Messages

81

General Mach Discussion / Re: Boxford 160TCL

« on: April 20, 2008, 01:15:45 PM »

Ian,

Yes, I have had the motor running and can vary the speed using a potentiometer wired into the speed controller.
When I feed the full 10v reference from the speed controller back into it, the motor it "hunts" as though it can't do full speed.
upto about 8v and it is ok and varies nicely with the input voltage.

The time taken to slow down is too long really so I would like to wire up some kind of braking. I am having trouble visualising the changeover relays you describe. I have attached a pic of the contactor which is present at the moment.

The contactor flips the direction nicely too so all I need to do is somehow get it to stop before I energise the contactor. There is a manual switch on the top of it and it reverses the direction ok but it is a bit violent!

Thanks
Simon

82

General Mach Discussion / Re: Boxford 160TCL

« on: April 20, 2008, 07:46:09 AM »

Ian,

Thanks for the info. I am trying to work out the motor reversing circuit needed but am not sure I understand the manual, it goes on about electrodynamic braking and tells you the size of the resistor needed but the circuit diagrams are unreadable to me.

If you have the time could you take a look at the attached pdf and let me know if you understand it? They don't seem to have bothered to label anything in the wiring diagrams and I haven't a clue as to what to do.

Thanks
Simon

83

General Mach Discussion / Re: Boxford 160TCL

« on: April 20, 2008, 03:33:17 AM »

Does anybody have a wiring diagram for a Lenze DC spindle?
There are 5 wires to it...
I know what 3 of them are for. Two are for the main motor connection and can be reversed to reverse the direction, the third is the ground connection but there are also 2 yellow wires which were originally connected to the guard switches and e-stop button.
I can only imagine that they are an electromechanical brake? I have tried shorting them together but they don't seem to do anything, presumably they need a voltage to be applied? But what voltage?

Thanks
Simon

84

General Mach Discussion / Re: Boxford 160TCL

« on: April 14, 2008, 05:01:31 PM »

Well, the mechanics have cleaned up nice!

85

General Mach Discussion / Re: Boxford 160TCL

« on: April 13, 2008, 01:49:33 PM »

Ian,

Reading the Lenze manual seems to imply that the speed controller handles the slowing down and stopping of the drive during the changeover. I will have to see when the BOB arrives.

I have some 2 stack 23 size steppers from Motion Control Products on my mill. If the original ones on the Boxford are no good I will try them. I have been disapointed with the torque from them MCP steppers and have even installed a 3 stack one on the Z axis of the mill but I suspect it has more to do with the 24v power supply and the StepMasterNC controller. I look forward to seeing what Geckos can do! My StepMasterNC controller couldn't even make a single stack stepper turn my rotary table with any reliability!

Simon

86

General Mach Discussion / Re: Boxford 160TCL

« on: April 12, 2008, 08:00:11 AM »

Ian,

Many thanks for all your comprehensive replies, it is much appreciated...

Mine is indeed a DC drive. I have the PDF manual for the drive from here...

http://akb.lenze.de/AKB-englisch/infopool.nsf/1429b1338a70e30b41256a2900343844/b347039433d8d32bc1256d880037c499/Body/M2/530_Speed_controllers_1202_EN.pdf?OpenElement
I have yet to digest the information though.

It is identical to the one in this post...
http://www.machsupport.com/forum/index.php/topic,1645.0.html
Even the odd external board by Simpletron is the same.

I bit the bullet this morning and ordered 3 off 203V Geckos and a CNC4PC C11G BOB and while I was at it I ordered their C3 - Index Pulse Card as it looked like is might do the spindle index and was cheap enough to add on just in case.
I figured the extra £15 for the peace of mind of the 203V against the 201 was worth it.

Do you use any of the original control panel on your boxford? Mine is a complex affair with a full PCB behind it with all sorts of components on it, I think it might be just easier to make a new panel!

Thanks
Simon

87

General Mach Discussion / Re: DC Spindle drive question, What to do with it!

« on: April 12, 2008, 04:59:01 AM »

Did you ever sort this Spindle drive out?
My Boxford 160TCL has the same drive and uses a relay to switch the direction.

I was planning on using the speed control on a CNC4PC C11G breakout board to control the speed, will this work?

If you did sort it, How did you connect up the relay to get the direction to switch?

Also how did you connect up the spindle encoders? The lathe has 2 encoders on it, one with 1 slot and another with loads of holes (I have not counted them yet)

Thanks
Simon

88

General Mach Discussion / Re: Boxford 160TCL

« on: April 11, 2008, 06:53:53 PM »

Ian,

I will have another look at the stepper board over the weekend but when I just disconnected the Z80 board, the stepper board wouldn't even power up. The entire front panel is also connected to the stepper board and even that lost it's functionality.
If I had a wiring diagram then I might be able to figure it out but it isn't immediately obvious what is wrong. What I don't want to do is spend ages figuring it out only to find that the board packs up after a couple of months and I have to rip it all out anyway.

I got the lathe for a bargain price so I don't mind putting some money into it. I guess I could go for a 201 for the turret and 203V's for the main axis.
Reading the Gecko site, I did like the way the 203V's automatically transition from microstep to full step depending on the speed, that is a nice feature.

Does your machine have the Lenze inverter in it still? Mine has an odd board mounted onto the same plate as the inverter and it obviously has something to do with it but I can't work out what it does. I spent most of tonight trying to figure out the contactor wiring and how it switches the spindle direction. I'm still not sure I fully get it!

Simon

89

General Mach Discussion / Re: Boxford 160TCL

« on: April 11, 2008, 04:55:12 PM »

Having looked at the electronics and tried to remove the Z80 board, it looks like the two are interdependant. I am not sure it is worth the trouble!

So...

I have been thinking of getting the Gecko 201's for the X and Z axis. Is there any need to go to the 210? or better spec? Why would I want to select the microstepping? is it down to the limit of number of steps MACH3 can output, 25Khz??

The gecko drive seems a bit of overkill for the turret as the operation of it seems fairly dumb. It looks like "rotate clockwise for x degrees and the anti clockwise for y degrees which then stalls the stepper motor?
Is there a simpler cheaper solution I should be looking at for the stepper driver?

I see that CNC4PC do a specific breakout board for Geckos called the C11G ? I could't find any difference in the documentation, anybody got any idea what the difference is?

Simon

90

General Mach Discussion / Re: Boxford 160TCL

« on: April 10, 2008, 05:50:17 PM »

Ian,

The steppers are 57mm diameter. so yes, I think they are Size 23.
That PDF was what lead me to believe it was a bipolar driver. I have the manual for the Inverter now too thanks to Google.
I have just about stripped the cabinet now (writing down the wiring as I go!) Everything looks like it will clean up really nice. Most of the rust is very superficial.

Simon