Repairing broken landing gear on a .40 size biplane

[Frank v B]

A member had a biplane built by another member. The landing gear broke.  Photo 95
This plane was a kit and it appears to have a weakness built into it.

To remedy it I did the following:
- cut away all old glue and loose balsa. Photo 96.
- cut away all covering near the repair area. Photo 97.
- glue the old plywood mount back in place with epoxy. Photo 98.
- add fibreglass cloth over the balsa area.
- add a plywood brace to cover the entire flat area.
- add fibreglass cloth on top of the plywood.
- screw the LG back in place.

Frank

[msatin]

Very nice!

[Frank v B]

The next 2 steps

- add fibreglass cloth over the balsa area.  See photos 08 and 09.  The waxed paper is taped on so the edges of the glass lie flat while the glue dries.
- add a plywood brace to cover the entire flat area. Photo 10- the paper outline lies on the 1/16" plywood for the next step.  Cut it out, glue it on top of the fibreglass.

Frank

[Frank v B]

Added a plywood brace on top of the layer of fibreglass.  Epoxied in place.

photo 13 shows the 1/16 plywood brace.
photo 14 shows the plywood plate scored so it can conform to the shape.  Still in one piece.
photo 15 shows the plywood plate taped and clamped in place.

Next is 1/2 ounce fibreglass over the entire repair.

Frank

[Frank v B]

Last step before covering

- added a layer of fibreglass tape (about 3 oz, tightly woven, long enough to wrap up the sides) to the base of the landing gear.
- on top of that added 1/2 oz light cloth to hold it all down.

Used 5 minute epoxy thinned about 50% with rubbing alcohol.
put waxed paper on top with masking tape so it held everything flat while it curled up the fuse side.

Next:
- sanding 
- covering
- sending it back to its rightful owner.

Frank

[Frank v B]

- sanded the new fibreglass. Note- the area under the landing gear now has an extra 3 layers of fibreglass and one extra layer of plywood. Photo 323
- covered the repair area in new red covering.
- drilled and attached the landing gear. Photos 324 and 325. Note:I added one extra screw...because I could. 

FINISHED!!!!

The problem started when the plane rejected the landing gear on a hardish landing.  Now the landing gear will stay intact but will reject the fuselage on a hard landing. 

Frank