News:



  • March 28, 2024, 05:59:01 PM

Login with username, password and session length

Author Topic: Adapter shaft slipping - how to fix?  (Read 954 times)

Offline Dennis Toth

  • 2020 supporter
  • Trade Count: (0)
  • Admiral
  • *
  • Posts: 4209
Adapter shaft slipping - how to fix?
« on: May 07, 2022, 01:48:47 PM »
Had an issue while tightening my prop on my front mounted BADASS 2320 with 4mm shaft. As I tightened the prop I noticed the motor can was turning. The prop/spinner backplate slipped as the nut got tight. I grabbed the can and tighten down and it seemed to cinch tight but during the flight near the end there was a weird sound but the prop was tight when I checked? If it did slip what have you done to stop the slippage?

Best,   DennisT
« Last Edit: May 07, 2022, 02:51:51 PM by Dennis Toth »

Offline Tim Wescott

  • 2016 supporter
  • Trade Count: (0)
  • Admiral
  • *
  • Posts: 12804
Re: Adapter shaft slipping - how to fix?
« Reply #1 on: May 07, 2022, 02:59:37 PM »
If it's a collet style prop adapter then it's the wrong size, or it's worn (meaning: it's the wrong size now, whatever it may have been before).

Before it's tightened, it should slip onto the shaft with very little, if any, play.  If it feels loose from side to side when you slide it on, it's too big for one reason or another.
AMA 64232

The problem with electric is that once you get the smoke generator and sound system installed, the plane is too heavy.

Offline Dennis Toth

  • 2020 supporter
  • Trade Count: (0)
  • Admiral
  • *
  • Posts: 4209
Re: Adapter shaft slipping - how to fix?
« Reply #2 on: May 07, 2022, 04:39:53 PM »
The shaft goes on very snug, no play. The unit is a new Hyperon 4mm. I think the part that is slipping is the drive collar around the tapered shaft. I am checking the edges of the slots to make sure they are clean with no edges. Anything else that could do this?

Best,   DennisT

Offline Tim Wescott

  • 2016 supporter
  • Trade Count: (0)
  • Admiral
  • *
  • Posts: 12804
Re: Adapter shaft slipping - how to fix?
« Reply #3 on: May 07, 2022, 04:44:53 PM »
Nope.  Something has to not be fitting right -- I'm only just getting into electric CL, but I've been using drive collets like that for years in RC planes with virtually no problems.  (I only say "virtually" because I'm being pedantic -- put stuff on right, tighten it reasonably tight, and it'll work perfectly.  And "reasonably" tight does not mean to within an inch-pound of breaking, either.)

Does the drive collar have the same taper as the outside of the collet?  Any chance that you accidentally mixed parts from different brands?  Just a few degrees of difference in the taper wouldn't matter a bit if the two parts matched, but if they didn't (because of accidental swapping) then that'd cause a problem.
AMA 64232

The problem with electric is that once you get the smoke generator and sound system installed, the plane is too heavy.

Offline Dennis Toth

  • 2020 supporter
  • Trade Count: (0)
  • Admiral
  • *
  • Posts: 4209
Re: Adapter shaft slipping - how to fix?
« Reply #4 on: May 07, 2022, 05:23:56 PM »
The collar is brand new from Hyperon, 4mm, right from the package, no mixing of parts from other sets. I don't gorilla tighten just tighten like any prop on an IC. I will clean it with contact cleaner just to make sure there is nothing interfering. If it still slips, I will try a different unit. I also have never had this happen is over 10yr flying electrics.

Best,     DennisT

Offline Fred Underwood

  • Trade Count: (0)
  • Captain
  • *****
  • Posts: 807
Re: Adapter shaft slipping - how to fix?
« Reply #5 on: May 07, 2022, 07:30:52 PM »
If I understand correctly, you held on to the prop and when you turned the nut, the nut back through/including the rotor turned but not the prop.  Meaning, the collet was holding on the shaft but the prop was not tightening.  Some collets the I've seen had a smooth prop washer on the nut side, and not great grip on the drive side.  They don't grip well on a hard prop such carbon and some APC.  I used a 1/64 or 1/32 ply ring glued onto the back of the prop.  An option is 60 grip paper glued to the washer.  At first, I just stabilized the rotor (profile) and didn't let it turn and tightened the prop.  Once tight, I never had a problem.
Fred
352575

Offline pmackenzie

  • Pat MacKenzie
  • 24 supporter
  • Trade Count: (0)
  • Captain
  • *
  • Posts: 765
Re: Adapter shaft slipping - how to fix?
« Reply #6 on: May 07, 2022, 07:42:46 PM »
Make sure you are not running out of thread, and the prop nut is bottoming out before it gets a chance to pull the collet in.
MAAC 8177

Offline Ken Culbertson

  • 24 supporter
  • Trade Count: (0)
  • Admiral
  • *
  • Posts: 6036
Re: Adapter shaft slipping - how to fix?
« Reply #7 on: May 07, 2022, 08:30:19 PM »
Everything that is machined has tolerances.  +- something and usually it is quite small.  Sometimes you get part "A" (the Shaft) that just passed QC on the low side matched to part "B" a collet whose ID just passed on the high side, and it will be loose. I had one Cobra that was so collet adverse that I had to take off the cowl and hold the can with the set screw while I tightened the collet.  Why there is not an industry standard for the ridge pattern on the back of props and spinner backplates and thrust washers is one of life's mysteries.  That is why I like wood props!

ken
AMA 15382
If it is not broke you are not trying hard enough.
USAF 1968-1974 TAC

Offline Motorman

  • Trade Count: (0)
  • Admiral
  • ******
  • Posts: 3243
Re: Adapter shaft slipping - how to fix?
« Reply #8 on: May 07, 2022, 09:46:14 PM »
Some shafts have a large shoulder that comes through the drive washer. This can bottom out on some props so there's less pressure on the drive washer. I usually counter bore my props a little just to make sure they clear.

If you want to check the taper, draw lines with a sharpy on the taper then rub the two parts together. Wherever the ink rubs off will tell the story. They should make even contact or, more so on the big end of the taper.

Motorman 8)

Offline Dennis Toth

  • 2020 supporter
  • Trade Count: (0)
  • Admiral
  • *
  • Posts: 4209
Re: Adapter shaft slipping - how to fix?
« Reply #9 on: May 09, 2022, 07:43:11 AM »
I was able to get everything tight. I first made sure the collet had no sharp edges or ridges at the cuts. Cleaned the surfaces with contact cleaner. When I put it together, I got it snug then held the prop and motor can (just a light pressure on the motor can was all that it needed) and gave it a good tighten. No slip, prop on straight and running true. Seems some of the collets might need a little break-in the first few times they are tightened.

Best,    DennisT


Advertise Here
Tags:
 


Advertise Here