Frank's next repair assignment- Horizon Pulse 60 Landing gear strengthening

[Frank v B]

Picked up a brand new, assembled, Horizon Hobbies Pulse 60 with a Saito 4 stroke 125 in the nose.

The work order:
- strengthen the landing gear.  These have a habit of ripping out because of the short landing gear plate which cannot stop the long landing gear legs from acting like huge levers and ripping it apart.  The owner has another one with an electric motor and I have had to repair it before.
- replace the small wheels and wheel pants with new 4 1/2" wheels.  This customer flies off grass.

Approach is still to be decided but the first step is always to take it apart, mark all the settings and orientations (needle valve 4 turns open from fully closed, mark fuel feed and pressure lines, orientation of the tank (up and down).  All these are put into a box.

Now to get the grey matter going and solve the problem.

Frank

[Frank v B]

Putting the grey matter to work:

- tried to split the covering and peel it back so it could be re-used but the colour separated from the plastic.  Have cut the covering back to the corners.

Approach-
step 1- fill in the little step that holds the landing gear with wood so it is flush with the main part of the nose
step 2- add a solid piece of plywood from the leading edge of the wing to the very front of the fuselage.
step 3- re-attach the landing gear using the same bolts and the same attachment points.


Step 1 photographs
- cut a piece of wood the size of the step.  The thickness needs to bring it flush with the rest of the bottom piece.  (Photo 66).  Mark the orientation because nothing is ever symmetrical.  I used an arrow on the bottom side to denote the front.  (See photo 69)
- mark the two LG attachment holes onto the plywood insert by inserting two sharpened dowels into the two attachment points (photo 67).  Add some paint to the top of the dowels.  I used dark blue Dollar store paint and applied it with a tooth pick (photo 68).
- carefully place the piece of wood in the correct place and push down so the paint transfers onto the plate (photo 69) and drill it out at the paint spots.

[Frank v B]

Gluing in the first brace:

- sanded the left-over covering so the epoxy would adhere.
- applied 15 minute epoxy* and dropped 2 pieces of carbon veil over the joints  Photo 70
- placed the plywood brace over the carbon and pushed out all the air. (Photo 71)
- placed waxed paper on top and placed one #64 rubber band over the plate to keep it pushed down and centered. (Photo 72)
- placed a piece of balsa at the wing hold-down under another rubber band to keep it flat and push it against the former.

The waxed paper is used for two reasons:
i) to stop the glue from sticking to everything
ii) to flatten the fibres so no sanding is required.

Frank

* Bruce, that's 2 hands' worth of fingers and one foot's worth of toes.   I have not abandoned 5 minute epoxy!

[piker]

Will you be converting to electric?

[Frank v B]

Piker,

No.  This customer has two identical planes.  This new one is gas, the other is electric.

It is really weird working on a plane that has a muffler on it.  It has been years for me.

Frank

[Frank v B]

Installing the plywood LG plate.

- made the plywood plate and shaped the edges and the two dowels to help mark the bolt holes- (Photo 73)
- marked the bolt holes on the plate by pushing it down on the dowels covered with a drop of blue paint. (Photo 75)
- Put a a drop of oil on the bolts so any errant glue will not stick.  Also put drop down the hole and into the blind nut below (Photo 76)
- cover the wood structure with glue and install the plywood plate.  The two bolts and large washers are used to clamp down the plywood.  Rubber bands hold the front.

Off to lunch so it can dry.

Frank

[bweaver]

Installing the plywood LG plate.

- made the plywood plate and shaped the edges and the two dowels to help mark the bolt holes- (Photo 73)
- marked the bolt holes on the plate by pushing it down on the dowels covered with a drop of blue paint. (Photo 75)
- Put a a drop of oil on the bolts so any errant glue will not stick.  Also put drop down the hole and into the blind nut below (Photo 76)
- cover the wood structure with glue and install the plywood plate.  The two bolts and large washers are used to clamp down the plywood.  Rubber bands hold the front.

Off to lunch so it can dry.

Frank

@Frank v B Does it have to be blue paint, or will any other colour do?  I know where there is a colour-match for that blue! 

[Frank v B]

Bruce,

Of course any colour would do.  You probably can even use a drop of blood because of your dexterity in wielding your Xacto knife. 
There is a reason you married a nurse.  

Frank

[Frank v B]

Keep going!!!!

- removed the old wheels and wheel pants and installed the new, much larger, wheels.  Comparison (Photo 78), the new landing gear (Photo 80).
- filled the edges of the plywood with spackling and is now drying. (Photo 79)  Sorry about the focus issue, Andy.
- picked out the covering for a close match from 5 different reds in my shop.

Frank

[Frank v B]

Final stuff before re-assembling everything:
- fibreglassed two bays inside. This fibreglass adhered to the bottom of the new plywood plate.  Covered it with wax paper.  It had to be between the formers because the tank fits very snugly here. See photo 82
- covered the new bottom plate with Monokote and cut through the bolt holes. See photo 85


Frank

[octagon]

Nice Job Frank