Messages

11

General Mach Discussion / Re: GEC Gemini Speed Controller - Info required

« on: May 31, 2009, 06:37:51 AM »

Melee

If you remove the link between 3 and 9 then it stops running and I can't get it to run again. All it does now is make the transformer buzz and then blow the fuse. If you start the spindle by hand then it can kind of keep it going but it is not happy! I will let the electronics lose all their charge for a bit and try again but I am not holding out much hope for it

Simon

12

General Mach Discussion / Re: GEC Gemini Speed Controller - Info required

« on: May 31, 2009, 05:02:24 AM »

I stripped everything back and started again trying your wiring and I have got it working of sorts...

1 - not connected
2 - 0-10v
3 - 9
4 - not connected
5 - not connected
6 - not connected
7 - 8 - 0v
8 - 10 - 7
9 - 3
10 - 8 - Earth

However the speed control is over a much smaller voltage than expected, I expected max speed to be at something like 8v as this is what is was origionally.
Max speed is now something like 3.5-4v I haven't actually found the max as it sounds too fast and I bottled it.

Any ideas?

Thanks
Simon

13

General Mach Discussion / Re: GEC Gemini Speed Controller - Info required

« on: May 30, 2009, 12:40:52 PM »

I am running out of 3 amp fuses fast!
However I connect it up it blows the main fuse. I know it does work as I have had it spin the motor but as soon as I switched it off, it blew the fuse again.

Thanks
Simon

14

General Mach Discussion / Re: GEC Gemini Speed Controller - Info required

« on: May 30, 2009, 08:40:16 AM »

On all my Boxford machines the motor is reversed by going through either a mechanically interlocked contactor or a relay.
Basically all it does is take the A+ and A- wires and switch them to the other way around on the motor.

P.S. n/c is "not connected" in the above, not normally closed.

I would appreciate any info on your pin 9, everything is ready to fire up the spindle on mine except I can't get the thing to move!

Thanks
Simon

15

General Mach Discussion / Re: GEC Gemini DC drive question

« on: May 30, 2009, 05:28:45 AM »

Chris,

Could you post the partial schematic please?

Thanks
Simon

16

General Mach Discussion / Re: GEC Gemini Speed Controller - Info required

« on: May 30, 2009, 05:28:04 AM »

Have you managed to get any information on the Gemini speed controller?

My machine is connected thus...

L1 = Live Also connected to Aux1
L2/N = Neutral Also connected to Aux2
A+ & A- = Motor windings

1 = n/c
2 = 0v DC
3 = 0-10v DC speed signal
4,5,6 = n/c
7,8,10 = Earth
9 = ??

Pin 9 appears to be some kind of "enable" but I don't know what to connect it to.

Thanks
Simon

17

General Mach Discussion / Re: Boxford 160 TCL - running as is?

« on: April 30, 2009, 01:08:16 PM »

Melee,

Thanks, I was just wondering if there was an eaasy way...
On my conversion I spent ages connecting all the front panel switches to a PLC and connecting it to Mach3 via ModBus.
However I too don't use the front panel so my effort was wasted.

Thanks
Simon

18

General Mach Discussion / Re: Boxford 160 TCL - running as is?

« on: April 29, 2009, 05:07:25 PM »

Melee,

Do the front panel controls still work or did you bypass/disconnect them?

Thanks
Simon

19

Show"N"Tell ( What you have made with your CNC machine.) / Re: Boxford Tooling Plate, 4th Axis & CoolJet

« on: April 18, 2009, 03:24:56 PM »

I used to make the core with a manual 4th axis but it was very laborious as you had to be at the machine all the time to turn the part between each operation.

I don't know of any bored spindles for sensible money.
I have a 2 morse taper chuck adapter which could be mounted in the same way and a conventional 3 or 4 jaw screwed on. They are quite common as most of the small rotary tables have a 2MT hole in the middle.

Simon

20

Show"N"Tell ( What you have made with your CNC machine.) / Re: Boxford Tooling Plate, 4th Axis & CoolJet

« on: April 18, 2009, 07:13:42 AM »

Daniel,

Yes the rotor core is made in one setup on the mill. The blank is turned onthe lathe to prepare the bottom diameter and that is used to hold it for all the other operations.
The whole core is roughed with a larger cutter and then finished with a 2mm slot drill. even the holes are drilled using the slot drill, the backlash on the mill is good enough to make even 2.5 or 3mm holes acceptable.

I haven't really generated 4th axis GCode. The GCode is "per side" in subroutines and I just rotate to the correct side, then call the subroutine, then rotate again and then call a different subroutine etc.

The spindle is not through bored. The housing is made from aluminium plate. I thought about making the spindle "universal" but decided to dedicate this to horizontal. It is in quite a nice position. Even at the extents of travel the chuck of the 4th axis only just touches the main spindle, so it is fairly "safe" and does not get in the way for any other operations, I can leave it on and don't need to set it up, it just sits there ready for use on a different machine offset.

The belt I used is Syncroflex T5 (5mm pitch) I have not tried to measure the backlash, there certainly doesn't "feel" to be any but I am sure there is some.

Thanks
Simon