Light Machine Corp. Benchman XTr (retrofit)

Nice forum!
Looks like 5000rpm spindle motor died on my machine. Does anyone know what is the procedure to remove pneumatic draw-bar ? It seems like it needs to be removed in order to get to the screws for motor mounting plate.

Regards!

Can't really help you much. I called Intelitek and one of the support guys there had a drawing from a newer machine I think. This one uses a standard collet, not the quick change ones that the Tool Changer uses, but it looks similar so might give a clue on what to do. It does look like you may have to disassemble the power draw bar to get the drive pulley off. Hope this helps

Steve

Hmmm, maybe this IS how it works..... Please tell us what you find out!

Anyone currently cutting metal or have speed and feed information? I have my Benchman running and trying to see what it can do. I have been testing with a .25 end mill and I decided to try a .5 end mill. There is a lot of conflicting information. Most the information sites say that the end mill can operate at about 800 sfm on Aluminum. The lone exception is Little Machines which give 165 sfm. Based on what I have seen, this seems more reasonable and I thought it was just a matter of these being small mills. I did the calculations and get a feed of 10 IPM and spindle of 1261RPM with a pass depth of .125" (.5 should be able to go up to 1/2 it's diameter) this causes each flute to cut .004" per revolution. This worked but I felt like I was on the limit of the ability of the machine. It was noisy and squealed a bit. I thought I could increase the spindle a little and see what it did. The spindle overloaded and shut down at 11IPM.
I have not managed to find a copy of the Allen Bradley DDM motor driver so I'm not sure if the overload is something programmed in the controller. I thought it would make sense to ask if anyone else had any insights. Thanks in advance.

Let me start off by saying I am not an ET and have limited electrical skills but am responsible for other maintenance functions at our shop. We have 3 Benchman XT w/45k spindles and ATC. All was well until about 6 months ago when we had one machine stop moving with the door locked and in the tool change position. Finally able to get the door unlocked but spindle will not energize and table will not traverse and Z axis will not move.
Intelitek made a new power supply and a couple repairs on the main board but still have the same problem. When we start the machine
1) There is a S-Enc red error flashing in the lower LH of the screen. Tech said he “ thought” this was spindle encoder error but machine does not have a spindle encoder.
2) The spindle will not energize and will go through the warm up cycle without turning. We eventually get “ Timed out waiting for the spindle to reach 15000 RPM Sensor indicated RPM is 0. Is the spindle at a safe speed to operate” Y..N
3) After responding yes and attempting to move any axis we get “ Amps could not be enabled, please try again. If problem persists, contact tech support ( FUNNY cause it DOES NOT EXIST)

Any thoughts, ideas, tests that you guys have would be a great help prior to a full retro. Not sure what our problem may be but think is could be something simple.
Thanks
TG

TGTROPIC, If you have a TL series spindle motor, the encoder is built in. Mine is a 5K but there has to be some kind of encoder for the unit to even know it has a spindle error. That is a symptom though, not the problem. If I understand right, the 45K system has a warm up routine and checks speed. Since the measured speed does not match the expected speed you get the fault. The real issue is that the spindle is not turning at all. Unfortunately, I can't really help you with what to do. My unit has an Allen Bradly Ultra 100 controller that runs the spindle motor. I think what ever controls yours is somewhere in the top of the unit. If it were my unit, I think the problem would be in 1 of three places. 1) a bad spindle motor. You can probably ohm out the coils. 2) a bad controller, like I said, mine is an Allen Bradley Ultra, if you have one of those in the top, I think you can talk to it with a program that should be on your computer that is separate from your normal operating program. I don't have it but it's called something like Ultra Master for my unit. 3) The controller card that sends speed signals is defective and not commanding your spindle to turn.

TGTROPIC wrote:

1) There is a S-Enc red error flashing in the lower LH of the screen. Tech said he “ thought” this was spindle encoder error but machine does not have a spindle encoder.

Your machine does have a spindle encoder, and that is likely the source of the problem.Attached is a pic of the spare 45K spindle that I got with my machine. The encoder is contained in the upper portion of the housing.



It has been rebuilt by a company in OK. I will get the contact info for you later today. They may have a testing procedure for the encoder.

OOPS! Just had an insight.. There is a small power supply on the left hand side as you face the unit from the back that might supply power to the main control board. You mentioned there was a power supply replaced, was this the one?
In addition to that supply there is a 24DCV supply. The door lock, pneumatic controls and spindle control on my machine all use 24VDC that came from the Lambda power supply. The Servo Amplifiers use a 10V signal but I am unsure where that comes from but might also be supplied from the 24V supply. The supply has a white connector with two purple wires, a red wire and then three yellow wires. It also has a fuse on the upper right of the board.
You mentioned not being an ET so I'm not sure of your skills but if you feel confident, the first thing I would do is: unplug the 240vac and check the fuse and if it is good, plug the 240vac back in, power the unit up and check for 24V between one of the Purple wires (+) and one of the Yellow(-). This is an easy test and I suggest you do this before you mess with anything else.

Spindle is bi directional TDM brand. Spindle Driver controller is a Safetronics VG05 JVOP-130. I have a back up Safetronicst that has been rebuilt and we have swapped these to no avail.
you are correct on the warm up cycle.

We have had spindles rebuilt a couple of times by GTI in NH. after checking, they say my spindle doesn't have an encoder.
there is a Safetroncs drive unit that possible take care of that?

correct on the power supply replacement. this goes in place of the old PS with a donut xformer also removed.
voltage on all purple to yellow checks just under 24v dc.