Topics

1

General Mach Discussion / Denford Starmill

« on: November 28, 2010, 05:01:15 AM »

Hi everyone ,

has anyone converted a Denford Starmill to modern electronics , motors , etc .? In particular the Starmill with the "NEE" controllers . Any help with this would be great .

Thanks for looking .

2

General Mach Discussion / Emco VMC100

« on: September 05, 2010, 05:44:32 AM »

I am about to embark on a new project to replace the cnc controller on my machine with a pc based Mach3 system . I have not yet decided how to move forward as i will not get the machine until next weekend . Has anyone tried and succeeded in getting one of these little lovelys up and running with Mach3 . If so can you advise on what was used and what problems I may encounter . Thanks for looking .

3

General Mach Discussion / Adding DRO to MachTurn

« on: April 23, 2010, 02:48:18 PM »

I am just finishing off retrofitting my Boxford TCL125 . The turret I had originally taken off is now back on the machine . When I start up Mach3 , all the screens show only two axis as you would expect . I intend to drive the turret using the "Y" or even the "A" axis but alas there is no DRO , no homing button , and also I do not know how to drive it from the keyboard . I have turned the turret using MDI without a problem . I am also toying with the idea of using degrees instead of the normal linear coordinate system .

Can anyone advise on how to add a DRO and homing buttons etc and also tell me how to configure Mach3 so that I can drive the turret with the keyboard and maybe swap the linear units to angular . Please bear in mind that the explanation needs to be as simple to follow as possible please .

Many thanks for looking .

4

General Mach Discussion / Prgramming & feed rates

« on: January 16, 2010, 11:06:51 AM »

Hello once again everybody

I have a Boxford TCL125 and it was running fine with Mach3 . However the computer committed suicide and had to be replaced . Thankfully I kept a record of ports and pins etc just in case of such an event . I have just put everything back as it was and I have 2 problems . The first is that my MPG no longer works , but that will not stop me using the machine so I will ignore it . The other problem is that I no longer have the ability to read the spindle speed for a reason I do not know . I can start and stop it , and I have now set it up so that the speed is not needed , i.e. s1000m03 in mdi starts the spindle and I can adjust the speed using the spindle % buttons .

Now to the question . As all my programs have been written in feed/rev , if I start the spindle in the program at say 1000rpm and it does 1250rpm I do not care . But will Mach3 allow the feed per rev or will it force me to use feed/mm ? For instance if it "thinks" the spindle is doing 1000rpm and the feed command is 0.1mm/rev will it feed at 100mm/min irrespective of whether or not it might be doing 1500rpm , or will it just complain it has no spindle speed visible ? Also if I use G94 instead of G95 , can I use G00 command and expect it to traverse at the full speed the machine is set to , or will I have to put in a feed command in every time I want to change from a rapid to a feed move and vice versa ?

The machine is going to be retrofitted once more in a few weeks so evey thing will be sorted then , but for now I have a couple of jobs to do urgently and any answers will be gratefully received .

I think I know what the answers are going to be , but if you don't ask , you won't know for sure . Thanks for looking .

5

General Mach Discussion / Boxford tcl125

« on: November 13, 2009, 09:36:48 AM »

Can anyone tell me what they have used succesfully to control the spindle of a boxford tcl125,both driving it and deriving spindle speed etc for threading.

And can anyone tell how the turret operates on the boxford and explain how to drive it through that glorious application known as Mach3.

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General Mach Discussion / Lathe losing steps I think

« on: November 08, 2009, 04:08:11 AM »

I have a Boxford TCL125 lathe which uses the standard drivers and steppers .

If I program using feed/rev the machine constantly loses steps and I have to re-home . If I use feed/minute and use a feed of 600mm/min the machine behaves ok and repeatability is great .
Anything over this and either axis may play up . I know 600mm/minute is slow , but at the moment it is what works .

The confusing thing however is that if I jog reasonably quickly the machine behaves . Is Mach3 doing something under program that I am missing or could it be the hardware ? Mechanically the slides and ballscrews have no detectable sticking points that I can notice moving them by hand . Any help would be appreciated .

7

General Mach Discussion / Setting tool offsets

« on: July 11, 2009, 11:53:59 AM »

Hi again everyone,
     I am having a spot of bother trying to set tool offsets . I use fanuc all the time at work and have tried to set the offsets in a similar manner to them without success . I have included a couple of pictures to help give you all an idea on what I am obviously doing wrong .
     The sequence is to home the machine with a 4" slip in both the "X" and the "Z" . The "Z" is set between the chuck face and the edge of the homemade toolplate (101.6). The "X" is set to 203.2 as I am in Dia mode . I then set the "Part X Zero" to zero and do the same with "Part Z Zero". I do not seem to have a problem setting the "Z" offsets , but the "X" is really getting to me now .
     The machine is using a rear tool post as can be seen with the spindle running clockwise looking towards the tailstock and the insert upside down . If I move the drill (tool n°2) in to "X" zero after setting the offset , the part DRO does not also correspond to "X" zero . The same happens with the turning tool . To my mind , the "X" axis datum should never move .
     So can someone be kind enough to explain in really basic language how to set the offsets please . The screens are all as standard if that helps .

8

General Mach Discussion / Newbie homing problem/question

« on: July 05, 2009, 10:21:17 AM »

I have no homing switches on my lathe so I use a slip gauge between the chuck and the platten type toolplate . The problem I think I am having is trying to set the machine coordinates to 50mm . When I get the slip fit , I then set the "Z" home . This puts the DRO to zero . If I try to type in 50 mm directly into the DRO , it goes straight back to zero , but part coordinates are then set to 50 mm . I have tryed setting the Homing/Limits G28 to +50 and then -50 and back to zero again . What I want is the machine coordinates to be set at 50mm when the slip fit is achieved and for the machine coordinates to verify this instead of zero .
Any ideas on my situation would be gratefully received . Thank you .

9

FAQs / 125 tcl conversion newbie

« on: May 17, 2009, 05:47:55 AM »

Hello everyone ,
I have wanted a small cnc lathe of my own for some years now . I use several at work and want to get my son in to this quite rewarding topic . I bought a 125 TCL last year but unfortunately it did not have the BBC to run it . I gave it to a friend of mine who has made his own breakout board for it and has got the lathe running in a very basic manner for me to setup as is needed .

My first question is about setting up the units for the X and Z axis . Apart from the board that has been added , the machine is bog standard . I think the leadscrew is 8mm dia with 3mm pitch . The pulley on the leadscrew is 20 teeth and 16 teeth on the motor pulley . So if I do the sums this comes to 0.4166 . I am assuming the motors are 200 step but I do not what the drivers are set up for . From here I get a bit lost . Can anyone help me with the next couple of steps please ?

Thank you for looking .