[Blain]

Fuse inverted and level. Plumb bobs in place. All line up within 1/16". Not sure if the outboard mount is too far back or if this is normal;


Looks like drilling the upper wear plates could be a problem with it this far back.
Anybody?

 

[Ron RV8]

I'm not sure that the plumb bob method will work every time due to tolerances in bending the lower part of the gear.

I clamped the centre of two 10' pieces of straight aluminum angle to the "axle mount" part of the gear, and measured between the front and rear of the angle to set the tow in / out. Watch for uneven powder coating before attaching these. This was in addition to triangulating from the tail. I was aiming for zero or a little tow out. I was close but in the end had to use a shim on one side as well.

If the triangulation is correct and the tow in / out is where you want it, the bolts pretty much end up where ever they end up. For me this resulted in a couple being close to interference items inside the fuselage and I had to grind a couple of washers to make them work.

Only one flight so far but it seems to track straight and is not squirrly so I'm happy.

 

[skylor]

Fuse inverted and level. Plumb bobs in place. All line up within 1/16". Not sure if the outboard mount is too far back or if this is normal;

Looks like drilling the upper wear plates could be a problem with it this far back.
Anybody?

A couple of key things that I discovered aligning my gear:

1. Be sure that you level the fuselage with reference to the forward floor section per the instruction manual and not the longerons as they are different (the instructions call out using the floor for the level reference here).

2. I found that following the instructions works well except that the gear legs don't necessarily sit flat against the outboard wear plates until the brackets are torqued. To prevent the alignment from changing from when they are drilled to the final torquing, I temporarily installed the axels and used ratchet straps attached to the ends of the axels to pull the outboard ends of the legs downward thus ensuring that they were flat against the wear plates before drilling. This worked pretty well for me.

3. Most -8's that I have seen (including mine) do seem to end up with the outboard gear bolts shifted towards the aft of the fuselage cut outs, but yours does seem to be a little extreme.

Skylor
RV-8 N808SJ, Flying

 

[Andy Hill]

There are old threads on this...

As Ron says, back to 1st principles:

1. Make sure the wheels point in the same direction - via angles on outside of the gear legs (essential)
2. Make sure wheels point in direction of fuselage (desirable)
3. Have a good look at where nuts will be in the fuselage for fitting / maintenance

I never quite understood what the plumb bobs were trying to achieve

 

[Blain]

There are old threads on this...

As Ron says, back to 1st principles:

1. Make sure the wheels point in the same direction - via angles on outside of the gear legs (essential)
2. Make sure wheels point in direction of fuselage (desirable)
3. Have a good look at where nuts will be in the fuselage for fitting / maintenance

I never quite understood what the plumb bobs were trying to achieve

I neglected to search before posting.
Yes, found many threads but none with a definitive answer. I do like the idea of previous respone about using rachet straps to pull the gear tight against the wear plate. Sounds like ultimately limited by the bolt placement.

 

[Blain]

How does it go? Measure twice, cut once? How about measure, square, level, laser and do it again about 50 times.

Found one of the factors contributing to the measurement from the tooling hole in the last bulkhead;

Not a good angle for the photograph but what you can see is that the tailcone is twisted. Both the longeron surface for the horizontal stabilizer and the tailwheel tube to lower tooling hole show the twist. Ended up dropping the plumb bob from the centerline of the tailwheel tube. Not sure what to do about the twist, probably should search before I ask if anyone has had the problem.

The good news is that using both plumb bob and laser lever to a target 35' away I got the gear within Vans specs 3/16" and dead square on the laser target.


Can't see the laser light in this photo but it is emitted from the level in the foreground to the square on the centerline between the legs and hits a target mark on the far wall of the shop. Did this for center and both legs.


Now the gear is centered in the pocket where it belongs.