BRX vs Mach3

[Garyhlucas]

I frequent the Mach3 CNC software forum.  You would be amazed at how many messages pop up about trying to use Mach 3 to control some kind of machine with a little bit of motion.  They have a used PC and a chinese breakout board and they want to do stuff that is easy in a PLC but simply not possible in Mach 3 or 4 without lots of time kludging it all together. I keep pointing them to the BRX now, hope you see some business from it.

We just got POs for 3 more systems with a BRX and a little more than $10K of AD stuff in each one.  Year is shaping up well.

[DannyB]

I posted the programs i use to control a WinCNC based CNC using a BRX at https://github.com/dberlin/CNC-PLC
It handles all the safety sensors from the spindle, the VFDs, the vacuum pump, etc.

Nowadays most of my controls are being done over ethernet/ip (i hate tons of cables) and i moved from analog spindle speed to PWM, but if you look in the history there are versions that do things the "more standard" way.

It's actually safer/better than the original machine PLC, as this one can properly high speed count the spindle revolution sensor, and so knows what speed the spindle is currently at for real, so it knows when it is up to the command speed, etc (instead of whether it's just spinning or not).

The one thing i miss is cyclic messaging in ethernet/ip

[BobO]

That's awesome! Thanks!

By cyclic messaging, I assume you mean implicit? We wrote our own interface for explicit, and were warned by those with experience that we didn't want to tackle implicit. I really wish we had it, and may revisit that when we finish a few more projects.

[pbw]

I posted the programs i use to control a WinCNC based CNC using a BRX at https://github.com/dberlin/CNC-PLC

I'm curious what type of machine you are controlling?Mill,Lathe,Plasma Cutter? would love to get into CNC if time would permit it.

[DannyB]

That's awesome! Thanks!

By cyclic messaging, I assume you mean implicit? We wrote our own interface for explicit, and were warned by those with experience that we didn't want to tackle implicit. I really wish we had it, and may revisit that when we finish a few more projects.

Yeah, i mean implicit messaging.

Having known folks who did it, it is a pain in the ass, but that's because it actually requires sane and careful programming to get right, which tends to be in short supply in embedded systems (I used to work on compilers and debuggers for everything from video game consoles to you name it).

[DannyB]

I posted the programs i use to control a WinCNC based CNC using a BRX at https://github.com/dberlin/CNC-PLC

I'm curious what type of machine you are controlling?Mill,Lathe,Plasma Cutter? would love to get into CNC if time would permit it.

This is a Mill. I'm not driving the servos with the BRX, that's handled by a motion controller card

It used to be for DIY you had to use Mach or if you wanted to get expensive, WinCNC, but Centroid (a long time player in the CNC market) now has a DIY line which is really nice, and has a very reasonable low end (acorn) and high end (oak).
A lot of folks are starting to pick it up as a great alternative to mach.
(From what i know, it just works with no real futzing and bs)