Starturn 4 conversion

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automata
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Starturn 4 conversion

Post by automata » Fri 17 Feb , 2012 0:41 am

Hi all,

Sorry if this has been answered before, but I am trying to convert a Starturn 4 to EMC2 control as quickly as possible. I haven't got great electrical know-how so I'm not sure exactly what to do, and I think wiring a new breakout board/tracing wires from the existing electronics is beyond my skill and patience.

Here are my ideas, please give me any feedback you may have:

Is it possible to simply switch out the DB-9 to a DB-25 to connect to PC and use modern software? Something like this: http://www.cnc4pc.com/Store/osc/popup_image.php?pID=204

Or would it be possible to discard the old electronics and put a new driver board in? I am looking at this board with a relay for the spindle control: http://www.easy-cnc.com/3axisdriver.html

Are either of these solutions feasible?

Thanks

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Re: Starturn 4 conversion

Post by Denford Admin » Fri 17 Feb , 2012 10:34 am

Is it possible to simply switch out the DB-9 to a DB-25 to connect to PC and use modern software? Something like this: http://www.cnc4pc.com/Store/osc/popup_image.php?pID=204
I'm not really sure what you mean - the only connectors currently on the Starturn would be for RS232 communication so a DOS program could send (drip feed) CNC programs to it. It wouldn't be practical for any software to control the machine via that connector.

Or would it be possible to discard the old electronics and put a new driver board in? I am looking at this board with a relay for the spindle control: http://www.easy-cnc.com/3axisdriver.html
This is more like what you will need to do! If it has a 0-10V analogue output as well, then you will be able to control the spindle speed. Just read up on the spindle drive you have to see if it requires an isolated analogue because the 10v input may not be relative to ground (ie, you could blow up the output on your new controller card)
It'd be handy to get a 3 axis card instead of 2, in case of failure or for a stepper driven toolchanger etc...

automata
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Re: Starturn 4 conversion

Post by automata » Fri 17 Feb , 2012 17:10 pm

Thanks for that info, Admin.

What I meant with my first query was replace the DB-9 socket with a DB-25 socket. I've found that currently the DB-9 (on the rear of the machine, to interface with a computer) plugs into a A16-LPH 26 pin socket on the board and could be easily replaced with the same part except in the DB-25 variety. Would this work?

Hmm, I'm not to sure about the spindle drive needing an analog isolator. Couldn't find any info on the net about this motor. Some info I found on the motor itself:

Small Electric Motor Ltd.
SN: E4162
Perm. Magnet DC motor
Type DPM 30L2
Output 0.44
RPM 4000
Volts 160
Amps 3.7, not to exceed 26
K 87-70463

Controlling spindle speed via software would be nice, but not a must. It does have a potentiometer on the case to control it manually.

Thinking this relay board paired with the driver above would be enough to run this machine properly? http://www.easy-cnc.com/relayboard.html

I also have the ATC, I'm assuming it would be run through the extra step driver. Or would it be through the relay?

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Re: Starturn 4 conversion

Post by Denford Admin » Fri 17 Feb , 2012 17:29 pm

The relay board should control the spindle no problem if the drive has a run or enable input although I think some were turned on by switching the supply to them - in that case you'd need to check the voltage and current capability of the relay contacts. I'm think there is a relay board in the Starturn with two fairly big, 10amp relays on it.

The ATC runs the motor in fwd, reverse(24V DC) and hold in reverse (12VDC) so you'd be better off trying to interface to the existing control relays.
You'd also need to read the toolpost position, binary inputs and have some kind of logic to tell it when to stop turning and when to reverse.

automata
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Re: Starturn 4 conversion

Post by automata » Fri 17 Feb , 2012 17:41 pm

Thanks again, looks like the relay should be fine to run the spindle. From the manufacturer's website: "Every relay can close electrical circuits at 125VAC@15A or 250VAC@10A as maximum"

automata
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Re: Starturn 4 conversion

Post by automata » Fri 17 Feb , 2012 18:13 pm

Come to think of it, would it just be easier/quicker to replace the breakout board with a DB-25 interface? It has those two SD2 drivers already, just need a way to interface with them I suppose? Has anyone done this before?

This is the breakout board I am considering if this method is feasible:
http://www.cnc4pc.com/Store/osc/product ... cts_id=161

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Re: Starturn 4 conversion

Post by Denford Admin » Mon 20 Feb , 2012 9:54 am

That looks like it would be ideal espescially as it has opto-isolated analogue:
Built-in Variable Speed Control. It has an optoisolated analog 0-10VDC output that will convert a step signal into an analog signal that can be used to command a commercial VFD. This analog can be adjusted using on-board pot, so this board can be adjusted to other voltages.
It would be much easier to keep everything as it is (transformers, wiring etc..) and just add your own step+direction signals.
The SD2 manuals are here
viewtopic.php?t=561
and am sure if you searched the forum, someone has interfaced to them before

automata
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Re: Starturn 4 conversion

Post by automata » Tue 21 Feb , 2012 0:00 am

Hi Admin, thanks for all your help. I will try to interface with the new breakout board.

The thought is still lingering though, is it possible to just connect a new ribbon cable with more pins than the existing one? You can see what I mean in the photo where the ribbon cable connects to a DB-9 plug and the BOB. It would certainly be the cheapest, quickest, and most simple solution. It almost seems TOO easy to be true.

Could that work? Is it worth trying?
photo.JPG
photo.JPG (162.11 KiB) Viewed 20671 times

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Re: Starturn 4 conversion

Post by Denford Admin » Tue 21 Feb , 2012 11:32 am

I think that 9way to ribbon is probably RS232 comms to the old GSM controller board.
That controller board will be useless to you once the new BOB is fitted - whatever commands or data it takes is unknown to us.

All you have to do really is find the step+direction wires to the drives and wire them to the BOB then wire the BOB up to the PC via ribbon / 25 way cable

automata
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Re: Starturn 4 conversion

Post by automata » Wed 22 Feb , 2012 23:12 pm

I ordered the CNC4PC C11 BOB and will document my trials and tribulations, posting photos as I go along. Hopefully I will have it by tomorrow and have it wired up by the beginning of next week!

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Re: Starturn 4 conversion

Post by Denford Admin » Thu 23 Feb , 2012 9:59 am

Hopefully
:wink:

I know it's a pain to document and take photos while actually doing this stuff, but any info would be appreciated.

automata
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Re: Starturn 4 conversion

Post by automata » Fri 02 Mar , 2012 5:21 am

A quick update:

So at the last minute I decided to go with the easy-cnc.com driver board and relay for the ease of rewiring things, as I'm not too skilled with that.

Sadly the steppers on the machine were dead. The X axis was missing a lead (not sure why...?) and the Z just did not work. I tried with 2 different drivers and got no response. Thankfully the spindle motor still works.

I got new motors from automationdirect.com. For the Z axis I used a 166oz stepper (that's all that would fit in the cabinet), and I used a little larger stepper for the X because there was room for it, at 276oz.

Tomorrow I hope to have the steppers, limits, and e-stop wired to the board and then deal with the relay. Eventually I will work on the spindle speed override.
Attachments
IMG_0441.jpg
I ripped out the rat's nest inside and got a fresh start. It looked like this:
IMG_0441.jpg (258.91 KiB) Viewed 20629 times
IMG_0455.jpg
...and then this! Ah, much better now!
IMG_0455.jpg (244.6 KiB) Viewed 20629 times
IMG_0461.jpg
Bolted on the X axis stepper...
IMG_0461.jpg (160.66 KiB) Viewed 20629 times
IMG_0463.jpg
then the Z axis.
IMG_0463.jpg (178.21 KiB) Viewed 20629 times

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Re: Starturn 4 conversion

Post by Denford Admin » Fri 02 Mar , 2012 10:34 am

For someone claiming to be unskilled at wiring, that 2nd photo looks pretty daunting :shock:

At the end of the day those old 'rats nests' were far too complicated IMO - too many different transformers, voltages, converters and logic boards for what is basically two steppers and a spindle motor.

automata
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Re: Starturn 4 conversion

Post by automata » Thu 15 Mar , 2012 13:11 pm

So things have been a bit slow going, but last night I got a decent amount done. I have the steppers and the Z axis home switch wired up to the Easy-CNC board. I'm running this machine with EMC, so last night I also spent a great deal of time configuring. I think I have the ball screw measurements correct (?), 10mm diameter, 2 revs/mm.

The spindle motor I'm running with a variable speed DC motor controller I found on ebay for cheap. It has a potentiometer that allows for voltage from 0-110 VDC. It runs fast, but not as fast as I'd like. I think I may flip the gear heads to achieve higher RPMs.

Next steps are to wire the e-stop and maybe wire the safety switch on the cover (I might also have a use elsewhere for the switch). I'm waiting on a small step down transformer to power the work light. I would like to add an X axis home switch as well.

I will post some photos this weekend.

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Re: Starturn 4 conversion

Post by Denford Admin » Thu 15 Mar , 2012 16:03 pm

Sounds good - its good to have photos.
I know safety switches get in the way of working efficiently, but I have to recommend you fit/keep the guards and interlocks.
My old-mans Starturn scares the life out of me when the spindle's going at full tilt (with no gaurding)

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