Bridgeport Retrofit motion control?

[gavztheouch]

I know that mach 3 has a large following and many people use it successfully all day everyday including myself. However, in my experience you can get mach to work quite well very quickly, but I don't have a great deal of faith in it in an industrial environment, probably because it was never intended for that purpose, hence the promise of a mach 4 industrial version. I like the look of mach 4, but don't believe its quite ready yet.

Don't get me wrong, there are some amazing machines using mach such as Hood's and many others and I'm almost tempted to get hold of a smooth stepper and jump right in, but in the back of my mind I know I'll be disappointed. Has anyone got any experience of an MPG that works well in mach 3? when I've tested it it was horrendous to use and wouldn't trust it at all!

Mach 3 works best with a motion controller like a Kflop. If I understand it correctly a motion controller actually does the majority of the work and mach3 almost acts like a fancy interface?

[drumsticksplinter]

Hi Sam,

Thanks for the info, I've toyed with the idea of linux in the past, but only got as far as loading the demo operating system off a disk. Other than that I have no idea about it. I've seen other people using the mesa cards and they certainly are cheap for what you get. What combination of card and daughterboard would you recommend?

Say if I were to set up linux for the first time without any previous experience and little to no programming experience, how quickly could I have stuff moving around? I'd like to build a custom control panel with MPG FRO and spindle speed over ride etc, are these easy to implement in linux cnc?

You've got me thinking now.... I'm also finishing off a router at the same time, so if I could crack linux on my mill then I'd use it for that also

Thanks,

Adam.

[skunkworks]

what is your hardware now? analog servos? Step/dir? Mesa has a 5i25 or 6i25 (pci or pci-e) that right out of the box acts like 2 printer ports on steroids. (so you could use your existing bobs if you are using printer ports) On steriod - I mean it does hardware (high speed) step/gen, pwm gen, encoder counting, and i/o. ie - well into the mhz..

if you need more i/o than 2 printer ports - you can get daughter boards like the 7i76 that is a stepper interface. (gives you 5 axis step/dir output, analog spindle output, 48 i/o, spindle encoder input - and still expandable)

you can buy it as a kit..
http://store.mesanet.com/index.php?r...product_id=215

linuxcnc has a configuration utillity for mesa hardware - I have never used it but it is constantly being improved.
http://linuxcnc.org/docs/2.6/html/config/pncconf.html
main docs
http://linuxcnc.org/docs/2.6/html/

do some reading....

sam

Hi Sam,

Thanks for the info, I've toyed with the idea of linux in the past, but only got as far as loading the demo operating system off a disk. Other than that I have no idea about it. I've seen other people using the mesa cards and they certainly are cheap for what you get. What combination of card and daughterboard would you recommend?

Say if I were to set up linux for the first time without any previous experience and little to no programming experience, how quickly could I have stuff moving around? I'd like to build a custom control panel with MPG FRO and spindle speed over ride etc, are these easy to implement in linux cnc?

You've got me thinking now.... I'm also finishing off a router at the same time, so if I could crack linux on my mill then I'd use it for that also

Thanks,

Adam.

[Clive S]

drumsticksplinter ] You can also buy them here in Europe http://eusurplus.com/index.php?route...tegory&path=63.

Sam I would like to ask you some questions re threading with G76 could I do it with email to you. ...Clive

[JAZZCNC]

However, in my experience you can get mach to work quite well very quickly, but I don't have a great deal of faith in it in an industrial environment, probably because it was never intended for that purpose, hence the promise of a mach 4 industrial version. I like the look of mach 4, but don't believe its quite ready yet.

Correct But Why anyone would expect a £130 Control software using windows parallel port to be industrial strength is beyond me if I'm honest.!! . . . . Your simply being unrealistic in your expectations.!

Now while Mach was never intended for industrial control that was using the Parallel port.!! Windows and parallel port we all know are rubbish for anything but simple hobby use but Mach works like a Charm with a Quality Motion control Card Like Cslabs or Kflop, Galil etc

Without getting into the Linux vs Mach rubbish both softwares do a great job for very little to No money in Linux case and when correctly matched with Hardware can give some of the very very expensive industrial controls a very good run for there money but unfortunatly all to often People are too quick to fire and blame the software. Often it really is case of " Poor workman blaming is tools". .!!

[Boyan Silyavski]

At the link Clive provided they have the C23 dual LPT BOB for only 72eur, surplus. Big, cheap and reliable, did i say big :-) .

Thanks for pointing to that shop, i have been searching for something like that some time.

[skunkworks]

That bob is huge!

I (being biased) still think for being under 200 euros the 5i25+7i76 gives you a lot more flexibility. The daughter board gives you..

The 7I76 is daughtercard/breakout board for use with MESA's 25 pin I/O FPGA cards like the 5I25. The 7I76 is designed for interfacing up to 5 Axis of step & dir step motor or servo motor drives and also provides a spindle encoder interface, isolated analog spindle speed control and 48 isolated I/O points for general purpose field I/O use. All step and direction outputs are buffered 5V signals that can drive 24 mA. All outputs support differential mode to reduce susceptibility to noise. An isolated analog spindle voltage with direction and enable outputs is provided for spindle control as is a single spindle encoder channel with TTL or differential inputs. 48 points of isolated field I/O are provided for general control use including limit switch and control panel inputs, coolant enable and tool changer control outputs. Isolated I/O includes 32 sinking inputs and 16 sourcing outputs. Inputs can sense 5V to 32V signals and the outputs can switch 5V through 28V signals. Maximum output load is 300 mA. Outputs are short circuit protected. In addition to the being able to read digital on/off status of each input, four input pin voltages are readable with 8 bit resolution, and two MPG encoder inputs are provided as an option on four field inputs. Field I/O is powered by an isolated 10-32V field power source. One RS-422 interface is provided for I/O expansion via a serial I/O daughtercard. All field wiring is terminated in pluggable 3.5 mm screw terminal blocks.

Plus it is expandable be it the 2nd port on the 5i25 or the smart serial port on the 7i76. (not to mention if you want to go full closed loop servo the 7i77 daughter board is for you)

Did I mention that I love mesa hardware? It is well built and 'just works' tm

Other similar solutions are going to be more money like ESS+C23.. (plus - who wants to rigid tap? :) )

most have seen this - linuxcnc + mesa (my conversion of old K&T HMC) 4 axis + 96 i/o (full closed loop) Still running great.

https://www.youtube.com/watch?v=39q6kvrSBSk

sam

[drumsticksplinter]

Correct But Why anyone would expect a £130 Control software using windows parallel port to be industrial strength is beyond me if I'm honest.!! . . . . Your simply being unrealistic in your expectations.!

I think you misunderstand, I'm not expecting the parallel port and mach3 configuration to be industrial strength because it obviously isn't. Conveniently though using a breakout board and parallel port provides a very quick and cheap means of testing the bare bones of a machine build and thats all I'd use it for.

I'm just looking for a good stable solution to a motion control system on my machine. The thing that has really put me off mach3 is the MPG feature, which is what i really want to work well, I've tested it with a pokeys board, which claimed to offer the feature, but the results were terrible. I've read about other people having serious issues with the MPG feature in mach3 too. No matter how much I ask about the functionality of mach3 with and MPG, nobody seems to be forthcoming with information, why is that? Because it doesn't work? Artsoft have said as much, thats why part of their selling point for mach 4 is "Higher quality manual pulse generator (MPG) = very smooth jogging and positioning without lag time.".

I was wondering if the MPG feature worked well with the ESS or CSlabs?

[komatias]

...Because it doesn't work? Artsoft have said as much, thats why part of their selling point for mach 4 is "Higher quality manual pulse generator (MPG) = very smooth jogging and positioning without lag time.".

I was wondering if the MPG feature worked well with the ESS or CSlabs?

Agreed to some extent. Linking the MPG directly to the LPT or other motion control many not yield totally reliable results. but then you can always go with the Vistacnc stuff like:




I will be evaluating this for my own purposes.

[drumsticksplinter]

but then you can always go with the Vistacnc stuff

I've admired the vistacnc pendants for a while now but haven't got round to ordering one to try. I'd be interested to see how they perform, though I wouldn't be surprised if it was something like the pokeys inside with a fancy plugin written around it....