Matsuura spindle motor/gear box

Its a 1987 8000V,vertical 7.5 HP.
For a couple months now at T/C she has had trouble with spindle locking for proper position ( lining up for T/C arm to grab tool)she would osilate back and forth (i would grab it to stop this, tools would change).

then i discovered that if she was in low range, no quiver!!! cool, right?
just shift to low range(she's a 2 sp.)before T/C, so all was ok.but no...
I was using her as a lathe, small chuck in spindle, lathe tool clamped in vice
had set all my XYZ zeros, oh shit! lathe tool wants spindle to run C.Clockwise.
no problem,M04, good to go, run 34 parts, now when spindle stops or starts she clunks, M59(tool clamp) she osilates way bad, big red button got hit when I tried that!

So thats the front story to my question, I think there is some type of lovejoy like connector between the motor and the gear box that has failed ?
and I think my running her C.clockwise finished off this"lovejoy"

what do you folks think?
thanks for listening.
Gw

Greg White said:

For a couple months now at T/C she has had trouble with spindle locking for proper position ( lining up for T/C arm to grab tool)she would osilate back and forth (i would grab it to stop this, tools would change).

Click to expand...

Turret on an Eagle 2000, exact same behavior right down to grabbing it to stop the quivering, cause was slop in the mechanical drive to the turret, similar to what you are saying.

Seems real likely that you are right.

Sounds like you have magnetic sensing type spindle orientation. Fanuc or Yasnac? There are adjustments on the spindle drive that can affect improve the orientation behavior. If you have a mechanical problem you should fix that first before trying to adjust anything on the drive.

One thing that I have found to cause bizarre orientation problems, is a broken magnet. A magnet is mounted to the spindle shaft with the poles perpendicular to the spindle axis. The orientation sensor uses the polarity of the magnet and its effect on the windings inside the sensor to determine where the orientation "balance" point is. With a broken magnet, the magnetic field is disrupted and the sensor can't effectively find that "balance" point and the spindle drive "hunts" for it by switching the direction back and forth.

A broken magnet will drive you f'n nuts trying to figure it out.

The adjustments on a Fanuc spindle drive of your era which effect the orientation will be the gain adjustments. There are separate gain settings for high and low gears. Check the magnet first before going to far.

The manuals for your drive should be free to download on the internet.

thanks guys, pulled the sheet metal yesterday, looks like the flex coupler between the spindle motor (I was calling it lovejoy like)has been destroyed ,at least the material that flexs is . good thing the material is red, its everywhere except where it should be, its in quite a few pieces, made it easy to spot.
I will pull the motor today.
Its a Yasnac, dont recall motor brand. oh, another thing,its a model 800V,not 8000V.
will update, probably Tuesday. thanks for commenting.
Gw

Ok, so,ordered part from Matsuura,3 weeks, $183.66.
Good deal for 30 years old. I feel blessed.
Only thing is ,i gotta run the lagun knee mil now.
thats all folks.

looks like you already figured it out, just read the post title and was going to say the spider coupler is bad, they go all the time on the matsuuras. I would order a spare, if you need it quicker I would check with methods machine they are no longer a matsuura dealer but they have a lot of old inventory.

thanks oldmansimek,do you folks think i can just replace this flex spider and be up and running? will mach loose its spindle orintation for T/C? do i need to NOT rotate motor when i hoist it?
Gw

Greg White said:

thanks oldmansimek,do you folks think i can just replace this flex spider and be up and running? will mach loose its spindle orintation for T/C? do i need to NOT rotate motor when i hoist it?
Gw

Click to expand...

Since it has a geared head, the "reader" hast'ta be on the spindle it'self, and not rely on the motor encoder.


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Think Snow Eh!
Ox

Thanks Ox, thanks a bunch.
So I haven't pulled motor off head yet,it (motor)seems to be incased(bolted on)with sheet metal to aid with the cooling, i pulled the screen on the very top to clean it, dropped one of the screen retaining screws(phillps head)between sheet metal and motor, should I pull motor and remove sheet metal find screw and clean motor? or leave well enough alone? Is the motor totally inclosed so as screw cant get inside? I do have time on my side.
Gw

It's highly unlikely that they would use an open frame motor. But, I'd still want to get the screw out of there.

so I got the flex coupler from brown truck yesterday, the 1987 Matsuura is up and running again.The Lagunmatic is cleaned and put to rest again.
Thanks for the words men.
Gw