Carden Edge Restoration

[Matchless]

I thought I'd throw a thread up about my restoration of a Carden 35% Edge.

Flashback about 6 months, and I was beating foamies to death. Many of the people I was talking and flying with suggested that I get a giant scale plane to improve my precision skills. I am actually a micro flyer type guy, and have been for most of the 20 or so years I've been building and flying. (Baron knows what kind of size I'm talking about) So going bigger is pretty daunting for me.

I looked at building a 50cc bird, and even designed a new one to build. However, something I learned from restoring cars pushed me in the direction of buying something already built. You know, let the former owner take the hit. I had trouble finding the right bird though... Some were too expensive, some were not the way I wanted to go (Caps...)

Then I got lucky. At an indoor pattern competition I was running, I had the Terry behind 'Terry Built Airplanes' as a judge. We had talked a bit before about me flying something bigger. At the contest, he offered me a Carden 35% Edge. It had been crashed, but the offer was too good to pass up.....

Flash forward to today--

The airplane I brought home in my truck is the Edge that Chip Hyde won the 2002 XFC with. When I got it, what was there was in OK shape, but very repairable.

Here is the damage list.....

Right wing totally missing (removed and rekitted by a tree)
Right side of fuse cracked and splintered in several places.
Right side of Turtledeck separated
Left side of Turtledeck separated
Landing gear torn from plane and twisted
Wheel pants broken on mounts
Cannister tunnel in fuse destroyed
Lower cowling half severely damaged.
Various other small dings to fix.

The Rebuild

I started the rebuild by getting hold of a new set of landing gear from Carden for the bird. Also picked up a wing tube as the original was destroyed in the crash.
I fixed the damaged parts of the bottom of the fuse by filling with light spackle and sanding smooth. The old bolt holes were filled with epoxy to strengthen the gear blocks. Then I drilled the new gear to match the old and drilled new landing gear holes and tapped them for the bolts.

Now that the airplane is back on its legs and can stand on its own, I wanted to get the wing going. Unfortunately, since the original was gone, I had to reverse engineer the normal building process to get the incidence of the new wing right. I talked through my plan with Terry and he thought it sounded good.

I began by cutting a new root rib for the wing. I cut it using the root of the core and the phenolic as a template. I finish sanded it on the wing. Next up, I cut the ply inserts for the retention bolts. Before gluing on the inserts, I zeroed out the fuse with my incidence meter. Then I slid the rib and a scrap of phenolic on to the fuse. I glued a level on the rib on a centerline I had drawn. When everything was set to zero, I drilled from inside the fuse out through the rib to locate the holes.

With all that removed, I glued the ply inserts on the rib and drilled through them. I then cut out the rib and glued a 1/8" thick square of ply over the hole and drilled back through again. I finished this assembly by installing the 8-32 blind nuts and filling them with grease.

Pro-bond and judicious use of tape held that whole assembly in place while I cut the servo pockets and wiring holes through the rest of the wing with my hot wire tool.

[50%plane]

Cool! Great job on the rebuild!

[Baron]

Lookin' good Jeremy

[ShortBus]

lookin' good!

[Matchless]

Thanks ya'll. Next up is the wing sheeting. I sheeted it on a friend's building board last night, so I have a few good pics.......

[jack01]

Haha! I helped corrupt him!! I'm so proud of myself....

Anyway Jeremy, it looks awesome! Has your wife warmed up to it yet?

[Johnny MoJo]

Very nice Jerms..........I helped by smoking cigaretts and watching.

Love to have one of these or a Dalton. I think just building the thing would be tons of fun! Tony's threads are always art and perfection, and AeroDaves thread is inspiration for all the "little people". I must say that the wing sheeting was MUCH easier than I thought it would be.

J.

[Matchless]

After getting the root rib set, I glued in the phenolic tube and the lite ply retainer in the hole in the wing. More tape and some weight placed strategically over the tube and the glue holes kept everything straight while it dried overnight.

Sheeting - Next up was a trip to Johnny Mojo's house to use his workbench. I wanted to load this thing with plenty of weight to promote good bonds, and he had plenty of weights to load the wing with, and his bench is strong enough to hold it.

We first traced around the wing core with a big marker on his workbench to get the outline of the wing. Then I began to lay sheets down so that I covered the drawing and left enough overhang for some wiggle room. After laying out the sheets where I wanted them, Johnny and I taped them edge to edge with blue painters tape. Laying the core on the sheet gave us a quick look into whether or not we had any missaligned (we didn't ). I finished the skin by trimming off the trailing edge of the skin while leaving a 1/2" overhang.

Next up, I block sanded the entire core with 150 grit paper on a long block to smooth the surface and cleaned it with compressed air. I paid special attention to the servo boxes and the slot where the cutting wire went in to cut the phenolic tube. I spread polyurethane glue with an old credit card and set the first skin in the husk. Then the core and the other skin went in followed by the top husk. We spent a few minutes carefully aligning everything and then taped it closed with painter's tape.

We loaded a 3/4" thick masonite board on top of the curing wing and then loaded just over 500lbs of weight on top of the masonite. Just as I had hoped, the poly glue oozed out the ends of the core which told me it was foaming up nicely. We let that whole assembly sit in a corner for 24hours.

The next day, we pulled the weight off of the assembly and checked everything over. Before removing the wing from the husks, I cut away the tape and trimmed the extra sheeting down to about 1/16" left all the way around. I used a diamond cutoff wheel in my dremel to quickly cut away the extra. While the wing was still in the husks, I pulled the root out slightly and sanded the extra off to make the root rib square and then did the same thing to the tip. I also pulled the blue tape that was holding the sheeting together while gluing. The polyglue foamed up between the sheets and glued them together very tightly. Only minor sanding was necessary to get rid of the glue joint.

Now it was time to prep the leading and trailing edges of the wing and the pieces themselves. I used my razor plane to trim the sheeting down nearly to the foam, followed by a 100grit sanding bar to square it off and make sure the leading and trailing edges of the wing were straight.

I prepped the 3/8" leading and trailing edges by clamping them at one end to the bench. Then I tapered them somewhat to more closely match the taper in the wing. This was/is a big time saver as it is much easier to razor plane the wood when its clamped to the bench than on the wing. The watchout here though is to not take off too much.... Its easy to take it off, hard to put it back...

With yellow wood glue and a lot of blue tape, I glued on the leading and trailing edges. After drying for about 2 hours, I pulled the tape and had a look at my wing.

Hopefully in the next few days, I'll get to cut the aileron loose. That part of the process bothers me a bit, as I don't like cutting into a perfectly good wing.......

I've also already finished the fuse work, so I'll put up some pictures of that.....

[Matchless]

After pulling all the tape and checking the wing over thoroughly, I went to work on the leading and trailing edges. I first shaped them with my razor plane, and then went back with the sanding block to finish up. That went really quickly
I think sanding leading edges really intimidates people, but there are a few key things that make the job easy:

First, don't ever use old sandpaper. If its worn, then throw it away and get out a fresh sheet. Don't 'save money' by buying cheap sandpaper. Its really not worth it. I prefer 3M sandpaper and have been using it forever. Having several different grades is very handy as well. Finally, don't ever use sandpaper without it attached to a block. Sanding without a block is the surefire way to get bad highspots in your work.

Next up, use a razor plane. The razor plane is the easiest way to shape balsa quickly and accurately. I use a $4 Master Airscrew plane. I prefer to set mine to a very shallow setting and use a sharp blade. It takes a little longer to shape with the shallow setting (adjusted with the screws in the back), but if you set your plane to cut half as deep as you thought you should, then you have the opportunity to be twice as accurate.

With the edges shaped and sanded, I wanted to begin to mark the ailerons for cutting out. This is truly a time of measuring 4 times and cutting once. To lay out the ailerons, I started by measuring the wing I was copying. I then laid out the hingeline lightly with pen and a huge straightedge. I then marked out the 3/8" offset for the caps. When I marked this, I marked the whole setup undersized. That will give me some sanding room to clean up any mistakes.

After marking the offset, I laid out the cut marks with blue painter's tape and then duplicated this on the bottom side.

After marking the aileron, I was able to find my servo pockets. I simply measured to where I had originally placed them and cut a small hole. I then opened up the hole to the correct edges. That was enough on the wing for now.

I mentioned earlier that I had done some fuse work already. I had glued the turtledeck back in place on both sides and re-covered the torn spots. I also took a moment to grab each of the cross pieces in the fuse and tug on them a bit. I found 4 loose pieces and CA'ed them back into place. The right side of the fuse was fairly damaged as well, so I pulled the covering and CA'ed everything back straight. With the covering back in place, that side was good to go!

Inside the nose, things were pretty rough. The airplane is set up for cannisters. When it crashed, the cannisters apparently punched up and through the 'roof' of the cannister tunnel. Only a few bits of it were left. I cleaned out the walls and made a new tunnel roof from 1/16" balsa (hard stuff that had no use anywhere else). I duplicated the foam insulation covered with foil that was used in the original to insulate the airplane. With that installed, the fuse is basically ready for radio install.

I put a pic of the cowling in as well. I may replace the cowling with a new one at some point, but for now, I'll just repair the old one. Luckily, the fiberglass itself is relatively undamaged and the Cowl ring is still firmly attached. Unfortunately, the original painter used such heavy coats of paint, it comes off in sheets where it hit the ground. Frankly, the paint is the thickest I've seen (even on some of the cars I restored through the years). I'll re-paint the lower half of the cowling and make it look right.

[SleepyC]

Nice job so far!

Nothing like taking other peoples "throw aways" and making it into a piece of art!

[Propstriker]

Nice Job Jeremy!! Can`t wait to see you Huckin it around at the next indoor!!!

[Matchless]

Thanks ya'll. This really is going a lot like a car restoration so far. I think the re-finished bird will turn out pretty nicely..... : )