vinyl electrical tape wrap over the paper towel. Stretch the tape out as you wrap as this will provide pressure over the patch.

Let the fuselage cure for 24 hours and unwrap the tape, towel and nylon cloth. The nylon will act as a barrier film and allow the excess epoxy to pass through it and let the towel soak it up. the nylon will not stick to the epoxy and will easily peel off. The area will just need a very light sanding and will be stronger than new.

Mark Miller

Tale of Two Pikes

Tue, 27 Jan 2009 02:11:02 -0600

By Mark Miller

As we all know, Brendan had some issues with the two Pike Superiors in our family. I had a Green and orange zebra Pike that he liked a lot. He got a good deal on a white one from Jeffery Walters and decided to buy it. Due to some unexplained problem he crashed my zebra Pike when it had no control on launch. The right tip panel was toast but the rest was unscathed.
Last Wednesday he crashed his white one when he hooked his chair when putting tension on the winch line. The plane was very much broken. The good part of this bad experience is that one of the unbroken pieces of his Pike was the very end part of the right tip. I look at it and see the piece needed to fix my zebra Pike. Here are some photos of what we did to put it all back together.
Time. 15 minutes after Brendan gets home from the field and Dad measures things and gets out the table saw. Cut the tip off of the donor wing and make a foam filler and put unicarbon on the top and bottom to reinforce the seam. Epoxy all of the parts together and clamp over night.
The next day we sand a depression over the seam and fill it with unicarbon and a few layers of 2 oz. glass cloth. Sand level and coat with filler. Sand smooth and spray with primer. Sand smooth. We are now ready to paint. I’m not sure if we will do that now or fly the Gateway in primer and make it pretty later.

Mark and Brendan Miller