Spindle length issues?

[SidewaysLS4]

I have a 52mm "flybar" and 53mm "FBL" spindle combo included in my kit. I am setting up a FBL head, so I used the 53mm "long" shaft for it per the instructions. The instructions call for the "Large FBL" spindle spacers to be used as well. If the large spacers are used, the spindle screw washers will not bottom on the spindle end, and the spindle itself will not seat completely into the outer bearings. However, using the narrow spindle spacers with the longer spindle, everything fits as it should.

The only trouble I see here, is that looking from the top, the grip balls look like they could use a longer spindle so that they are 'square' (picture). And that leads to the question...what are the wide spindle spacers to be used for? If they were used with the shorter shaft, the fitment would be even worse.

So...is it possible the flybar shaft really is the 53mm version, and the FBL shaft should be around 54mm, so that the ball ends will line up with each other on a 90* perpendicular plane to the blade grips, as well allowing usage of the "wide" spindle spacers?

Ideas?

[OICU812]

Did you try to tighten the spindle bolts in? They compress in, no biggie, mine were all same measurements, worked fine. The longer one is the FBL yea.

[rablett]

Same dimensions on mine and everything went together just fine. Longer spindle and thicker spacers is to elimate delta error. Balls on blade grips need to be right on center of main shaft.

[SidewaysLS4]

Could you guys check if you are getting the spindle all the way to the outer edge of the outer radial bearing in the grips, using the long spindle/wide spacers?

Using the wide/long combo, I tightened down the grips as much as I was comfortable with (didnt want to damage the bearings by mushrooming them), then pulled strongly outward on both grips while wiggleing them to see if the thrust bearings werent seated completely or something...no change. Bearing pack depth is the same on both grips as well.

I'd be real curious if you guys are getting the spindle all the way through the outer radial bearings so as not to torque on them while tightening up this head.

[rablett]

I can confirm that the spindle comes basically all the way through the bearings on mine. I have fully tightened the spindle bolts, which very slightly compresses the head dampers of course, and no binding whatsover.
Roger

[OICU812]

Without tightening the spindle will not come to end, this is normal on any heli, it's meant to compress the dampers and firm up. Once you tighten the spindle bolts they will flush out against spindle.

[SidewaysLS4]

Well, if I'm not an idjit Got the blades on and did some spool up testing. 1600...wow, this things quiet. 1800...so when does it start making noise? 2000....pop, hit throttle hold. Well lookie there, a gap between the headblock and the grip where a 'wide' FBL spacer would now fit . I guess I wasnt pulling hard enough to seat the thrust bearings all the way...but spooling it up fixed that.

[OICU812]

You gotta trust the manual man!

[JustPlaneChris]

Remember, if force hasn't worked then sufficient force has not yet been applied.