Avstar Aircraft of Washington, Inc.

10415 172nd St. E., Hangar A1
Puyallup, WA  98374
office (253)770-9964
or (253)770-0120
email:  avstarair@att.net

07-05-2004 Ask Mike! Archive
Re-installing wing wires

Hello again, Mike.

I e-mailed you late last year about my N35 project; it is going well, I'm using the late style nose bug with straight mounting. Your suggestion about shifting the bug slightly for fitting and spinner alignment worked fine. The basket is installed, and the bug is drilled and clecoed in place. I also had to do an inboard leading edge skin replacement which I am working on at home in the garage, while the fuselage is at the hangar.
My question this time is regarding re-installation of the wing wires. I got the Beech telescoping tube set (thought there would be more there than just some steel tubing cut to various lengths - for $240 !), but I've fabricated 2 short (6" X 1") steel plates to clamp onto the wire for driving, but past about 1/2 way in, I can only drive it in about 1" at a time. Then it's unclamp, move the plates back about an inch, re-clamp and drive in the next inch. Kind of a slow process. Using the tubing, there seems to be too much flex at the longer lengths to get any real impact on the wire.
Any tips on getting em' in a little quicker would be appreciated!
What do you use to actually clamp onto the wire?

Thanks again for the help, Mike!

Hi Mark,

Sounds like many steps forward in your project.

3 weeks ago, I would have only been able to answer your question with "what I've been told...", but that is no longer the case, as we just finished up a spar replacement in a V35. We wasted 4 wires (bent) and an un-godly amount of time in the shop and talking to the "pros"; I'll tell you what worked for us.

Have you kinked any of the wires? Even the slightest kink will render the wire inoperable, as the tolerances do not allow for a wiggle.

Have you checked for hinge alignment? Using a string from one end to the other make sure there is not any misalignment; as much drag as there is on the wire, the misalignment will seize the wire up. We found the best way to keep alignment was to let gravity help by setting the wing on it's leading edge; flat on the table induces a slight bow.

You are using the correct tool. I know, it doesn't look like much, but it works well with a couple of minor changes. First, we modified the short, larger diameter tube and the second longest larger tube by threading them internally 1/4-28 X 1/2 inch. Next, a 1/4-28 bolt was drilled down the center slightly larger than wire size (approx 0.075"). The threads were chased down the bolt about twice original, then inserted into a piece of 0.062 aluminum sheet drilled 1/4", and secured with a jam nut. A couple of more holes in the sheet properly placed, and this jig can be secured to the end of the spar directly in line with the spar hinge (you'll also need a spacer the same thickness as the bolt head). By screwing the tube to the fixture, you will eliminate the tubes from jumping around as much, and greatly reduce your chances of kinking. Then we used a rivet gun (starting with a 2X, finishing the last 5 feet or so with a 4X) with a set that is used to hold the dimple dies. (As the dimple dies are a 3/16" shank, the wire and inner tube fit well.)

The best lube we found to use was put on by (wing halves separated) inserting a smaller dia. wire into the hinge halves (we used 0.055" piano wire), and putting Aeroshell #5 grease on the exposed portion, then running the wire back and forth to lube the inside of the hinge links. Once the wing is back together, and on it's leading edge, you can strap the wing with ratchet straps (use blocks on the rear spar in the aileron area to keep from damaging the trailing edge, and a long 1 X 6 in the aft flap roller position through tracks, same purpose), and again find the happy spot with the smaller diameter wire. Measure the length of the spec wire so you can chart it's progress into the wing; if you hit a tough spot, you'll know where to try and massage the wing with a padded block. Don't accept the bullet-nose Beech puts on the wire, sharpen it with a grinder to give it a better approach. As the wire is inserted into the wing, apply a bit more grease. We typically got each wire in about 3 feet by hand before using the rivet gun. With enough people (wearing gloves: as the tubes collapse, you can get pinched, also they do get hot!) to keep the tubes from jumping around, use the rivet gun, changing the tubes as required for the length you're driving. The guy holding the rivet gun needs to pull the inner tube (to keep it inside the set), make sure the gun is pointed down the spar, and lean into the job as if pushing the wire in.

Sounds easy enough. Looking at time cards, we spent approx 5 hours prep time, and approx one hour in actually installing each wire, but we had success. Don't just rely on your measurement to make sure the wire is home, get a visual on them, and make sure it isn't grease that comes out of the hole you're looking at. To sum all this up, patience is the key word.

Gear green,