Machsupport Forum
Mach Discussion => General Mach Discussion => Topic started by: NJC on March 30, 2008, 08:01:00 PM
-
Hello all, this is my first post! I have an older Bridgeport that is running with a Prototrak MX# 3 axis CNC setup. Works pretty well for how out of date it is, performs simple tasks easily. Problem is I have to program every event and it's eating time like nobody's business! I need the ability to import G code from V-carve pro or other tool path makers. I have been successful so far with the demo versions of both Mach 3 and V-carve. I'm looking to upgrade the system to a new up to date system. I'm thinking after much research that I will be using Mach 3 on my PC to control it, I downloaded the demo and I'm very impressed. Mach 3 does way more than I will probable ever use but it's nice that it's all there. I need to know what else I will need to complete the transformation, I have all the motors and such, they are fairly new and work well. I'm reading allot about motor drivers, boards, controllers etc, it all is new to me and I'm a little confused. I must have a motor driver or drivers now to run what I have, could these possibly still work with Mach 3? Thanks in advance for the help!
-
Welcome to the Forum!
If you have motors already, you probably already have drives & a power supply. Tell us more about your drivers (brand/model)
Assuming the drives accept step/dir input signal the other items you would need (if you don't have them) is a breakout board to interface your PC with the drives- Home/Limit switches, an E-stop button, depending on the type/brand/model of Breakout Board you might want/need to get a couple of relays to start your spindle and/or coolant. I use the shuttlepro pendant controller, although there are a lot of choice available for pendants. I think that's about it- you should be good to go.
Good Luck!
Sid
-
OK, my motors are Magnetek model # 4020d-155, they say 1/3 HP, 2200RPM, V arm- 160, A arm- 2.97, I'm going top try to post a picture of inside of the motor end cap, it has a circuit board in there with alot of wires, maybe this board can be removed and wired directly? I'm not even sure of which parts are the drivers, there is a ton of stuff in the system, it looks very complicated, too complicated for my electronic knowledge to deal with honestly. I will try to post some pictures of the rest of the system as well, maybe someone can make some sense of it. If I have to buy new motors and drivers as well, I will, I just don't want to unless I have to.
-
Shoot, the pictures are probably too large, does anybody know how to center the pictures or make them smaller?
-
Hey NJC, You can resize those in almost any photo edit program.
Brett
-
I got my hand slapped the other week - you need to re-size your pictures to 800 x 600 pixels - any of the cheap picture editing programs will bo it.
If not, download a freeware version from the internet.
Before you can get good advice, you really need to make your own mind up about what result you want to see.
My own system is as simple as it gets. A lathe/mill driven by home installed stepper motors. No measuring device or feedback, I don't bother with limit switches. My speeds are very modest. ( That said, it does the job - and I can keep my eye on it when I am running)
I am quite sure - in fact I know - that other contributors have very fast moving, large machines, they need all the safeties (and in an industrial set-up they are probably mandatory) ;D
I am familiar with Bridgeport mills - and the older ones tend to be large, slowmoving machines - very accurate etc. is it for industrial use, or the home workshop environment.
You have probably read the Mach 3 stuff over and over again, so you will know what Mach 3 can do. I would suggest that, for ease of use, you hold on until the Smooth Stepper is available ( coming soon from an outlet near you ;D), because the lads that have tried the pre production stuff say it is the bees knees. I anticipate - although I have not seen one, that this will give all the inputs and outputs necessary (and a few more besides) to wire to your lathe/mill in any configuration you want, and the only connection to your computer will be a USB lead - rather than having to mess about with the old LPT1 lead and a breakout board (which is limited and then you need other boards etc etc)
In the meantime, I would suggest you contact the makers of the motors, you say they are nearly new, and ask them what drivers and power supply systems (and more important, control systems) they recommend for them. They made them, they should know, and quite frankly, they are nothing to do with Mach3 (I don't mean that rudely). They are a bit of the machine - and that varies in all our different applications. As "Ssheidenr" said - if they are working now, something must drive them - and if they are CNC already, that probably Mach can deal with them.
If they are steppers - fine, I know about them, but I know nothing about servo motors and linear feedback instruments. The thing I do know is that Mach can deal with both easily (and does).
The spindle can be dealt with equally simply - I had to install a new three phase motor, but after that a commercial (Omron) inverter solved my control problem and Mach 3 was able to interface with that simply and easily. You might find that an inverter ( you may already have one) is fitted and you can connect speed control from Mach to your machine without any further interface.
As I say - I think the answer is up to you - how do you see it progressing.
After that, anything we can do to help.
-
Thanks for the input Jim, I want my machine to run as fast as possible and I'm not afraid to spend some money on the upgrade. I have glass sensors on the machine for inputs and motors on the machine to make ot move, I just need a better way to move the motors. If it would be better to replace my motors with stepper motors, I would do that, the cost is not as important as the outcome, I want to do this one time and do it as best that can be done. I think Mach is the way for me, I have purchased the software licence already and have been working with the software to get farmiliar with it. I'm not new to cnc at all, in fact I run my machine everyday creating lots of different stuff. I have been reading on the "Smooth Stepper", I guess this is the way to go, if it is USB driven, does that meen that the connections will be easier? I would think that I would be quite a bit faster processing as well. How soon will these be available? weeks, months
Scott
-
Sorry for the large pictures guys, I'm new to this forum and still learning. I removed the old ones, try these, let me know what you think of these motors, would these be servo motors?
-
Ahhh, I got it now, this is a picture of inside my control panel, it's an older Prototrak MX3 setup
-
And finally, picture of my sensors
-
Honestly, it's a little hard to tell but, if someone was putting a gun to my head, I would say, "Yes, those are Servos". Steppers typically have 4, 6 or 8 wires to drive them. Seems like you have more than that inside that 'cozy bundle'. Plus it seems like there is some kind of PCB board in there which I would venture to guess is your Encoder output.
HTH,
Sid
-
Going by the pic of the motor it looks like they are brushed DC servos. Not sure what that is inside as you say you have glass scales then I would have thought an encoder wasnt needed so it could be some form of Tach although Tachs usually dont look anything like that.
I tried doing a quick search for the motors but cam up a blank but from your specs it seems they are 160V 2.97Amp. I would imagine your drives to be analogue input so you probably wont be able to use them with Mach unless you get an Step/Dir to Analogue converter. You could probably drive these motors with Geckos, Tek10s etc but your top speed would be reduced due to the voltage these drives can handle. There are drives from Rutex that have higher voltage which might be suitable but I have no experience af them.
Firs thing you really need to do is try and find out from the motor manufacturer as much as you can, also try to find out about your drives, make, model etc.
Hood
-
Thanks, I will check with the motor manufacturer for the exact specs and repost them. In the meentime, on the fisrt page of this thread, last picture, this seems to be one the coordinate sensors, there is one on each axis, do these look like glass scales or something different? If so, are glass scales the best to use or should I be considering something else? Do the "Stepper Motors" have a position sensor on them?
Scott
-
Yes they look like glass scales (linear encoders) You could probably use them if they put out TTL with A and B chanels. If not then it would be no hardship to get rotary encoders and fit them to your motors. Your motors may have encoders already and the scales are used as a comparison but I doubt it.
You have servos by the looks of it, the encoders tell the servo drives the position. You may have tachs on your motors which detect speed of the motors but you dont need them with mach.
Glass scales are accurate but if you have any play at all in the machine it can cause problems, often it is better to have the encoders directly on the motors.
Hood
-
I dont think they are steppers either.
Whatever type of motor you have, basically Mach3 puts out two signals for each axis. One is a step pulse, and the other is a dir pulse. Both - coming from the computer either via LPT1 printer port output, or the new smooth stepper USB output, are at 5 volts.
If, in the end, you decide to replace your motors, then, if you pick stepper motors, you will find that the drives will operate directly from the computer signals. You merely put in a drive voltage from your power supply, and connect up your motors. If you then input the two signal wires (three with the signal return line) to the step and dir inputs, the motors will drive, It is that simple.
I might be preaching to the converted here if you are used to CNC.
Although you can use feedback from measuring instruments to confirm Mach3's position, it does not need any. Mach3 keeps a record of it's own position through the program by counting the number of step pulses it puts out - the only problem is if (for some reason) your motors miss steps. This is usually caused by trying to get too much speed or acceleration on G0 moves - but all in all it is accurate, and if you run well within the limits of your machine, it will be accurate.
-
Hey Jim, no I'm not converted, I appreciate all of ythe input you guys have given. I'm no expert, just have some cnc machine experience. I'm finally starting to get how the whole cnc thing works, it's pretty involved, more than I thought. I put my name on the list for a "Smooth Stepper" and I have purchased the Lic for Mach 3, so I guess I'm on the way. I'm not having much luck finding info on the motors that I have and even if I do, I still have to wire them to the new system and I don't have any wiring diagram. Also the circuit board that is in the motor end cap, I have no clue what it is and it was installed by the company that provided the retrofit kit, (it has their logo on it). I think it would be best, especially if my system will be slow with the servos to replace them and the rest of the drivers, boards, ect. Does anybody have a suggestion for stepper motor size, oz, voltage, amps, ect? They will have to be fairly large to run a bridgeport I would think.
Scott
-
If you want fast then you want to go servos. I have steppers on my Bridgeport Mill and get 2500mm/min but on the new mill I have servos and theoretically I could get 20,000m/min
Steppers are good for smaller machines but as you get up in size servos are the way to go.
Hood
-
Hood, I thought you were saying in a previous post that it would run slower with servos, I guess you were refering to the drivers? Wow, I'm glad to hear that, I just found a schematic of my system, well some of it, it doesn't go into too much detail. You were right when you said the motors looked like they had encoders, they do and the glass scales are for back up. Apperently, the glass scales were an option with the retrofit. The schematic shows the E stop and limit switches as well. This is looking better and better, just a matter of figuring out the details. Is the "Smooth Stepper" still the best option with servos?
Scott
-
Is the "Smooth Stepper" still the best option with servos?
Yes. You'll love it.
One thing, is it deffinatly glass scales? Not by chance a cover for limit switches is it? Reason I ask, I got fooled on the Hurco a while back. Thought for sure it was glass scales. the way they had those switches in there was nice. :)
Brett
-
Yes what I was meaning was if your motors are higher voltage that was common on the older DC servos and you ran them from lower voltage drives then your rapid speed would be reduced accordingly. If you can find out what voltage your motors are or even what the power supply transformer puts out then we can go from there. Also have a close look at your drives to see what inputs they have, there is a slight chance they may accept step/dir.
As Brett says the SmoothStepper would be a good option for you, especially if yous encoders have a high count.
Hood
-
Scott - The clique that is testing the "smooth stepper" is keeping everything close to the chest.
As far as I understand it, all it is is a USB version of the LPT1 printer port.
When Mach3 started, the system to connect the computer to the machine was a printer port cable. This was satisfactory, it had the necessary speed and all computers had one. To be fair, it's cheap and it works well - I am still using mine - because my system is simple.
The big problem with it is the lack of pins (outputs and inputs). There are 8 outputs (mainly to drive the axis - 2 wires per axis), another 4 outputs (mainly for coolant, spindle motor on off and reverse) and 5 inputs. The inputs are a problem. If you want limit switches, home switches, spindle speed reader, and feedback from any measuring device you have on your machine (like servo motors) then there is just not enough input via the LPT1 port.
You could get additional printer ports, but modern computers are now coming out without the old 25 pin printer ports and doing everything via USB.
I understand the "smooth stepper" is just that - a collectionof input and output ports to connect to your machine - and all you do is plug in a USB lead. I understand there is also some sort of driver chip (s) on it, so whereas before your computer generated all the pulses necessary to drive your machine, now the smooth stepper does a lot of the work. This means that the type of computer is less demanding - many of us like laptops in the workshop (but some of these had problems). Smooth stepper will apparently work with any computer that can run USB ( I assume USB 2")
Thats my bit - no doubt I will get shot down in flames if the info is wrong - but as yet I've got to see a spec - come on guys - let us into the secret.
-
There is info about the SmoothStepper on this forum and also Gregs own forum.
http://www.machsupport.com/forum/index.php/board,65.0.html and
http://www.warp9td.com
Basically the SmoothStepper does away with the need for a computer with a parallel port, it also basically has the pinouts of two parallel ports and also has additional inputs for encoders or MPGs. The normal way of setting up motors and all other I/O will be the same, ie you still use ports and pins and still use the Port column for defining which port they are on.
The SmoothStepper does the pulsing and as was said this does away for the need of a software pulse engine, leaving Mach to concentrate on the calculations. The pulse rate is at 4MHz max at the moment where the Parasllel Port is 100KHz, thats a 40 fold increase. Also even at 4MHz the pulse is super smooth :)
I have run the smooth stepper through the Pico motherboard that I am using on my milling machine that I am in the process of retrofitting. This Pico motherboard is tiny (100mm X 72mm), has a 1GHz embedded CPU and up to 1GHz of memory, onboard graphics, LAN, Serial, 4x USB and PS2 for mouse and keyboard. I tried running Machs Driver Test on this board and it wouldnt run, just locked the pico up, however with the smoothStepper it works perfectly, I have not had it running my new mill as its not ready, so I couldnt test at the speeds I will be running the new mill at. However I did have it hooked to my old mill and it ran it perfectly at the feedrate of the 3D programme which was 1000mm/min. see here http://www.youtube.com/watch?v=bApuwkkXTb8
There is word of addon boards for the smoothStepper that will add to the I/O but not sure what or when.
Hood
-
Oh and BTW to let you know how good I think the SS is, I have ordered 2 for myself in addition to the Beta one I already have :)
Hood
-
I've seen your youtube video and a few others, pretty cool! All sounds great, I can't wait to get it all set up.
-
OK, I found some more info. The motors are DC servos that are fed with 115 volts. They also have a servo amplifier on each servo. I will upload a diagram of the motor and servo combination. I also found a partial diagram of the main wiring from the manufacturer, I believe the L1, L2 ans L3 are the limit switches and it shows the E-stop. I emailed the company that created the retrofit to see if I could get the wiring schematic for the boards and such, they said they could make a set for me for $70.00 that would NOT include the servo amplifiers, they say they are proprietary, I guess that meens they won't give that info out. My questions are, will the smooth stepper work well with the servos I have? Would having the wiring schematics without the amplifiers be sufficient for me to set this up? What is a servo amplifier and what does it do? Do they make the motor work faster?
-
Here is a diagram of the back of my control enclosure, note the listing of the encoders, limit switches, e-stop. Also at the bottom it says the amplifiers are digital and the servos are 280 oz and that is is a closed loop system using the encoders, Does all of this sound like it will be compatible?
-
Amplifiers are the Servo drives, its just another name for them.
The Smooth Stepper is basically just a replacement interface for the parallel port, it uses the USB and allows you to connect all the I/O that you would manage with 2 paralell ports. It also has the advantage of having the pulses preduced on it rather than the software pulse engine. This allows much faster/smoother pulse rates and will allow the use of almost any computer, even those that gave problems in the past like laptops.
However it will not allow you to use your servo drives if they do not accept step and direction, so if that is the case you will need to either get a Step/Dir to analogue converter for each drive or get new drives or stick with what you have.
Hood
-
I think Hood has put the problem simply - I assume the equipment you have got, when it is all put together, will drive your motors - and hence the mill.
Mach3 is NOT a DRIVER - it is a controller - so the question is, when you get it all together - what makes it work - in other words - what signals do you need to put in to make it go backwards and forwards.
It is unlikely that the bits of your system will be all in one. There will be a seperation some where, between the computer that did all the calculations for the system and told it what to do, and then the driver side - which took those signals and converted them into movement.
That is the point on the system you need to find.
Mach3 provides - for each axis - three wires - a "step" wire, a "direction" wire and a "return signal" wire ( the return signal wire might be common to all axis - therefore it might appear as only two wires per axis, plus a common).
On the "dir" wire, Mach 3 puts out a +5v or 0v signal dependent on the direction the axis is to go, and the "step" wire puts out a +5v pulse (or a 0v pulse - it can be altered) the frequency of which is dependent on the speed of the axis, and the number of pulses drives the axis a set distance (on mine 48,000 pulses = 1 inch or movement)
This is the basic system Mach uses - so unless you can find a place where you can input step and direction pulses, you are a bit stuck.
-
Looking again at the diagrams - are there any controls on this - in other words, how can you control it now ??
I can see a slot for a parrallel port - what is that for.
-
Ok, I understand what needs to happen here to make the system work. As Jim said, I need to find how it is all going to connect together. Jim, yes there is a controller, they call it a pendant, it is a DOS based computer system that connects to the panel shown above, it works, just doesn't do what I need it to do and will not accept large quantities of G-code. I have considered drip feeding it as well but I think it would be better to just upgrade as much as I can, please correct me if anyone has another suggestions.
I emailed the company that made it back again and asked if the servo drives would accept step and direction inputs, here is his reply
"The motors on the MX3 unit are DC motors not stepper motors. They use a variable square wave signal from the computer to move and to control direction of movement. If the signal is longer in the positive direction than the negative, the motor will move forward
in the positive direction, etc.
Tip: The "brain" for the MX3 is equivalent to a desktop computer, but it contains a special plug-in board that controls movement of the motors."
The special plug in board sounds like a controller board to me? This would be taken place by my PC, Mach and the smooth stepper wouldn't it?
Does the "variable square wave signal" sound like step and directional inputs?
Thanks again all of you for your help,
Scott
-
I think that a variable square wave is a far cry from step and direction.
Sort of like a PWM signal. Where equal high/low is no movement, 50 to 100% High is FWD and 50 to 100% Low is REV.
Just a guess,
RC
-
The guy obviously doesnt know that servo drives can also be controlled with Step/Dir signals, Also he says the motors take the square wave, thats crap, the motors will take a DC voltage and the polarity will be reversed for direction change. The drives however will take the square wave so at least you are getting some decent info. LOL
Anyway it sounds more like CW/CCW signals rather than Step/Dir but even then it desnt sound quite right. Do you have a scope? if so try and find out the pins on the drives that accept the signals from the computer and look at them to see what is happening when jogging back and forward.
Hood
-
OK, did some testing, unfortunately I don't have a scope. In the motor/driver housing I have a bundle of 4 wires, 2 wires from the motor going into the driver, also I have a constant power line and a neutral going to the driver from the control panel. The power going into the driver seems to be 120 VAC, the 2 wires going to the motor from the driver are 60VDC or 40VDC, depending on the direction its moving, they swap voltage depending on the direction.
I have several wires in a seperate bundle coming from the control panel to the driver, 1 is a constant 5 volt, 1 is a constant grond, two of the wires are either 3.15 VDC or 1.75 VDC depending on which direction I enter in the controller. The other wires don't seem to be affected by movement, basically no voltage, maybe these are from the encoder?
The driver seems to act like a relay or I should say a few relays, with some sort of voltage converter for the motor, does this sound correct?
I think, if I'm correct that most systems are powered with 5VDC, if that's the case, and with the voltage that I listed above, can this be wired easily?
Scott
-
OK first thing I would say is your drive is definitely taking digital signals rather than analogue, this ties in with what the guy said regarding the pulses. Your DC to the motor should change as speed increases, ie get higher for faster and lower for slower. Also the polarity should reverse as rotation reverses.
The wires that you are not seeing a voltage on may be the pulse wires, try setting your meter to mV range and see if you get anything, if you do does it increase with speed?
Really a scope is needed to see exactly what signals are coming from the computer to the drive, dont suppose you know anyone at a college or school that could borrow one? preferably a dual trace.
If your drives are CW/CCW pulse input then it may be possible for you to use them. Also have a look on the drive where all of the wires go in and see if there are any markings, also on any of the terminals that dont have wires connected, if there are such terminals.
Hood
-
Need to jump in here.
Your drives/amps are located in the motor housings. Input to the drives is definitely pwm and not step/direction. feedback is through the separate encoder signals.
You'll need a driver that interfaces with Mach and generates PWM output to the servo drives. I am not sure who makes one, but I will look and report back here.
You can NOT use step and direction to run these drives.
Sorry for the bad news, But I'll keep looking for a solution.
Kenny
-
I'm back!
Check here, they may be able to help. http://pico-systems.com/pwmbox.html
Kenny
-
Great info Kenny, are you familiar with these kind of drives?
Hood
-
Kenny, are you farmiliar with the prototrak system? So is what you are saying that I will be keeping the servo drives and servos that I have and adding a controller and driver between Mach and the servo drives? Sounds like I'm in need of a translator :D What is pwm by the way? Would I need the entire control box with controller, drivers and power supply, or just the drivers? If I got the entire box, would I then be connecting the output of the "smoothstepper" directly to this unit? That would be simple.
Hood, didn't you say in an earlier post that you are using picos? If so, can you tell me a little more about your set up?
Scott
-
Scott,
Yes, I am familiar with the Prototrak system. You'll need a controller like the Pico to hook to Your existing drives. I need to confirm the connections with one of my customer's machines. I will try to do that tomorrow. If I am successful, I will try and give You connections to the Pico. The Pico was developed for the EMC software which is very similar to Mach3. I have been following this thread, but want to be sure before leading You off in a direction. You would be using the Pico instead of the SmoothStepper, unless of course, they implement some type of PWM output. You should probably contact them and ask about that directly. If so, please forward their response to me and I'll have a go at the connections for You.
Kenny
-
You are the man! I will email the guys at warp9 and find out about the pwm output
Scott
-
OK, I've emailed Warp9td, I've posted a thread here in the warp9 forum, and I've posted a thread on warp9's own forum, one responce with an I'm not sure answer. So I went and did some reading on PWM, it seems this is a good way to run the servos. Seems to me that the Smooth Stepper should be used in between the pc and the pico board to take advantage of the reduction of pulses as Hood mentioned. It also seems that all I need to do is get the SS and the pico board and wire them up, could it be this simple? The pico web site has a wiring diagram of it's board pinouts and a basic diagram of how to wire a system, with that and the one from Prototrak,(the company that made the servo amps and encoders), this should be pretty simple, yes?
Scott
-
Does anybody know if Mach 2 outputs PWM? I spoke with John from Pico Systems and he says his board is not compatible with Mach3. He says it designed to work with EMC2, run by Linux. I also read somewhere that Mach2 was based off of EMC, any thoughts?
Scott
-
The way it seems is you have a few choices
1. Stick with the control you have
2. Get Geckos or Tek10 drives and take a speed drop
3. Get Rutex drives
4. Get new AC Servos and drives.
5. Find someone who makes PWM to Step/Dir converter
6. Use EMC
1 Would of course be the easiest and cheapest because you are doing nothing but it would mean you are stuck with the old control.
2 would not be a good option in my opinion as the drop in speed would probably be quite annoying for you.
3 may be OK, although I have seen people write about problems wit the Rutex drives I have also seen a lot that dont. I have no experience with them so cant comment.
4. Would be the preferred option but also the most expensive and may not be worth it.
5. Doesnt look like anything is available
6. Never used it, supposedly quite good but big learning curve especially if you have not used Linux
Hood
-
Scott,
Just found this. http://www.jrkerr.com/picsrvsc.pdf It takes step and direction input (from Mach3) and generates pwm output for Your amps. I still need to see the ProtoTrak connection drawings to be sure that this is correct for Your amps, But as it takes normal step and direction inputs, You can use it from Mach3.
Kenny
-
That looks very promising for people in Scotts position :)
Hood
-
I feel like it's Christmas in April, sweet moses that's good news ;D Thanks Kenny, I will check it out
Scott
-
Scott,
After much trial and error investigation, it turns out that the correct driver boards have been residing in my garage all along. The Galil 1755 board will:
Work with Mach3,
Enable fitting and use of the dual encoder setup that You have,
Output PWM signals to Your amps.
I know this sounds stupid, but the answer was in front of me all along. I am now going to pickup a cheap computer ($30.00) and make up a cable that will allow connection of a single motor/encoder combination, and also the secondary Trak encoder. I will get it working and send it to You for testing. If You are happy, send it back to me and I will need to fabricate an interconnecting PCB to interface between the 64 pin cables that You have and the 100 pin cable from the Galil board. This will take some time, but by doing it this way, You can continue to use Your mill until everything is ready and then simply swap plugs over to implement the controller with Mach3. It seems that all signals that we will need go through P1, the 64 pin ribbon cable header on the MX connector board.
Please call me if You have any questions.
Kenny
-
Sounds great Kenny, I will email you.
Scott