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Saracen
06-11-2014, 01:42 PM
I've recently purchased the Boxford TCL 160 from Bartell of this parish:

http://www.mycncuk.com/attachment.php?attachmentid=13809&stc=1

and intend to convert it using a Planet-CNC Mk2/4 board which came with a previous router purchase.

The lathe arrived on Tuesday, sitting on a mini pallet and wrapped in about 20 quids worth of bubble wrap, so survived the trip intact.

A quick play in manual mode confirmed that everything works as expected.

I'm planning on using as much of the electronics as possible, so today I removed the link cable between the processor board and the driver board and made a quick and dirty connection of the step/dir/gnd connections from the Mk2/4 to each of the step/dir connections for the X, Z and ATC motors and all worked perfectly.

I'm a little stumped as to how to connect the motor drive to the Mk2/4 but once I've disentangled more of the cabling I should see what's required.

The overall plan is to remove the processor board and fit an ITX motherboard in its place, with the driver board still sitting at the top of the mounting legs, so that it's in the draft of the cooling fan. That way it remains a stand alone unit, with just a monitor to wall mount and probably a wireless keyboard and mouse.

I also need to connect up some opto-isolators between the homing switches and the Mk2/4, and work out a wiring plan for the various safety switches.

Adrian.

Saracen
07-11-2014, 01:10 AM
Turns out the machine I have is not the one in the picture above, but probably the one behind it.

Note to self - the X and Z homing sensors appear to be NPN, so will need to configure the opto-isolators accordingly.

Adrian.

Saracen
07-11-2014, 06:45 PM
I've ordered the Planet-CNC Output Control board, in order to generate the 0-10V signal to control the speed of the lathe spindle, but the Mitsubishi inverter which is fitted to this lathe uses two separate signals to control the direction.

From the Mitsubishi manual:

STF - Forward start input signal - Motor starts rotating in forward direction when STF and P24 are short circuited. Stops when opened.

STR - Reverse start input signal - Motor starts rotating in reverse direction when STR and P29 are short-circuited. Stops when opened.

There are relays for this purpose on the driver card already, but I presume I need to generate two separate outputs from which ever Mk2/4 output pin I designate for the purpose of spindle direction ?

The lathe needs to rotate in both directions as the turret holds the cutting tools behind the work piece, so turning etc happens in reverse, but drill bits require the spindle to rotate in the forward direction as per a normal lathe.

I guess I could just buy a good range of left handed drills ...

Adrian.

Saracen
08-11-2014, 12:00 PM
A quick bit of boolean logic algebra proves that a single 74C00N Quad NAND gate chip will allow me to make one NAND gate and one AND gate, and hence generate two separate opposing logic HIGH signals from the single LOW/HIGH output of the Mk2/4 board. Have ordered the required chips and header boards from eBay, which can also be used to the two opto-isolator boards for the proximity switches.

Adrian.

m_c
08-11-2014, 09:13 PM
Are you sure those tools are the correct way up to be on centre?
.
Normally rear mounted tools are upside down, so they still cut the spindle rotating clockwise, and I would of thought something aimed at training would follow that convention.

Saracen
09-11-2014, 12:04 AM
Yup. All the Tutorials in the programming manual talk about running the spindle in reverse for turning and forwards for drilling.

Adrian.

Saracen
23-11-2014, 01:15 AM
It turns out I was over-thinking this, as usual.

The inverter direction is controlled by two relays on the old Boxford driver board, one for each direction.
One end of the coil is connected to +12V. Shorting the other end to Ground activates the relay.

Using the Planet-CNC Output Board, I have connected the NC connection of Relay2 to the Boxford CW direction relay, and the NO connection to the Boxford CCW direction relay.

The common connection on Relay2 is connected to the NO connection on Relay1.

The common connection of Relay1 is connected to Ground.

When the Spindle enable signal is active on Output1, Relay1 connects Relay2 to Ground, activating the spindle.

The Spindle direction signal on Output2 determines whether the NC or NO connection on Relay2 is connected to Ground through Relay1, and hence which way the spindle turns.

No other wiring required :D

Adrian.

Saracen
21-01-2015, 12:11 AM
Not much movement on the conversion front due to other, more pressing projects, though I do now have the old control panel jogging buttons wired up, so I can move things from the panel, rather than the PC.

Next task is to wire the turret motor control to an Arduino, so that I can use the old control panel "Turret Index" button to rotate and lock the turret once for each press.

Adrian.

Saracen
23-01-2015, 11:05 PM
Arduino connected to the turret driver tonight and a quick hack of a program put together.

Three buttons have been programmed; the first moves the turret CW whilst pressed, the second moves the turret CCW whilst pressed and the third moves the turret round 45 degrees and backs it into the pawl.

Seems to work, but a few stutters in the rotation and the locking isn't even amongst the different tool positions.

Adrian.

Saracen
25-01-2015, 12:14 PM
Wired up the index opto slot sensor on the spindle shaft to the Mk2/4 board. 12V power comes from the opto isolation board I'm using on the homing switches.

Spindle speed is now displayed, alongside the demanded speed, and they seem to be reasonably close over most of the range.

Adrian.

Saracen
02-02-2015, 07:06 PM
I've decided to drop the Arduino method and just use gcode to change the tools. Much simpler wiring and seems quite straightforward.

However, this lead onto some problems with the turret. Sometimes it would turn and others it wouldn't, either backwards or forwards.

I've stripped it down tonight and found a number of things.

First is that you have to remove the X axis stepper to gain access to the hole through which you release the shaft of the turret stepper.

Having removed the turret and gained access to the cam and pawl, the seemed to be an excessive amount of force required for the cam to push back the pawl.

The pawl tension is adjusted by the screw which passes through a stack of disc springs. Backing that off just a little eased the pressure to the point where the turret rotated freely.

With it all apart, I've taken the opportunity to lubricate all the sliding surfaces.

Whilst putting it all back together again, I found that there should be two alignment dowels between the turret itself and the shaft which powers it. These are missing, so the only thing holding it in place are the four fixing screws. As there is some clearance in their holes, the slop I could feel when manually handling the turret were caused by it slipping on the shaft. Two 5x15 dowels are required to keep the turret true.

Adrian.

Saracen
03-02-2015, 07:38 PM
Two steps forward, one step back:

After backing off the pawl screw, there wasn't enough tension to hold it in place, so the clack of the turret cam moving round unscrewed it.

Removing some of the springs and tightening it up fully solved the unscrewing problem, but then I found the hole for the screw breaks into the operating area of the cam, so when the screw was fully tightened, the cam caught on the end of the screw.

By adding a brass washer, and adjusting the layout of the disc springs, I was able to get the tension right, and the screw can't unscrew any more as it's now flush with the back face of the turret block, so held in position by the X axis block.

Next, I found that, even after adjusting the tension of the spring, the turret was still stalling at various points. Having tried all sorts of cures, I've had to back off the pre-load on the main cam shaft bearings. Originally, I was too tight to turn by hand. Having removed the shaft, I can't feel any roughness in the bearings themselves, which are BR-7005-2RS angular contact bearings, so I reassembled it with just a smidgen less pre-load than before. It's still tight to turn, and there's no appreicable play or end float, but it now turns on command without stalling.

A little work on the gcode and it looks like an 8.75 CCW turn followed by a 1.75 CW turn is all that is needed to rotate the turret one tool position and lock it back into place.

Hopefully, the 5mm dowels should arrive tomorrow, so I can get the turret aligned and re-installed.

I've already written some simple gcode scripts to make various brass axles. Now the auto-changer is working, I should be able to combine some of them.

There's no homing facility on the turret, so I'll need to make sure that lathe is set to tool 1 at the start of each program.

Adrian.

Saracen
14-02-2015, 12:01 AM
5mm dowels arrived and have been inserted into the turret. Definitely no play now when trying to rotate the turret by hand, which was noticeable before.

I've written some Gcode scripts to perform tool changes, and am still struggling with getting the turret to a known safe position before initiating a tool change. As the parting / grooving tool stands so proud of the turret, it will hit the Z axis slides if the turret is rotated with the X axis at anything other than near the +ve limit. Still waiting to hear back from Planet-CNC as to why G53 moves are apparently affected by tool offsets, which is why no progress recently.

The TNMC inserts arrived today, so I'll be able to repopulate the original Boxford threading tool, as that is left handed and is easier to accommodate in the gcode I'm writing, and requires less material to be removed to make space for the tool head.

Adrian.

JAZZCNC
14-02-2015, 11:42 AM
Still waiting to hear back from Planet-CNC as to why G53 moves are apparently affected by tool offsets, which is why no progress recently.

When you say affected by tool offsets what exactly is happening.? Your not using it in incremental(G91) mode are you.? G53 can only be used in absolute(g90) mode and cutter radius should always be cancelled prior to move.

Saracen
14-02-2015, 12:02 PM
The details are all laid out here:

http://forum.planet-cnc.com/viewtopic.php?f=5&t=1846

This is the test program:


%

G18 ( Force XZ Plane )
G21 ( Force Metric Dimensioning )
G40 ( Force Tool Nose Compensation To OFF )
G80 ( Cancel Any Modal Motion )
G90 ( Force Absolute Coordinate Positioning )

G53 G00 X60 Z100 ( Move Turret To Safe Position For Tool Change )
G04 P10 ( Pause For 10 Seconds To Allow Notation Of Axis Locations )

G91 ( Force Relative Coordinate Positioning To Stop Turret Reversing To Location )
G00 A16 ( Rotate To Tool Position 3 )
G01 A-2 F100 ( Rotate Back Against Pawl At Feed 100 )
G90 ( Force Absolute Coordinate Positioning For Machining Passes )
T3 ( Force Tool Change For Tool 3 )
M6 ( Force Use Of New Tool )
G43 H3 ( Force Use Of Tool 3 Offsets )

G00 X30 Z60 ( Simulate Program Moves )
G04 P10 ( Pause For 10 Seconds To Allow Notation Of Axis Locations )

G53 G00 X60 Z100 ( Move Turret To Safe Position For Tool Change )
G04 P10 ( Pause For 10 Seconds To Allow Notation Of Axis Locations )

G91 ( Force Relative Coordinate Positioning To Stop Turret Reversing To Location )
G00 A46 ( Rotate To Tool Position 1 )
G01 A-2 F100 ( Rotate Back Against Pawl At Feed 100 )
G90 ( Force Absolute Coordinate Positioning For Future Machining Passes )
T1 ( Force Tool Change For Tool 1 )
M6 ( Force Use Of New Tool )
G43 H1 ( Force Use Of Tool 1 Offsets )

M2 ( End Program )
%

I start the machine off with no offsets on any tools. Tool Offset is set to "Not Used" in the Tool Change settings page. Before every pass, the tool is homed using the limit switches, which leaves it at X65, Z105.

What I'm seeing is that the final absolute position at the end of the program is the "G53 G00 X60 Z100" commanded position, but minus the Tool 3 X offset value. That in itself is odd, but it's also affecting both the X and Z axes, by the same amount. In other words, the final Z position is minus the T3 X offset, not the T3 Z offset:

To get a safe automated tool change, I need to be able to get the carriage to a known safe location, and at the moment I can't do that. Changing from G90 to G91 also seems to have the side effect that the next movement control, on any axis, caused motion on all axes. This usually results in the machine going out of limits, but has also caused a couple of turret/chuck interfaces.

Adrian.

Len-Tikular
05-03-2015, 08:12 PM
Hi Adrian,
I have just received my Boxford TCL160. I switched it on and from the panel can move both axis, rotate the turret and spin the chuck both fwd and reverse so that's a good sign. The jaws don't open and close even although there are buttons on the panel.
I have purchased the manuals which should arrive tomorrow. These have all the wiring diagrams I believe so if you are in need of any let me know.
I plan also to convert to Mach3 operation so I sure could use some help, any schematics or drawings that you might have and would like to share I would be grateful for.
I would be really grateful for any help you can give.

Best regards

George

Saracen
06-03-2015, 01:38 PM
Hi George.

The jaws require a pneumatic system to operate, so if your lathe has that system fitted, you would need to attach a compressor. Mine has a manual chuck, so I've not looked into that.

The only drawings I have came from a copy of one of the manuals, so you should have that now.

I'm using a Planet-CNC Mk2/4 board to control the original stepper drivers etc, wired up to the original homing and limit switches. It has very limited inputs, so this does mean you lose the use of a lot of the front panel buttons, but I have managed to get the jogging ones connected again.

I'm having problems with the Planet-CNC software, as I think it's designed mainly for routers rather than lathes, so I'm also looking at the Eding controller, in case the Planet-CNC one falls through. Both of these use their own software, so I've not investigated Mach3 for this machine.

Adrian.

Len-Tikular
08-03-2015, 07:13 PM
Many thanks for the reply Adrian,
No air on my TCL160(1994) so manual only for the chuck.
I have a limit switch on the body of the cabinet which is activated by a rod on the Z Axis. Clearly this serves to prevent the tool post clouting the chuck. (Good idea)
I read somewhere that depressing both Left & Right feed together that the machine should execute a 'Homing' action.
This didn't work for me unless I misunderstood the methodology. Any Ideas ?
Should there also be a Limit /Homing switch for the X axis ?
I purchased a spare set of boards which were removed from a non turret machine together with a Small format Motherboard SBC-GX1 complete with compact flash with Software 4.3.1 installed.
I wonder whether this software can be upgraded to V5 or even 6. Any ideas on this ?
The PC motherboard I'm told was fitted inside a TCL160 ? There is no such board in mine. Did earlier machines have a PC inside ???
For the moment, I will try and get the native software running and see exactly what the machine is capable of doing.
I will then convert it as you have done so if you have any schematics of your arrangement or any pictures that you'd care to share I would be very grateful.
Meanwhile
Best regards

George (Oldham Lancs)

Saracen
08-03-2015, 07:34 PM
Does your TCL have three or four flexible conduits running from the back of the cabinet ?

If it only has three then it is probably not fitted with homing switches.

I don't believe the PC motherboard fits inside the case. There is a CPU board in there but that's just to read the various switches, take the control input from the serial port and generate pulses for the stpper drivers.

I believe Boxford will sell you a copy of the current software if you let them know the serial number of your lathe. From memory it was about 500 to purchase. I'm doing my own thing now so am not pursuing that route.

Adrian.

Len-Tikular
08-03-2015, 08:02 PM
Only 3 flexi's so you're probably correct, no homing.
That may impact on the new software.
George

Saracen
08-03-2015, 10:13 PM
This picture:

http://www.boxford-software.com/spares/NewImages/160/slide%20assy.png

shows the location of the two homing sensors - the two salmon pink parts.

Would it be possible to retrofit them ?

Adrian.

Len-Tikular
09-03-2015, 07:40 PM
This picture:

http://www.boxford-software.com/spares/NewImages/160/slide%20assy.png

shows the location of the two homing sensors - the two salmon pink parts.

Would it be possible to retrofit them ?

Adrian.

Should be Possible, I'll check the wiring diagramm

George

Saracen
31-03-2015, 11:44 PM
I've been having problems with the Planet-CNC software so, seeing as I have a UC100 motion controller left over from another project, I thought I'd take the plunge and swap them over.

As I've been using the Boxford driver board, I made up a new loom, so that I needed to disturb the current wiring as little as possible.

Loaded the UC100 software, loaded the included demo of Mach3, wired up the newly purchased BoB and fired her up again.

And all that happens is all three steppers rattle and bang alarmingly. With the UC100 disconnected, there's no noise, so I don't think it's interference on the control lines.

Seems I need to do some digging in Mach3. If anyone has an XML file for Mach3 for use with the Boxford stepper electronics, it would be gratefully received.

Adrian.

keith wainwright
22-04-2015, 06:35 PM
Hello .I have just purchased to very same machine exactly like yours and it work very well.I have a Planet-CNC Mk3 board and hope to use this to connect to a pc with the planet software Could you help with wiring diagrams , plans or any info at all as i am an engineer and not very experienced at all with electronics. I don't mind purchasing whats needed but don't see the sense in scraping things that work so well. Please help thanks

DrBrodie
23-05-2017, 12:33 PM
Hello Saracen,

I work in a school and we have a Boxford 160 like this one. We are having turret indexing issues. I don't suppose you have a diagram of the turret assembly so our technician can strip it down? Only manual I can find is online for 60! Zero chance of school buying that for us.

Thanks in advance,

Neil Brodie

(DrNBrodie at gmail.com)

keith wainwright
23-05-2017, 02:12 PM
Hello please let me know the precise problem as I have striped a few of these and I may be able to assist. They are not very complex and parts and diagrams are on the Boxford website.

Saracen
23-05-2017, 02:30 PM
Here's the page on the Boxford Spares site:

http://www.boxford-software.com/spares/160Turret2.html

I don't have a manual for it; I just dismantled slowly and made notes as I went.

My problem was also the indexing, in that the pressure from the springs on the pawl would stall the motor and stop the thing from turning. I cleaned it all out and re-greased it and it has been fine ever since.

Adrian.

keith wainwright
23-05-2017, 02:37 PM
I did exactly the same for the same problem but I also increased the pulses and it helped a lot it also made locking more precise.

Saracen
23-05-2017, 03:05 PM
I did wonder if the motor was getting weak but it seems to have been fine since.

Would changing the motors and/or drivers speed up the movement ? I'm still using the Boxford drivers and motors, but controlled with a PlanetCNC Mk2/4 board.

Adrian.

DrBrodie
23-05-2017, 03:46 PM
Thanks for the spares link, it helped a lot. We have got inside and the issue seems quite obvious... 😂

21749

Saracen
23-05-2017, 03:55 PM
Ouch :hurt: :hurt: