Spindle Orientation

buschbwbusch

buschbwbusch
Does anyone have a line on getting spindle orientation to work with a VFD of any kind. Mysteriously throughout the web I cannot find a decent reference of any kind on how to accomplish this task...or even a hint of what VFD to use in order to get this kind of option out of one. You would think it wouldn't be so hard to find..it could be I'm just not good at finding it, but usually after hours of scanning the interweb I am able to find a manual for something that points me in the right direction.
 

masso-support

MASSO Support
Staff member
Most of the time the spindle is oriented by using a servo motor because it has an encoder connected and can be stopped at any angle. In case of a VFD, feedback is an issue because there is no feedback going to the VFD.

Now this can either be done:
  1. By connecting an encoder to MASSO and MASSO then tries to lock the spindle in position by controlling the VFD.
  2. Or have the spindle move at very very low RPM with nearly no torque and then stop it in position using a mechanical stop.
 

buschbwbusch

buschbwbusch
Ok these are the options I was hoping for. I am guessing I can use the z pulse on the encoder and an output to drive a mechanical clamp spindle in right location. Is there much of a use for the A and B phase on the spindle encoder? In thinking about how it would work would it go through a macro where it was waiting for a z pulse and then counting pulses... that count could be a variable that would let the end user define the final location of where the actual orientation would be.
 

gmarsh1

gmarsh1
Very interested in this topic .. I would like to add an automatic tool changer to my machine, but with BT30 tooling spindle orientation is a must.
 

masso-support

MASSO Support
Staff member
I think the best would be if we add this to the M05 logic, every time we stop the spindle for a tool change, we take data from the encoder and stop the spindle in position. Also its good to check with the encoder data as if the spindle is not in position then we can alarm out and stop the tool change.
 

buschbwbusch

buschbwbusch
What it the next step then. Do you have an encoder you would recommend...or one you know of the works well with masso in this way?
 

gmarsh1

gmarsh1
There are several cheaper encoders available from china (Search Amazon) .. I have messed with a few of them and have discovered the biggest drawback with most of them is the rpm's their rated for .. My mill has a 7200 RPM top speed with motor to spindle at 1:1 ratio .. I've not been able to locate a 'reasonably priced' encoder that is rated for that much rpm. I wound up with a 'Hollow Shaft' encoder made for an 8mm shaft which is rated up to 6000 rpm, so I decided to give it a try & see how long it lasts. The hollow shaft allows the encoder to take up much less space at the top of the motor.

I disassembled my 3hp 56C TEFC motor and turned the top portion of the armature shaft down to 8mm (where the plastic fan used to press on) after mounting the encoder, I made some small spacers to re-mount the fan shroud (about 6-7mm higher than stock) Then I added a large 100mm - 110v fan on top of that for cooling .. That actually cools the motor MUCH BETTER than the stock fan because when the motor is running at low rpm the elect. fan is still blowing at full force. I'll just have to see how well the encoder holds up .. My reason for wanting an encoder is to monitor actual rpm vs called for rpm. To hopefully have the rigid tapping feature from the lathe controller brought over to the mill controller. And for spindle orientation to allow for an automatic tool changer as well.
 

masso-support

MASSO Support
Staff member
First we need an encoder for those RPM ranges and secondly this is something we have to add to the software logic and work on.
 

buschbwbusch

buschbwbusch
Do u think an npn encoder is best. I found a 5-26v 6k rpm one on amazon. Btw i am partially doing this on a forum to finally make a path for others to follow. If anyone else is interested in this topic please post here in order to lay the bread crumbs
 

buschbwbusch

buschbwbusch
I understand Masso is crazy busy in development of many thingz. Just curious about what kind of time frame there would be on developing this. I would think this as akin to rigid tapping and lathe threading.
 

buschbwbusch

buschbwbusch
Don t let this topic die...it is requisite for big boy machines. If Masso pulls it off well it is huge along with rigid tapping and lathe threading. Btw peck tapping is baller. Milltronics does this and we are able to do 0-80 threads deep no problem.
 

arin-chang

Arin Chang
Yes I would love to see if you can get this to work. Especially for those with the BT30 spindle for tool changing purposes. This along with Rigid tapping would be next level.
 

MaccaRnD

MaccaRnD
Is there any update on spindle orientation, has anyone had any success, my whole Cnc build is on hold atm trying to sort out a reliable method to orient, I want to buy another Masso but want to know if it will work as intended, will something like a Delta C2000 plus work with masso and spindle orient, I have a BT40 9000rpm 11KW spindle I need to be able to orient.
 

gmarsh1

gmarsh1
Last input on this topic from Masso is post #11 from 2018 ..

Has there been no further progress on this feature, or can it be found somewhere else on this forum?
 

zombieengineer

ZombieEngineer
@gmarsh1 - Have you considered thread milling?

To have a system that can perform rigid tapping is "challenging" - specifically the spindle rotary encoder requires sufficient resolution. I haven't crunched the numbers but gut feeling is that a high resolution rotary encoder (back of the envelope calculations suggest >100 counts/rev for a 1 mm pitch thread).

Back to thread milling (from the NYC CNC link):
  • You can adjust the tolerance of the thread to your desired fit
  • It s better for hard materials, it allows you to cut material in progressive passes
  • Unlike taps, thread mills won t get stuck in parts if they break, and often won t even damage the part
  • You can cut countless thread sizes with a single tool
  • Thread milling allows cutting odd sized threads
  • You can also use a thread mill to back chamfer the hole
  • Thread milling requires much less horsepower from the machine than tapping
  • Threadmills are readily available in carbide, as opposed to most taps being HSS or powdered metal

I am using a single point thread mill to cut a 3/4" 16TPI internal thread using a Sherline mill (the spindle motor is only rated for 60W)
 

gmarsh1

gmarsh1
Yes, I agree thread milling is the way to go ..

But I need spindle orientation to run an umbrella style BT30 tool changer ..

According to their last post, it could be added to the M05 logic.
 

MaccaRnD

MaccaRnD
Over the last few months I have contacted by phone and email somewhere between 20-30 different companies in Australia and a handful around the world in regards to spindle orientation and a drive capable of doing it. The best I have been able to come up with is a Yaskawa A1000 drive with a PG card (pulse generator) installed and orient software. ive read through their manual quite a few times and from what I can gather it seems to be a relatively simple process (guaranteed I just stuck my foot in my mouth and it will come back to bite me).

With This drive it should be able to except the 1-10v from a Masso for speed control, mand the forward and rev signals to change direction as a normal VFD does. However if you wire in an Encoder to the pulse generator card on the VFD (their are a few different card options depending on spindle set up and use (belt drive/ gear drive /different ratios) pick which suits the application best) and on the PG card you can also wire in an output from Masso to trigger it. So if you can set an output to turn on when a tool change is called for it to orient (M19) that signal will get to the pulse generator and the VFD will essentially disconnect control from Masso 1-10V and the PG will take over, and follow a sequence that you set in its parameters, it will slow down to a specified speed and rotate the spindle until the PG card gets the signal from the encoder its in position and then the Spindle servo will electrically hold that position. and allow you to do the tool change. then when the signal is cut (ie after tool change ) the VFD will revert back to normal Masso 1-10V control. So Im looking at retro fitting the low pulse count Masso optical encoder direct to my spindle for rigid tapping and replacing the other encoder with a High pulse count for the PG card to orient off, as its not effected by the low Htz encoder that Masso can compute with.

Well I really hope that is how it can work because I just spent $4800 on the drive. while the Drive tech I was dealing with was rather good at getting back to my emails he didn't know about drives being able to be turned down to output a lower voltage, and nilly had me convinced that I needed to buy a step down Three phase transformer to reduce my wall power to 240v for their 240 v drive. After some research of my own and questioning. I got him to look into my qestion and Now I have the 415v model getting built for me. I should have the Drive by the end of Dec fingers crossed.

This is to the best of my understanding of it all, I encourage research into it, and if I'm wrong please tell me where and how.

Is their a way to PM people directly on this Forum rather than only group messages

Here's the Orient part of the Yaskawa Manual

 

breezy

Arie
Staff member
Mac,

From documentation for the Umbrella TC
  1. If spindle indexing is required and "Tool Changer - Input 6 (Spindle in INDEX position)" is assigned to one of the MASSO inputs then:
  2. Tool Changer - Output 4 goes HIGH for VFD to Start JOGGING the spindle at a very low RPM.
  3. Tool Changer - Output 5 goes HIGH for VFD to Automatically stop and lock in INDEX position.
  4. The system waits for the "Tool Changer - Input 6 (Spindle in INDEX position)" to go HIGH.

So it is possible to index the spindle without using external M commands.

Regards,

Arie.
 

zombieengineer

ZombieEngineer
I should of read the entire thread before posting...

I am currently looking through VFD driver manuals to determine which combinations support position:
  • Bosch Rexroth VFD does not support spindle position/homing (no control over jog speed)
  • Delta C200 does not support spindle position/homing but does support "jogging" at a defined speed
  • Delta C3000 appears to support spindle position/homing using multi-function input
  • Delta MS300 appears to support spindle position/homing using multi-function input
  • Delta VFD-M appears to support spindle position/homing using multi-function input
  • Hitachi NE-S1 does not support spindle position/homing but does support "jogging" at a defined speed
  • Yuhuan Huanyang HY series does not support spindle position/homing

The VFD drives listed as supporting "jogging at a defined speed" would require a board to pick off the index and position pulses. This assumes that once jogging is released the spindle stops moving due to friction.
 
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