Flex Shaft Vibrating

[mtylerfl]

Hello,

Just added another machine to our arsenal this morning.

Did a test carve when I noticed that the RMP's seemed to fluctuate ever so slightly and saw a tiny amount of "oily splatters" on the board's surface about 2% into the carve. Stopped, scratched my head, then resumed the carve.

I then observed the flexshaft would vibrate rather violently whenever the Y truck moved nearer to the keypad side of the machine. The RPM's and flexshaft 'smoothed out' as the Y truck moved away from the keypad side. I also noticed the flexshaft was getting quite a bit warmer than what I consider normal based on my previous experience.

Stopped the machine, called LHR. The tech suggested that the flexshaft might be overlubricated and told me to remove it, wipe it down, replace and see if that fixed it. But it didn't.

Then he suggested I swap the flexshaft with another machine to see if that helped. Same problem, unfortunately.

Then he told me to remove the flexshaft and bit, then peer down through the top hole in the Z Truck while spinning the chuck. If the square hole made a nice, neat 'circle' while spinning fast, then all was well with the square shaft receptacle. If it appeared to have an 'oval' shape while spinning, then the square was, well, out of square. That might account for the vibration. I did what he said and the square seems fine.

While I'm waiting for a call-back I thought I would ask if anyone else has experienced a similar problem with the flexshaft? It only 'vibrates' when the Y truck nears the keypad side. Weird.

[liquidguitars]

I had the same thing when clime cutting a guitar top last week. I needed to replace the cut motor CCM and flex shaft core, my replaced flex shaft plastic outside is a little softer than my old one??? the chatter is less now after the replacment parts.

LG

[rjustice]

I dont have the problem, but i have an idea...

How does the cable fit into the "top hat" on top of the spindle?.... if you apply pressure side to side v/s front to back, do you notice a looseness in one direction?... If so, perhaps that when the truck gets towards the keypad, the loosenes is causing the cable to slightly misalign with the square hole in the spindle. I believe this would allow it to do what you are describing...

Good luck

Ron

[mtylerfl]

I dont have the problem, but i have an idea...

How does the cable fit into the "top hat" on top of the spindle?.... if you apply pressure side to side v/s front to back, do you notice a looseness in one direction?... If so, perhaps that when the truck gets towards the keypad, the loosenes is causing the cable to slightly misalign with the square hole in the spindle. I believe this would allow it to do what you are describing...

Good luck

Ron

Thanks LG and Ron for your comments and ideas.

Ron, I don't notice any play or looseness in the flexshaft when inserted in the top-hat.

I think the LHR tech had me do the "spin" test while peering down through the square hole for the reason you suggested - to see if the square hole was out of square which might lead to the vibration and chatter of the cable.

Didn't get a callback today, so I'll see if I can get ahold of someone at LHR tomorrow.

LG, I'll mention what you said and see if they think I may need to have any of the parts replaced as you did.

[rjustice]

One other thought.... If you grasp the z-truck when it is towards the keypad, can you twist it, or tilt it in either direction?.... maybe the rails are loose on that end of "Y" travel....

Ron

[mtylerfl]

One other thought.... If you grasp the z-truck when it is towards the keypad, can you twist it, or tilt it in either direction?.... maybe the rails are loose on that end of "Y" travel....

Ron

Hi Ron,

I tried what you suggested, and there is no play in the z-truck at all. Thanks for the idea though - please let me know if you think of anything else to try or check.