Patrol Change in Wheel to Wheel Distance

[Steve W]

I've never heard witness paint referred to as thread locker. Bob said thread lock. If you qooqle thread lock, there is no reference to witness paint. LokTite is a brand name of a product such as Keenex is to tissue.

[jaredyates]

You'll want to seal those threads with something to stop them from leaking, either a blue thread locking product or a thread sealing product like Loctite 567. I think folks who are calling torque seal thread locker might need more information!

[Steve W]

Yea for sure. Paint has, however, been used to lock threads in a pinch but on THREADS within a union between two devices, not the head of a bolt or whatever and expect it to work as a lock.
I have plugs installed at the bottom of the threads which sealed off the fluid just fine. I may have to remove them if I have to continue further in the shaft with more threads. Not sure if I used a quality thread seal on those or plumbers 555. Hopefully the latter which may make their removal easier.

[Bcone1381]

It seems to me like I need some confirmation. Lets say I install my gear on my tube fuselage with no wings, or engine installed. I adjust my shock strut into the threaded rod end bearing so that wheel spacing is 68." It only weighs a few hundred pounds and the springs inside each strut are not compressed at all. I suspect I have mis adjusted things.

Because then let then say I install the wings, cover the fuselage, seats, instrument panel, engine, prop, and with it the aircraft ready the gear spread changed from 68 " to lets say 70" due 800 pounds of additional weight applied to the gear. Now I need to re-adjust that wheel spacing back to 68". Is that right?

[Mark Goldberg]

Yes. It is almost always required to do some adjustment of the rod end bearings on the shock struts when you have your plane with all the weight on it and ready to fly. Maybe you guess correctly and set it before hand as needed. But usually some adjustment is needed. Mark

[Nev]

Is there a recommended “set position” of exposed threads when installing the gear struts to give the best chance of correct spacing for each aircraft type ?

Would it be possible for people to measure and post below the amount of exposed thread and their aircraft type ? I’m selfishly trying to cut down on my workload when I install the gear

[Steve W]

Nev, I was at the plane today and removed my shocks. I should have a wheel distance for you hopefully tomorrow. I’m at 64.5” center to center now with no weight on the wheels. My stance was 70.5” with empty plane weight. I shortened the strut length and will re-assemble tomorrow. I will have new numbers for you which should get you close.

[Bcone1381]

That would be awesome.

[Steve W]

Unable to do the install. The top part of the strut interferes with the control yoke so will have to shorten the bottom end of my struts. Not the end of the world but have the material on hand and will give me a couple days work.

[Bcone1381]

I had some issues with this too. I lowered the head of the rod end bearing down to give me more space between the control stick's Torque Tube and the two Shock Struts. There is quite a bit of adjustment here. The thread length on the rod end bearing is generous.


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[Steve W]

OK, so I had a chance to install the shock struts. The deep freeze that set in a month ago that the US just witnessed this last week has moved on so I was able to work in the hangar without freezing my extremities.
I cut 1/2" off each strut and assembled as per the drawings. I engaged 11/16" of threads of the rod ends. I am able to lift the whole plane off the ground. I previously built lifting points at the front wing attachments for future float install. My plane is at the basic empty weight of 1192 lbs. The center to center distance at axle height with no weight on the struts is 62.5". This is a tail "on the ground attitude" with the wheels just off the surface. With the weight on the wheels, the distance is now 68.5".