View Full Version : Boxford 125TCL CNC Lathe re-build

27-01-14, 09:38 PM
CNC stuff has always been an interest of mine and I finally got the chance to pick up a couple of machines that just needed a bit of modernising.

Here's a Boxford 125TCL Lathe I picked up a couple of weeks ago. This Lathe was made back in 1986 and was purely as a School/College training lathe :eek: I never even knew they had CNC stuff back then.


It's only a small machine but with the benefit of having the tool changer i'm hoping to be able to get more stuck in to multi tool turning without having to keep swapping tools :D

Generally, the machine is in good condition. It came with the BBC Micro computer to run it along with software for this, a 240TCL and the 260VMC that I got as well. A massive bonus was that I got wiring schematics for a the Boxford TCL's and VMC's as well (almost impossible to get hold of). They were a great help. Boxford won't supply ANYTHING to Joe Bloggs out in his shed, they have contracts with learning authorities which prevent them from doing so (and in return they get to rape the LEA's :shake:).

As well as having the turret tool changer it came with a manual chuck and a pneumatic chuck. Hopefully put that to some use in the near future. The downside is that at some point a previous owner had decided to hacksaw out the spindle drive board following what looks like a bit of a capacitor burn up :(

Other than that, the electrics are all there and working.


As I wanted to ditch the BBC controller I decided to opt for a USBCNC board from Planet CNC (http://www.planet-cnc.com) and figured i'd swap out the stepper drivers and steppers at the same time. I had a couple of short nema 23 steppers so just ordered one for the Z axis and 3 Leadshine DM442 drivers.

Motors fitted, time to drop it back to manual'ish control just to check everything moved ok :D


The slow part was working through the original wiring and stripping out what wasn't needed any more and trying to find all the bloody safety switches Boxford seemed to like hiding on the machines. Last night, the wiring was finished for all the new kit and it was given it's first test.


Only a real short test as it was just after midnight and I had an early start this morning.


The next bits are :-

Tune the motor settings in the USBCNC software.
Sort the lack of spindle drive.
Re-wire the front jog panel to the USBCNC board
Wire and set up the optical switches on the spindle to manage CSS and Index pulse for threading.

27-01-14, 10:04 PM
ok,, does anybody know what he,s on about??:beuj:
seriously though well done 'guv keep the updates & vids coming.

Slow & Low 400e
28-01-14, 01:14 AM
:eek: wires
please explain with plenty of pics :tup:
ps I remember bbc computers. I'm not sure I'll get any cool points from the yoof of today for that though.

28-01-14, 08:39 AM
ok,, does anybody know what he,s on about??:beuj:
seriously though well done 'guv keep the updates & vids coming.
Yeah - kinda, thought that these sort of machines were best suited to repetition work churning out thousands of pieces rather than 'one offs'. Lucky they are in good condition - in my day ex-college stuff would have been serious abused by students.

28-01-14, 09:41 AM
Hopefully they will be doing repetition work :)

The main thing is I can do almost anything on a computer so knocking up a part in Solidworks is easy for me then I can have the machine make it. If I tried to just make it manually on my other lathe it wouldn't turn out anywhere near as good :D

Plus, I've always had an unhealthy interest in making computers run motors etc. :D

28-01-14, 09:42 AM
I set the motor tuning last night and ran a quick gcode test to see what backlash was present in the machine. The x axis returned to bang on the starting point and there was 0.05mm variance on the z axis :D


28-01-14, 09:52 AM
Just had a look at our records for my lathe at work...is got .027 backlash..

yours looks to be in very good nick..I have some micrometers and stuff in the shop you can have.

28-01-14, 09:55 AM
Sounds good Liam :tup:

I'm really looking forward to getting the mill working. Never broken anything on a mill before :D

So far i've had it traversing at 2000mm/m but obviously that with no load and I doubt that the machine will be able to cut that heavy ... a second time :incheek:

28-01-14, 10:05 AM
You will be surprised what they can cut at...remember that they are built for novices to train on..

you only have to miss a decimal point or go clockwise instead of anti clockwise...see what i mean .

28-01-14, 10:09 AM
True, I know the roughing canned cycle in the Boxford software on the lathe will take 3mm stabs at the workpiece :eek:

28-01-14, 11:02 AM
I'm doing 3mm cuts on an 800mm dia titanium forging at the moment..The load meter is on 1%..:D

i hate my job..:incheek:

28-01-14, 05:45 PM
When I did my apprenticeship back in the 60's some of the really large machinery (and lathe's) were ex WD - not 2nd world war, but 1st world war. And whilst backlash etc was generally far, far more than any modern lathe back then, once you 'knew' the machine you could allow for all its quirks and turn out some really accurate and high quality work. This is where the lathes at the local technical college were problematical. As we only attended one day a week the lathes, mills etc being used and abused by successive students were never the the same operationally from one week to the next - making it impossible to turn out accurate work and achieving good marks.

28-01-14, 06:57 PM
CNC was introduced just as I was finishing my apprenticeship and the union tried to ban them for fear of us loosing our piece work money.
I left as they were coming in and went over to sheet metal fabrication and welding
Did they ever catch on

29-01-14, 01:43 AM
According to the build sheet I was 8 when this machine was made :D

02-02-14, 10:16 PM
Been waiting to get the replacement spindle drive board so I can have the machines spinning.

In the meantime, I replaced all the electronics on the milling machine and decided to do a quick pen test :D
Best to have the volume low lol, the aluminium block isn't perfectly flat so you get the occasional blackboard screech off the pen nib.


03-02-14, 11:36 AM
And it makes siren noises when you do circles. ..:D

Jungle Jim the white
03-02-14, 01:29 PM
Some very nice work and some lovely gear :)

puts my piece of crap to shame. Keep the vids coming, I have a target to aim for now :D

Slow & Low 400e
03-02-14, 06:21 PM
Oh no. Even though I don't need a Cnc lathe and can barely use my standard one, I now think I "need" a Cnc lathe.
A very interesting build thread.

03-02-14, 06:25 PM
Very impressive guv' now do it "freehand" :D "nah just foolin' wid ya!";)

03-02-14, 07:42 PM
Love it. Will get the drawings to you for the valley plate breather. I aint forgot 'dude'

04-02-14, 12:20 AM
Very impressive guv' now do it "freehand" :D "nah just foolin' wid ya!";)

I can't do shit all freehand :pcnoob: That's why I love CNC :D

04-02-14, 12:22 AM
Some very nice work and some lovely gear :)

puts my piece of crap to shame. Keep the vids coming, I have a target to aim for now :D

Does help when it's been built as one to begin with. Cheating really lol. The whole thing weighs in at nearly 500KG :eek:

Jungle Jim the white
07-02-14, 07:26 AM
500KG, crikey!

07-02-14, 09:05 AM
Yep mate. Big chunky steel frame to keep it solid.

11-02-14, 09:50 PM
I thought some of you guys might find this interesting? http://www.cnccookbook.com/CCHomeMachineShops.html [if you didn't know it already]

05-09-14, 08:36 AM
Hello roadrunner, Just discovered the forum, and wandered if you could help me with converting a TCL 240.
I'm in West mids myself and perhaps you might have the time to show me your machines?