Fore-aft backlash in the control stick

[Battson]

Did anyone figure out how to remove this backlash / free play fore and aft?
It seems to come from the spherical rod end bearings and also from the clearance at the stick mounting brackets.

I have another backlash issue left and right because there's a tiny bit of slop in the brackets where the sticks bolt on. A small clearance down there translates to quite a lot of backlash at the top of the stick where the grip is.
If I were building again - I would make sure I drilled the bolt holes for the stick mounting brackets *slightly* out of line, L and R, so the bolts pull those brackets hard up against the stick's torque tube welded flanges / bushes.

I don't really mind it, but I do notice it sometimes, now that I'm used to the feel of the plane.

[Mark Goldberg]

Jonathan, at times in the control stick assy the bolt holes can become a little loose. You might consider going to a slightly over size bolt, and reaming the holes to the size of the over size bolt. I would only go up in size a very small amount so you still have good edge margin. Mark

[Enewton57]

You could try close tolerance bolts - most AN bolts are undersized, the close tolerance ones are true to size.

[jaredyates]

I tried turning a 5/16 bolt down to the same diameter as a reamer that I found. The fit was good on the bracket, but still a bit sloppy on the stick. Sometime when I have the plane out of service for a while I'll remove the stick, weld in a new bushing, and get a more round and evenly sized hole. On a recent visit to Zane's kit I checked his slop and it was much less than mine in its original configuration. His is about 60 serial numbers newer than mine, so I don't know if it is production improvement or just coincidence. I'll say that even mine is small enough that I'm not going to stop flying just to fix it.

[Battson]

For me the slop isn't cause by the bolts. I already addressed that problem during the build.
It seems to come from the spherical rod end bearings and also from the clearance at the stick mounting brackets
The brackets I'm referring to are the ones which bolt onto the fuselage frame (4 bolts).

[alaskabearhawk]

The bearings shouldn't have any play if they are new. Have you considered wrapping a piece of thin brass wire around the tube in the space between the stop rings and mount as a spacer?

[Battson]

They didn't to start with. After say a hundred hours, they have developed a small but constant space for free-play. I haven't disassembled to investigate.

The brass wire idea is a good one I think. Softer and sacrificial.