Is it possible to use a servo as a milling spindle and synchronize the speed with the Z-axis so that you can cut threads?
Für CNC-Milling Machine, not Lathe.
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Is it possible to use a servo as a milling spindle and synchronize the speed with the Z-axis so that you can cut threads?
Für CNC-Milling Machine, not Lathe.
I have servo motor for spindle on my new machine.
It is speed controlled, not positionally. Driver has an option for encoder output. I use it for synchronization.
I will have more info about how I did it in future weeks when I get more used to machine.
Hi,
I have a servo as spindle motor and I can have it synchronize to do rigid tapping, I use Mach4 however, I dont know whether your
control system can do it.
Craig
Yes it's possible to use a servo motor for a spindle motor. But this is not needed for rigid tapping.Quote:
Originally Posted by tantemay
To synchronize the spindle to the Z axis only requires an encoder, or in some cases, only a once per rotation sensor on the spindle.
Doing this requires that your control will support the encoder or sensor input and that your software has rigid tapping available.
With "only once per rotation" controller does not receive enough information about spindle to do reliable rigid tapping. Flexible collet is a must.
With encoder rigid tapping works fine. Some servo drivers have encoder output which can be used and works great. Like I said, I have servo motor on my new machine and I'm using it as normal spindle.
Please, can you explain the connection - point to point - between the servo motor driver (step/dir input, maybe) and MK3 controller, and setting on TNG?
First thing to consider using a drive with step dir signal as spindle is to understand that mk3 does not use any acceleration on the frequency signal for spindle. so the used servo controller has to handle that. If the servo controller is a stupid one, it will result in error due to high acceleration and position follow errors. The drive needs an option to set own acceleration and to allow high step differences between step signal and actual position. Not all servo drives can be configured that way.
To connect a servo drive as spindle, connect the dir signal from servo drive to the output of the mk3 you have selected as ccw in spindle settings.
Connect step signal from drive to the output you selected as speed output in spindle settings. Must be one of the pwm capable outputs.
Then set spindle speed signal to Frequency and set the desired values.
Synchronisation is not required by feedback of encoder in that case, because the spindle will rotate at exact speed So you can set the syncing to the optio "as set" in settings.
Some servo drivers also have "virtual encoder" which you can use for spindle synchronization. Works great on my machines..
Ok. Thank you!
hello this is a diagram of the connection of the servo controller which pins (numbers) have to be connected to the MK3Quote:
Originally Posted by PlanetCNC
Quote:
Originally Posted by Macwolf
I have a board with line drivers and high speed optos built into it for direct connection to incremental encoders.
I'm not entirely sure on the feedback wiring either and docs are generally a bit vague.
From all the reading of various manuals etc,
Does this wiring diagram below look about right?.
Hopefully planet cnc comes back with response.
I've used lpt input based port, inputs 9 to 12.
I would use our new OptoIsoCtrl3/4 PNP board. It is designed exactly for this.
It is a new product which will be available in shop in few days.
It is designed for Mk3/4 controller but it also works with Mk3. Mk3 version will have 10pin connector, this one has screw type.
connecting the driver outputs was simply connecting the + pins to the board and the GND. already I don't need a rotary encoder
Quote:
Originally Posted by PlanetCNC
That is just for limit switches and the like. Is nowhere near fast enough for use in the encoder erea of a drive.
This design isn't new, it's standard, you can get very similar 4 channel ones at 1/3 the price.
Try again.
Need a HIGH SPEED line driver type option for:
OA,OA-
OB,OB-
OZ,OZ-
OCZ,GND
Encoder feedback / indexing.
I meant this:
https://planet-cnc.com/wp-content/up...toCtrl34_2.pdf
See diagram for PNP version of adapter -> Encoder with Line driver output connection
https://planet-cnc.com/product/optoctrl-3-4-board/
I believe this should be suitable for your application.
OptoIsoCtrl3/4 PNP board.can handle 10MBd. I'm sure this is fast enough :-)