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Old Mar 23, 2009, 09:30 AM
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Jack
USA, ME, Ellsworth
Joined May 2008
18,096 Posts
Tuffy - The Landing Gear Build, Part One of Two Parts

This is a time honored design for a landing gear, I do not take credit for inventing it. It dates back to the 40's or 50's and has been seen and described in many other threads here in the past. I'm just sharing my build of it.

The landing gear consists of three parts, a foam collar, a plywood shoe, and the wire axle itself.

The collar is really optional, if you prefer the "U" shape can be bent to the width of the fuselage without the collar for a more narrow setup. And the shoe can just rest directly on the bottom of the fuselage.

The landing gear collar is a "U" shaped piece of foam that will wrap about the fuselage directly below the wing hold down dowels. It protects the fuselage sides and bottom against chafing by the landing gear when it is mounted.

01 - Cut a piece of FFF 2-1/4" x 7-1/8". Mark two lines 2" apart (the width across the fuselage) so they are centered on the long dimension.

02 - With the plastic side down, cut shallow (not through to the plastic on the other side) 45 degrees bevels along both sides of the lines so that the two end pieces can be folded up to form the "U" shaped collar.

03 - On the plastic covered side, bevel the edges 45 degrees on all for sides.

04 - The folded bevels and beveled edges are seen here, this is the way it will look fitted around the fuselage.

05, 06 - Cover the plastic covered side with colored package sealing tape.

07 - The collar is seen fitted to the fuselage. It will be held in place by friction and the landing gear itrself.

08 - The landing gear shoe fits up against the collar on the bottom of the fuselage and has a channel that locates and restrains the axle. At the same time it serves as a pivot point so the wheels and axle can rotate to absorb landing shocks.

Cut a piece of 2-1/4" x 2-1/2" 3/32" birch plywood. Cut two popsicle sticks to 2-1/4" leng and epoxy them across the 2-1/4" width. Leaving a gap between them that will accept the wire used for the landing gear (I used .078" or 5/64" piano wire for mine).

Then file or sand two rounded grooves in the ends of the gaps between the popsicle sticks. The landing gear uprights will go up through those grooves and along the fuselage sides.

09 - The other side of the shoe has three 3M Command Poster Strips on it. These are double sided adhesive strips that will keep the shoe from sliding on the collar. Once the collar and shoe have been put together, you can leave them that way for storage or transport off of the plane.

Next, bend the one piece landing gear and wheel axles from a piece of .078" or 5/64" piano wire. A piece of wire 18" or longer is needed.

10 - I use a vise and short length of 1/4" O.D. steel brake line tubing for a bending tool. That tool, along with the vise, will give you full control of the bend points. If you don't have a vise, a pair of Vise-Grip pliers will work to hold the wire as it is bent. You can get the brake line tubing from the scrap barrel at a friendly brake shop or buy a short length at an auto parts store. Cut the end of the tube square and round the sharp edges with a file. You'll treasure this tool once you have used it.

First bend the "U" shape that will wrap across the bottom and up the sides of the fuselage.

11 - Lay out a 20"long piece of masking tape sticky side up, lay the wire centered on it, fold the tape in half around the wire. Make a mark on the masking tape at the center of the wire. Then make two marks 1-3/16" inches to each side of the center mark. The resulting 2-3/8" width represents the width of the fuselage with the landing gear collar wrapped around it.

12 - Clamp the wire in the vise with the red mark even with the end of the vise jaw. Slide the bending tool over the wire and masking tape and into contact with the vise jaw. The bend the wire to one side, keeping it horizontal, until it is about a 90 degree bend. It will spring back slightly.

13 - Slide the bending tool off and finish the bend by hitting it gently at the bend point a couple of times with a soft hammer. That will produce a nice right angle bend.

14 - Lay the right angle bend on top of the vise jaws and put the other red mark even with the end of the jaw. Use the bending tool to bend the wire to form the "U". The wire is clamped at a slight downward angle because the previous bend is on top of the jaws, keeping the bend level and on the same plane as the first bend.

15 - The finished "U" bend is seen. The wire should lay flat on the bench. If necessary, bend one wire up or down until the "U" lays flat and bend the side to get it squared away.

To be continued...

Jack
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Last edited by jackerbes; Mar 23, 2009 at 01:16 PM. Reason: Add a comment (iin red)
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