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Author Topic: 3-Axis Mill Retrofit, Servo and performance questions! Alot of functions?  (Read 16540 times)

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Hello my name is Oscar and im new in here.

Im working as an Automation engineer in sweden.

I have an 3 axis CNC mill at home with an old Bosch cnc system on that im planning to change to something new and i have been looking alot at the Mach 3 and i have some questions i hope some one could help me with?

First i wanna say that i have been looking at some other systems also like, Fanuc, Beckhoff and so on. But the price is far alot more money.
1) I wounder how good is the performance in the Mach 3, compared to more expensive systems like, fanuc, siemens?

2) If i have the right Servo amplifiers and motors and my mechanical on my machine is good, can this system then performace the same quality as the big systems from Siemens, Fanuc ?

3) I have been looking at Omron Sigma II drives at 2kw (8Nm on motor) for the axis movements, Is there any idea to use Absolut encoders on the motors or that is just overkill? Or inkremental is good enought?

4) I have also been looking at the SmoothStepper USB card, is this something to recommend when i use drives like this? Or maybe this is something to recommend anyway now that is excists?

5) Is the SmoothStepper card more stable than the parallelport system?

6) Is there any special good breakout card that you guys would recommend me to buy? Is it good to have the Chargepump function on the breakout card?

7) If i would like to have an MPG i think it's called. this hand held pendant with an handwheel on and with switches. Do i connect this to the breakout card? Some one know were i can this that is compatible with the Mach 3!

8 ) Is it possible to connect the pulse train from the drives to the Mach 3? Or this is there no meaning with it? If i have got it right there is no closed loop in the mach with the drives?

9) Can the mach 3 calculate the load of the axis drives and show it on the monitor, like fanuc and all other systems have? or do i need to connect an feedback from my drives to the mach 3 if its possible? Maybe over the Modbus from an PLC system?

10 ) Can i use an Axis drive like the 4th servo axis and use it for my spindle on the mill? Or the only spindle control is on the PWM output from the breakoutcard?

11) Is it possible to use the spindle control for more advanced functions like making threads? Fast ramping down, driving on low controled speed?

12) How many rows with G-codes can i have in an program? Is it the harddrive on my computer that will do the limit?

I hope some one maybe could help me with my questions.

Best Regards
Oscar Larsson


« Last Edit: April 26, 2009, 03:34:08 PM by Oscarl »

Offline Hood

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Hello my name is Oscar and im new in here.

Im working as an Automation engineer in sweden.

I have an 3 axis CNC mill at home with an old Bosch cnc system on that im planning to change to something new and i have been looking alot at the Mach 3 and i have some questions i hope some one could help me with?

First i wanna say that i have been looking at some other systems also like, Fanuc, Beckhoff and so on. But the price is far alot more money.
1) I wounder how good is the performance in the Mach 3, compared to more expensive systems like, fanuc, siemens?

Hard to say as I dont really know what you mean.
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2) If i have the right Servo amplifiers and motors and my mechanical on my machine is good, can this system then performace the same quality as the big systems from Siemens, Fanuc ?

I would say yes


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3) I have been looking at Omron Sigma II drives at 2kw (8Nm on motor) for the axis movements, Is there any idea to use Absolut encoders on the motors or that is just overkill? Or inkremental is good enought?

I use Incremental with my AB drives but maybe your Sigma require absolute, I dont really know, but whatever the drives support is what you need.

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4) I have also been looking at the SmoothStepper USB card, is this something to recommend when i use drives like this? Or maybe this is something to recommend anyway now that is excists?

The SS is really needed if you are using industrial type drives due to the high encoder count.

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5) Is the SmoothStepper card more stable than the parallelport system?

The parallel port is stable and as far as I am concerned the SS is as well. I have the SS on all my machines, a few things are still not implemented such as backlash and spindle is not perfect on CSS for me but that will get fixed through time I am sure and certainly has not stopped me using my lathe.

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6) Is there any special good breakout card that you guys would recommend me to buy? Is it good to have the Chargepump function on the breakout card?

I use the PMDX122 on all my machines and can highly recommend it[/quote]

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7) If i would like to have an MPG i think it's called. this hand held pendant with an handwheel on and with switches. Do i connect this to the breakout card? Some one know were i can this that is compatible with the Mach 3!

Yes connect to the breakout and there are a few around, I made mine myself using the PoKeys for I/O and analogue Inputs for FRO and SRO.

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8 ) Is it possible to connect the pulse train from the drives to the Mach 3? Or this is there no meaning with it? If i have got it right there is no closed loop in the mach with the drives?
You can connect the encoders to Mach but as you have said it is Open loop so it will be for monitoring purposes only.  Your drives close the loop so that is not needed when you are talking about Industrial type servo drives as they will close the loop very effectively.

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9) Can the mach 3 calculate the load of the axis drives and show it on the monitor, like fanuc and all other systems have? or do i need to connect an feedback from my drives to the mach 3 if its possible? Maybe over the Modbus from an PLC system?
That will be a function of your drives, the ones I have have analogue outputs and I have selected and scaled the current and put it to a meter on my console, it shows the spindle load. It could be put into Mach via Analogue inputs on a PLC and I may at some point do this myself but for the moment I am happy with a real meter.

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10 ) Can i use an Axis drive like the 4th servo axis and use it for my spindle on the mill? Or the only spindle control is on the PWM output from the breakoutcard?
You can use a Servo drive as a spindle and set it up to use step and direction, I have a 12.5Kw AC Servo on my lathe for the spindle and a 8KW AC Servo on the mill I am presently retrofitting.

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11) Is it possible to use the spindle control for more advanced functions like making threads? Fast ramping down, driving on low controled speed?
At this time the spindle on the mill does not support rigid tapping, it can be done using a floating holder or you could use swap axis feature but unfortunately that is not supported by the SS at this time. Speed control if using a servo for the spindle is no problem, just tell the spindle what sp[eed to do and it will be exact :)

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12) How many rows with G-codes can i have in an program? Is it the harddrive on my computer that will do the limit?

Unlicenced Mach is limited to 500 lines in Mill and 250 in Turn. Licenced versions have a limit of 10,000,000 lines.

Hood
Hello.

It seems like you have been using this for a while and are happy with it.

2) That sounds really good.

3) Ok. But every time i startup the system i will need to reference drive my mill in all axis? I tought if i used absolut encoders i would not need to do this? My drives can handle booth inkremental and absolut encoders.

5) What do you mean with backlash?

6) Ok. i have been looking at this card. Just so i have got everything right. I take the USB from my computer to the SS card and from that card over to the brakeout card right? Will the SS card and drive on my computer need more CPU power or it don't need more power to get this high frequency?

7) But i can also use A / B  pulse train for the position wheel and connect to my brakeout card?

8 ) Do you connect your drives to the mach 3 so you can se the position?

9) Ok. But then i will have to put the analog inputs to my plc? Do the breakout bord have analog inputs for this?

10 ) Do you have any gearbox then on your mill?

12) 10 000 000 Lines is pretty mutch more than my Bosch CNC Alpha 3 can handle today  :o :o :o

It seems like you are using this alot, What kind of servodrives do you use in your machines?

All things like tool data and so on are supported by the software?

Is it possible to have one home position with the switches on my mill and then have more zero points, Like if i put up my work piece and make X, Y and Z zero to that piece? I hope you understand what i mean.

Do you have an postprocessor on the outside were you make all your G-Codes?


Best Regards
Oscar Larsson

Offline Hood

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3) Ok. But every time i startup the system i will need to reference drive my mill in all axis? I tought if i used absolut encoders i would not need to do this? My drives can handle booth inkremental and absolut encoders.

Yes you will need to home on every restart but really you would need to do that in anycase whether you had absolute or incremental as Mach itself is open loop.


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5) What do you mean with backlash?

Backlash compensation is where if there is play in a ballscrew you can compensate on axis direction change to take up the slack before the motion is registered. In my opinion backlash adjustment is a waste of time on machines such as a mill because the tool will pull the axis around and backlash compensation cant stop that, much better to sort the backlash mechanically.


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6) Ok. i have been looking at this card. Just so i have got everything right. I take the USB from my computer to the SS card and from that card over to the brakeout card right? Will the SS card and drive on my computer need more CPU power or it don't need more power to get this high frequency?

Yes thats correct, Computer USB to SS to Breakouts to machine.
 The SS should actually allow you to use a less powerful computer as it takes the pulseing away from the computer and does it externally.  However I still recommend that you go with a computer that meets the minimum specs for Mach.


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7) But i can also use A / B  pulse train for the position wheel and connect to my brakeout card?

Yes you connect them to Inputs and set up in Mach for MPG

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8 ) Do you connect your drives to the mach 3 so you can se the position?

Not really sure what you mean here. I have my drives fault signal connected to Mach so that they would inform Mach they have faulted and Mach would stop execution of code and go into reset.

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(9) Ok. But then i will have to put the analog inputs to my plc? Do the breakout bord have analog inputs for this?

No breakout boards dont have analogue inputs, or at least none that I can think of. You could use a PoKeys to do that but it only has 0 to 3.3v analogue so your drive would need to be able to scale the analogue signal to that which is unlikeley. If using a PLC you will need to use one that is capable of ModBUS, the DL06 from Automation Direct is the one most people here use.

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10 ) Do you have any gearbox then on your mill?

 My mill does have a backgear gearbox but I intent not to use it. Previous to me fitting the servo on the lathes spindle it had a normal induction motor and this was driven through a gearbox. The gearbox had electromagnetic clutches which could be changed to give various speeds, I controlled that via the PLC and a spindle speed macro in Mach. I have since done away with that and fitted the AC Servo which gives me infinite speed control from 0 to 2000rpm, the original setup had 16 speeds.

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It seems like you are using this alot, What kind of servodrives do you use in your machines?

I use Allen Bradley DSD drives

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All things like tool data and so on are supported by the software?
Not really sure what you are meaning here but if you are meaning a tooltable with length and dia offsets then yes, there are tool offsets available

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Is it possible to have one home position with the switches on my mill and then have more zero points, Like if i put up my work piece and make X, Y and Z zero to that piece? I hope you understand what i mean.

You can set 253 different offsets and call them via G54 to G58 and G59P7 TO G59P253

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Do you have an postprocessor on the outside were you make all your G-Codes?

A lot of CAM software already has Post Processors for Mach, you can also use the wizards within Mach for doing simple stuff like Bolt Circle, Pockets (circular and square/rectangular) and a lot more. You can also purchase an addons package from NewFangled solutions which will allow you to chain a lot of different things such as pockets, circles, bolt holes etc and produce code for a completed part, all depends on how complex your work will be whether you will need a CAM package or not.
Hood

Thanks for your fast replays...


3) Yes you will need to home on every restart but really you would need to do that in anycase whether you had absolute or incremental as Mach itself is open loop.

Ok, then it were as i tought it would work.

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5) Backlash compensation is where if there is play in a ballscrew you can compensate on axis direction change to take up the slack before the motion is registered. In my opinion backlash adjustment is a waste of time on machines such as a mill because the tool will pull the axis around and backlash compensation cant stop that, much better to sort the backlash mechanically.

Ok. today my DC servo drives have tooth belts from the motor to the ball screw. I have plans to change them to planet gearbox instead. But can the old parallelport handle backlash compensation?

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6) Yes thats correct, Computer USB to SS to Breakouts to machine.
 The SS should actually allow you to use a less powerful computer as it takes the pulseing away from the computer and does it externally.  However I still recommend that you go with a computer that meets the minimum specs for Mach.?

Yes i understand that. i just wounder if this need system would need more cpu power. What kind of computer do you use for your machines? do you have one computer for every machine?

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7) Yes you connect them to Inputs and set up in Mach for MPG ?

Great. thanks.

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8 ) Not really sure what you mean here. I have my drives fault signal connected to Mach so that they would inform Mach they have faulted and Mach would stop execution of code and go into reset.?

I did mean if you have connect an pulse train out from your drives and into the mach or you dont do that? I do understand that with the fault signal. Do you have one fault input from every drive or all fault signals in one serie?

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(9) No breakout boards dont have analogue inputs, or at least none that I can think of. You could use a PoKeys to do that but it only has 0 to 3.3v analogue so your drive would need to be able to scale the analogue signal to that which is unlikeley. If using a PLC you will need to use one that is capable of ModBUS, the DL06 from Automation Direct is the one most people here use.?

Ok. I have alot of Omron plc systems and i can communicate modbus with them, that is no problem at all. So then it will be possible to get the signals into the mach system? Do you know if the Mach 3 graphic interface has meters for spindle and axis power?

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10 )  My mill does have a backgear gearbox but I intent not to use it. Previous to me fitting the servo on the lathes spindle it had a normal induction motor and this was driven through a gearbox. The gearbox had electromagnetic clutches which could be changed to give various speeds, I controlled that via the PLC and a spindle speed macro in Mach. I have since done away with that and fitted the AC Servo which gives me infinite speed control from 0 to 2000rpm, the original setup had 16 speeds.?

Ok. but on your mill, do you still have your gearbox left or you have taken that away?

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I use Allen Bradley DSD drives?

Ok. and then you also use Allen Bradley motors right?

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Not really sure what you are meaning here but if you are meaning a tooltable with length and dia offsets then yes, there are tool offsets available?

Im not so good in english yet, but that was exactly what i meant. How many tools? Will there come up on the screen when the machine would like to change tool then? Will the machine go out to a specified point in X,Y and Z when i change tool?

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You can set 253 different offsets and call them via G54 to G58 and G59P7 TO G59P253?

That sounds good.

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A lot of CAM software already has Post Processors for Mach, you can also use the wizards within Mach for doing simple stuff like Bolt Circle, Pockets (circular and square/rectangular) and a lot more. You can also purchase an addons package from NewFangled solutions which will allow you to chain a lot of different things such as pockets, circles, bolt holes etc and produce code for a completed part, all depends on how complex your work will be whether you will need a CAM package or not.?

- I do all my work in Solidworks today and i also have Edge cam, an older version but with 3D so i think i will use this one.



- Is it possible to make my own mach 3 "skin" Layout or whay you call it for my interface on my machine?

- What kind of PC display do you use for your applications? do you have touch screens? Size?

Best Regards
Oscar Larsson



[/quote]

Offline Hood

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Thanks for your fast replays...

Ok. today my DC servo drives have tooth belts from the motor to the ball screw. I have plans to change them to planet gearbox instead. But can the old parallelport handle backlash compensation?
Yes It can. how good it is I cant say personally as I have never used it.

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Yes i understand that. i just wounder if this need system would need more cpu power. What kind of computer do you use for your machines? do you have one computer for every machine?

I use a Via Pico in each machine http://linitx.com/viewproduct.php?prodid=11693


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I did mean if you have connect an pulse train out from your drives and into the mach or you dont do that? I do understand that with the fault signal. Do you have one fault input from every drive or all fault signals in one serie?

I have all the fault signals connected in series relays.

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Ok. I have alot of Omron plc systems and i can communicate modbus with them, that is no problem at all. So then it will be possible to get the signals into the mach system? Do you know if the Mach 3 graphic interface has meters for spindle and axis power?

No but you can make your own screen or graphics to suit yourself, there is a utility for Mach called Screen4 which allows you to do things like that. You also can use macropump or a Brain too get the info into the DRO (or meter as you would see it in this instance)

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Ok. but on your mill, do you still have your gearbox left or you have taken that away?

At the moment it is still there

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Ok. and then you also use Allen Bradley motors right?

Mostly but have some others, Indramat being one type I used. I had to remove the resolver and replace with an encoder for my drives.


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Im not so good in english yet, but that was exactly what i meant. How many tools? Will there come up on the screen when the machine would like to change tool then? Will the machine go out to a specified point in X,Y and Z when i change tool?

253 tools, could be 254 not sure never really needed that many ;)
You can write macros to do almost anything you want with regards to toolchange


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- Is it possible to make my own mach 3 "skin" Layout or whay you call it for my interface on my machine?

- What kind of PC display do you use for your applications? do you have touch screens? Size?

Best Regards
Oscar Larsson

Yes as mentioned above you can make a screen to suit your own needs with Screen4

I have 17inch touch screens on my machines.

Hood

Yes It can. how good it is I cant say personally as I have never used it.

Ok i understand that.

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I use a Via Pico in each machine http://linitx.com/viewproduct.php?prodid=11693

Is this good enough? Did not seem to be so fast? Is it just ram memory i need to buy to that system to get it complete?


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I have all the fault signals connected in series relays.
So the Mach 3 / brakeoutbord has only one alarm input then?

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No but you can make your own screen or graphics to suit yourself, there is a utility for Mach called Screen4 which allows you to do things like that. You also can use macropump or a Brain too get the info into the DRO (or meter as you would see it in this instance)
Sound great ;D

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At the moment it is still there
Ok but have you then put the gearbox in the highest gear? So you control the speed from the mach instead?

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Mostly but have some others, Indramat being one type I used. I had to remove the resolver and replace with an encoder for my drives.

Why did it not work with resolver? Have you seen any diffrence in using Allen bradley against Indramat? or the diffrence is to small to be seen?


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253 tools, could be 254 not sure never really needed that many ;)
You can write macros to do almost anything you want with regards to toolchange
This sounds really great.

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Yes as mentioned above you can make a screen to suit your own needs with Screen4

I have 17inch touch screens on my machines.

Great. What kind of display do you use, brand?

- What kind of work do you make with your Mill? Do you make 3D milling?
- I just wounder if you have been using other systems before like Siemens, Fanuc, Heidenhein or something like that and can say if you belive the Mach 3 can make the same end result on the work piece?
- Do you mill work pieces with high finish and high tolerance and belive the system handles it good?

- How have you make your installations. Have you placed the brakeoutboard and the SS card in the cabinet with the Servo drives or you have them together with the computer?



Best Regards
Oscar Larsson

Offline Hood

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Is this good enough? Did not seem to be so fast? Is it just ram memory i need to buy to that system to get it complete?

It is surprisingly fast even though it is just a 1Gig CPU. You will need the ram, a hard drive and a power supply, I just use a normal ATX power supply.


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So the Mach 3 / brakeoutbord has only one alarm input then?
There is only Input 1 in Mach that can be dedicated to be used as a fault signal. You can however use any amount of inputs you wish to do almost anything you wish, what you would do is have a Brain or the Macropump monitor them and do what you require.

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Ok but have you then put the gearbox in the highest gear? So you control the speed from the mach instead?
I do have it in the highest gear at the moment, it is not completed yet,  I dont think I will need the backgear but I am just keeping it there in case I do. There are spindle pulley ratios that you can configure in Mach and although I have never had cause to use them I think they would make two or more gear ranges possible.

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Why did it not work with resolver? Have you seen any diffrence in using Allen bradley against Indramat? or the diffrence is to small to be seen?


The drives I use only support encoders. It works every bit as well as the AB motors as I have the commutation signals on the encoder lined up correctly and also the AB drive software has a utility that you can use to configure custom motors.

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Great. What kind of display do you use, brand?
They are various brands of TFT and I have added touch panels which are readily available on eBay.

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What kind of work do you make with your Mill? Do you make 3D milling?
My work mainly consists of repair and fitting of fishing boats so mostly one off stuff. It is all 2.5D stuff, I dont do any 3d work unless thread milling could be classed as that? There is no reason that 3D work could not be done and the quality would depend on the machine resolution and rigidity rather than Mach.

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I just wounder if you have been using other systems before like Siemens, Fanuc, Heidenhein or something like that and can say if you belive the Mach 3 can make the same end result on the work piece?

No I have never use anything else unless you call being a button pusher on a Heidennhain control mill for a few days using one ;)
 Again if the condition of the machine is similar then I believe Mach can produce work as good as any other control but that is just my opinion.
-

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Do you mill work pieces with high finish and high tolerance and belive the system handles it good?
Again that is a function of the machine, my Bridgeport mill in my opinion is not a very rigid machine but it will put out the same quality of work as it would if it had any other control on it. My Lathe is much more rigid and extremely accurate, I have the servo drives set to fault out at a 20 count following error out of 8000 per revolution and 5mm travel per rev so if the axis was out by 0.0125mm it would fault, I have never had that happen yet.

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How have you make your installations. Have you placed the brakeoutboard and the SS card in the cabinet with the Servo drives or you have them together with the computer?

Below are pics of the Beaver Mill and Computurn lathe cabinets.

Hood
Hello Hood.

That sound great.

On the first picture you have this big green card in the middle of the cabinet, what is that for?
And also on the right you have 2 cards with some big relays on, what is that for?

Yesterday i spent my day to redaing about interface and designing them and i came to think if its possible to design an layout like the onces below.
And also if i can make my own popup menus and so on? Were is the limit in designing?
I already have all the pictures.

Best Regards
Oscar Larsson

Offline Hood

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The big card in the middle is  a CNC Building Blocks Acustep breakout board, unfortunately Ed no longer makjes them. The reason I used them was to give me Index pulse homing however I now do that internally in my drives. Another feature of the breakout is that it puts out differential Step/Dir signals which is obviously better for noise immunity and preferred over single ended signals on the drives I use. This could be done with a line driver if needed.
 
 The relays are used to convert the outputs from Mach to 24V for things such as contactors, coolant etc

You could do a screen like you have shown although one thing I know you cant have is horizontal sliders for FRO etc, Screen4 only has vertical sliders. Pop up menus are not possible as far as I know although you can go to full pages if that would be any use.
 If you know anything about Flash then you could make up a screen in that and from what I have seen do almost anything you want, I think popups would be no problem in Flash.
Hood