Bent legs and Tire wear

[Bernie RV7]

I have seriously bad inside tire wear on both sides of my recently purchased RV6..
Lots of toe out... also suspect bent legs as the left wing tip is about 3'' lower than the right. There is no firewall or fuselage distortion or damage to the engine mount.
Is there any way of knowing if the legs were factory drilled or drilled by the builder?....
What are my options of rectification .... thanks Bernie

[Jesse]

I just recently sent a set of gear legs to Lang to straighten. They turned out to be the old weaker gear legs, so Lang got a new set from Van's and drilled them to match the weld Kent. Then we had to replace the U-403-PC brake brackets to fit the factory hole where the wheel attaches. Haven't found out how the tow-in/-out changed, but this plane also had very high wear on the inside of at least one side's tire. This was a tricycle gear plane, but the process should be similar for a conventional gear model.

I see you are in Australia. I don't know if there is a place like Lang there to do this type of thing. I'm sure they would do the job if you sent them to the US, though.

[rv7charlie]

If the bend isn't too bad, it can be straightened cold in a 20 ton press. Span the bent area across two soft wood 'spacers' & press down on the bend (oriented up, obviously). Helps to have a helper, and take small 'bites', checking each time until straight.

YMMV, you didn't hear it here, etc etc.

Charlie

[RVDan]

I might suggest rising the aircraft with both gear off the ground, then using the builder manual, check the toe in/out and gear leg straightness. You can also verify which gear leg has the problem. If this is an early -6, the gear legs were match drilled to the engine mount by the builder and they could have gotten it wrong. Another possibility is that a gear leg was replaced incorrectly.

[Billythekid]

once you string the landing gear relative to the fuse CL you should be able to tell which leg is off line and be how much. to do that imho is the first place to start as its the least expensive. and of course read how it should be done in the construction manual as that too is inexpensive.

[JonJay]

You might find some clues in the logs. A bent gear leg can often result in a prop strike. It takes quite a hit to bend the gear. Very hard landing or ground loop. If you see a rebuild, new prop, wing tip work, etc... you might link those to when the gear leg got bent. Not sure that changes anything as you still need to get it fixed regardless. However, if you don't find anything in the logs, something is amiss and I would investigating further.

[rvbuilder2002]

With the sweep back angle of the round gear legs on RV's, if they get bent it also results in the toe alignment changing. If you know for sure you have at least one bent leg, it is fully possible that the inside tire wear is entirely caused by the likely toe misalignment that is the result of the bent legs.

[Dragon Master]

I had a complete description of how I fixed the problem on my six and while trying to search for pictures the #$%^ website apparently timed out and I lost it all. If your interest I corrected it by designing a laser aligner and fixed it with a small TIG weld at the top of the socket.

If you're interested send me an email and I'll look up the pictures and describe the procedure.

[Bernie RV7]

Thanks for all the information.
I spoke to the Builder of my 6 and he says he had to drill the legs during the build and they were aligned when new but went out of alignment over the last 15 years.
Ill remove the legs on the next annual and send them to Lang for straightening.
cheers

[roadrunner20]

I had a toe out when I changed from a 7A to a 7.
The mount I purchased was older & match drilled at the time, but no gear legs.
I had to purchase jig drilled legs from Vans and had a toe out on both sides.
To correct it, I oversized the gear leg holes one size with a reamer.(forgot the type) Van's was ok with + 1 size.

I raised the front end from the engine hoist bracket to dangle the gear legs.
I marked the floor with a straight line with plumb bobs over the leading edge.
Then, with the gear legs in place on the engine mount, I attached a string to the gear leg stem creating an extended line to parallel align with my leading edge line.
Once your line is parallel, check the gear leg hole to the engine mount drilled hole. You will see the offset, kind of like a crescent moon misalignment. Reshape the top gear mount hole with a dremal to match your oversized gear leg hole. Once satisfied, pass the proper size drill though the mount, gear leg hole, to match the bottom.
You will be surprised how little correction it will take on the engine mount to correct a toe out.

I hope this makes sense. If you decide to do this, send me a PM and we can discuss it. I discussed this with Van's & Lang when I did it.
Mine were so toed out, it would scuff the tires lateraly.

Update: just noticed you're in OZ.
We can discussed it by email too.