View Full Version : Trex 250 tracking and alignmet with HK Bladegrip Bearings 682x

10-13-2011, 07:57 PM
Hi Guys,

I am reposting this from ArcHeli as I have not had any response on this.

After my recent failure to use idle up when inverting : ( , I have rebuilt this little heli.

I have used HK 682x bearings in the blade grips and have noticed movement in the feathing shaft, which will put the tracking out I think.

After assembling, I turned the feathing shaft with a hex driver to make sure that the feathering shaft was rotating true. I then noticed movement at the other end, but the thing is that the feathering shaft is brand new.

I then replaced the shaft and re assembled only to find the movement in the bladegrips was still there when rotating the feathering shaft.

I think I have pinned it down to the HK bearings I have used. These are brand new and seem to have play in the centre. A bit hard to describe, but putting a bearing on the feathering shaft and checking for lateral play shows quite a substantial amount of movement.

Is this right?
Are the Align bearings any better?
For sure this is leading to tracking issues and hover stability?

BTW my tracking is almost spot on and only changes when adding more throttle / pitch.

Thanks for any suggestions.


10-13-2011, 08:18 PM
best thing to do is get her in the air see hoe she dose it coudl be a bit lose bc there not under load you align bearing work wel too but theres no harm in trying just make there nothing lose

10-14-2011, 01:06 PM
try replacing the bolts that hold on the grips! might be bent!

if not could be the blades! I just had ta change out some FG blades ta carbon cuase I couldn't get them ta track! now with the CF blades, tracking is spot on!:banana

10-14-2011, 02:32 PM

I'll check them.

10-14-2011, 05:52 PM
I have a friend with a HK 250. The bearings are pretty crappy--and this opinion is from a guy that revels in cheap!

Do yourself a favor, get some at least "ok" bearings and replace any bearings that are under load. Main and tail grips as well as main rotor come to mind.

10-17-2011, 02:30 PM
I was looking for bearings a little better than the align. I found a company here is Oz, but they wanted $12.00 each bearing :thumbdown: