slotdr

Hi all, haven't been on this thread for a while, bought a Honey Bee King 2 so I neglected my AXE CP. Back to the AXE CP, how much play should there be between the blade grip and the center hub, should it be snug?, I bought a after market CNC center hub and there was a lot of play so I put the original hub back on and noticed that when I tighten the Feathering Spindle the blade grips are tight, using red O rings with original center hub and the black O rings with the after market center hub. One is to snug and the other has play in it. What next Thanks

Shadow99

Joey,

Are you using the MicroHeli center hub? The blade grips should rotate within the center hub quite easily, but shouldn't have any slop or side to side play. I use the red dampner O-rings in my hub, lube them up with some light grease, also lube the shims on either side of the hub. If the blade grips are still too tight on the feathering spindle, with both screws tight, you can remove some of the material on the back side of the blade grip with a file, then reinstall them on the spindle & check for movement.
I've had a feathering spindle that was too long, and had to be ground shorter to fit the grips. Make sure the bearings and spacer are fully pressed into the blade grips (I use a 4mm hex wrench to press the bearings into the blade grips and fully seat them).

Rick

cletusjenkins

Mine didnt fit snug b/c i didnt realize that the blade grips had 3 bearings in them that have to be transfered to the new blade grips...

slotdr

With the stock center hub the grips are snug, all bearings are in the blade grip. with the MicroHeli center hub it is loose, I was going to grind down the feathering shaft.

Shadow99

Joey,
Be sure to only remove a little bit 0.005" or less at a time, I used a file went I did mine. You can always REMOVE more of the feathering spindle, but it's really hard to put material back on to make in longer again. You could add some SHIMS or thin washers rather than grind the spindle to fit, the choice is yours.

Rick

Zep99

I recently purchased a full set of uHeli CNC parts for my Axe (stabilizer hub assy, swash plate, center hub and grips). I certainly noticed the same fit issue with the CNC Center Hub and blade grips. In my case, I started out trying to get the CNC center hub and CNC grips installed. Using the uHeli black o-rings, there's a good 0.1" of play or so (I haven't tried out the plastic grips on the CNC hub).

Based on a suggestion from another forum/thread, I tried using the HeliMax red o-rings instead to de-tolerance the sloppy fit. The slop was indeed taken up, but I was skeptical as to how the blade grips were going to remain nicely centered relative to the main shaft axis under power. Test hovering (with the full-up CNC rig) revealed a strange oscillation, especially when giving a cyclic input. The heli would "wobble" around the main shaft axis a few times a second. However, the heli was otherwise not trying to shake itself apart, so it's not clear that this is a grip/blade centering/balance issue. At any rate, not fantastic.

Tonight I swapped out the CNC center hub and grips for the stock plastic hub and grips (keeping the CNC stabilizer hub assy and CNC swash in place). Works great, so clearly the problem is in the hub and/or grips.

I'm not excited about grinding down the feathering spindle, and I'm also baffled that the uHeli parts, which in every other way seem to be truly precision machined with perfect fits, are WAY OFF when it comes to "gap-osis" on the feathering spindle.

As Shadow99 suggests, I'll probably look into finding the right washers to get a nice fit (as heli-max used in the first place). Another variation I could try is the CNC center hub with plastic blade grips, in case the grips for some reason are binding and causing weird cyclic behavior.

Any thoughts?