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MV-40 Z axis adjustment

eaw99517

Plastic
Joined
Jan 26, 2012
Location
Eastern Washinton State
Hello, we have a new to us used MV-40 with a Yasnac MX3 controller that was recently purchased. It was originally set up with BT-40 tooling. The shop is set up for CAT40 tooling. We purchased new CAT40 grippers on the end of the tool changer arm and installed them without any major issues.

I then checked the alignment of the tool changer gripper with a tool in the spindle. To do this, I homed the Z Axis, and manually rotating the tool arm around so that it was in position to grab a tool that was in the spindle. I noticed that the tool in the spindle was about .120 too high. I went to Parameter #6306 and dropped the Z Axis Home Position down by .120, powered the machine off and re-homed the Z Axis. I rechecked the alignment of the tool arm gripper with the tool in the spindle and it looked perfect. I then manually lowered a tool in the tool pot on the tool carrousel using the buttons on the control panel and the alignment also looked perfect.

I then noticed that we had an alarm. It was error 263 which according to the manual is "ER PULSE AT C PHASE LATCH". I hit the reset and the error cleared. I set the machine up for automatic operation and was successfully able to execute a tool change in MDI mode. I then ran a program in the machine and it ran perfectly with tool changes etc. no errors.

I then re-homed the Z axis again and the error (263) popped up again. I did some messing around with the values in Parameter #6306 and discovered that if I raised the Z Axis Home Position up by .016, the error did not occur. Of course, when I did this, the tool arm gripper was not perfectly aligned with the tool in the spindle.

It doesn't appear that the 263 error is a show stopper, but obviously I'm missing something here, and I think...hope that the solution is a simple one. I thought about adjusting the Z Axis home position tab down so that the mechanical home position switch is triggered sooner when tha Z axis is returning to the Home Position but not sure if that's a wise idea.

Anyone have any ideas on this problem,
 
So there is another way to align the arm, i'm pretty sure the tool changer is the same as on an MVJR. The arm is attached to the tool changer mechanism shaft by a tapered lock collar that is drawn up with bolts under the cover on the bottom of the arm. It is possible to loosen the collar and move the arm up ddown on the shaft to position it slightly. This is normally done to position the arm ends to the spindle, but it will also allow you some up and down adjustment. Do you have a parts book for your machine? Look at the tool changer assembly where the arm attaches to the vertical shaft. Good luck. Probably best to be able to adjust the home position, but I'm just throwing this out there.
 
Yes I thought about adjusting the tool changer arm. Unfortunately, in order to get the arm re-positioned after you loosen the bolts so that the CAT40 tool is accurately centered in the spindle bore before it is inserted into the spindle, you need a special alignment tool. It costs any where from $1000 to $1400. Naturally I dont think the boss will spring for that.

I think that if I can't find a solution by make parameter changes I might try the following:

1. Adjust the Home position tab that triggers the micro switch for the Z Axis. Fairly simple to do and not complicated. If that doesn't work, I'll go to something a bit more complicated.

1. Home the Z Axis, and power the machine off.
2. Use our overhead gantry crane and support the Z Axis/spindle assy. It weighs approx. 1500lbs.
3. Remove the Z Axis belt and Z Axis brake taking care not to move the shaft on the Z Axis motor so the encoder stays in the same position.
4. Drop the whole spindle assy. down approx .120 using the overhead crane.
5. Re-attach the Z Axis belt and brake.
6. Power the machine up and re-home the Z Axis. My hope is that I will have to adjust the Z Axis Home Position Parameter in the Positive direction (UP) to get it aligned with the tool changer arm. In theory, this might put the Z Axis Home Parameter values somewhere in the neighborhood of where they were originally set. The original issue was that I had to adjust the Z Axis Home Position Parameter in the negative direction (DOWN) to get the tool changer arm aligned with the spindle. This caused the 263 error.

Or maybe I don't know what I'm doing and neither solution will work....LOL!
 
Every vertical I have ever bought has had a fucked up toolchanger arm. Bent or locks not working or mis-adjusted, etc.

Nobody uses that stupid tool. What are you going to do? remove the entire magazine and shim it to adjust the centerline? No, the slop in the toolchanger compensates just fine.

Start with what you cannot change- take the arm off, clean it up, straighten it out and align it to a tool in a pot. Then adjust Z.
 
The arm itself seems to be fine. Well as far as I can tell.....it seems to be fine. All I am doing is switching the tool holders on the end of the tool changer arm from BT40 to CAT40. It was changing the BT40 tools without any issues. After I installed the CAT40 tool grippers, I did adjust the Z Axis Home Position Parameter -.120 to get the CAT40 tool gripper lined up with a CAT40 tool in the spindle. It changes the the CAT40 tools just fine. The problem is that I get a 263 Z axis parameter error when I home the Z axis when I first power the machine on. The machine runs fine after I press "reset" to clear the error. The Z axis home position is lined up correctly for the tool change, so the machine is actually moving the Z axis to the value that I entered into the Parameter, but for some reason it does not like it.

I was hesitant to do anything with the tool changing arm because it's lined up perfectly on the Z Axis with the pot in the tool carrousel. I was anticipating a Z Axis adjusment afetr the tool gripper change, but I was hoping that it would be something like a .020 or .030 adjustment. Not .120. I'll definately take a closer look at the arm itself and see if that is a better approach. I've had to change the tool arm in another identical machine, so I'm familiar with that process.

Thanks for the suggestion.
 








 
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