Topics

11

General Mach Discussion / Mach 3 and a Stepper Spindle

« on: January 03, 2016, 10:03:55 AM »

I have Mach 3 running my homebuilt mill and I have added a HF lathe bed, headstock and tailstock ala Tormach . The headstock is driven by a large stepper motor with timing belt reduction and works fine as a 4th axis.  It reliably positions and runs the spindle at 600 rpm. However I'd like to be able to run it as a lathe with the stepper running continuously, as I have a Tormach QC Tool Post mounted behind the mill spindle.  However my set up is a Xulifeng USB motion card with 4 axis and supports only a pwm spindle.  Mach 3 supports a stepper or servo spindle using step and direction, however I can't see a way to make the outputs from Mach 3 use the 4th axis outputs of the Xuifeng card as the spindle.  Anyone know how I might do this?  Alternately I am thinking to add a pulse generator to generate spindle speeds and put an encoder on the spindle for threading.

At this point I am so close, and so far!

12

General Mach Discussion / 3D printing with Mach 3

« on: April 06, 2014, 09:48:36 PM »

Okay,
I think I am in trouble here.  I installed a 4th axis stepper motor to drive the extruder.  However in looking at how 3D printers work with the G-code output from a slicer, the extruder is run at fixed speed like a spindle. I got the extruder to work as the C axis and can manually jog it just fine.  I can also enter a feed and distance and it runs fine.  So I thought, okay I need to set up the spindle to be a step and direction type output.  However here is the gotcha.  I have a Xulifeng USB motion card with a Mach 3 plugin doing the motion control. I don't see any way to get step and direction spindle operation with this card.

If Mach 3 could use the A axis as a spindle it would work.  If the motion card could use the 4th axis as the spindle it would work. I don't see any setting to make this happen. Anyne know if this is possible?  This also suggests I am screwed when it comes to using my stepper driven lathe as a lathe. It looks like it can be used for positioning, but not for continuous motion.

I have a smooth stepper card and breakout board, but didn't want to go to the effort of installing them at this time. So the question is can the smoothstepper card use a stepper motor as a spindle drive?  I thought I was ready to try 3D printing, and now I am really stuck.

13

General Mach Discussion / 3D printing with Mach 3, who is doing it?

« on: March 16, 2014, 09:31:14 PM »

I have just about got the extruder installed and wired, and the heated bed is working, almost.  The bed controller melted down due to a cheap under rated connector, and the extruder stepper motor is bad, another motor runs just fine on the drive.  I realized the QuBd extruder I bought was a really poor design and had to redesign it before I even mounted it. So I am ready to finish up configuring it, and I have questions about what others have Mach 3 controlling and how that works out.  Anybody got a Mach 3 printer running?

Thanks,

14

General Mach Discussion / Limit rapid speed from a digital input

« on: February 17, 2014, 08:37:12 PM »

I have door switches that stop the spindle if you open the doors on the mill, to protect my grandson.  I'd really like to be able to limit the rapids to a slow speed when the doors are open too.  The machine could easily crush a hand with a quick move, but you need to reach in sometimes to locate a part. When the doors are closed the rapids should be whatever they are set for.  Is this possible?

Thanks,

15

General Mach Discussion / Using Mach 3 for a Rostock Delta printer

« on: February 15, 2014, 03:54:07 PM »

I'm building a Rostock Delta style printer.  I'd really like to use Mach 3 to drive it. However it is not a cartesian XYZ axis arrangement.  Instead there are 3 vertical linear axis arranged in a triangle. Z moves involve moving all three axis at the same time, as do X and Y moves.  So the computer must calculate the kinematics and move the axis appropriately.  So the question here is could this be accomplished by Mach 3?  Could a plugin be written to handle the kinematics?  I am not a programmer, I'm the mechanical guy. However my buddy who is actually getting the printer is something of a computer whiz and could probably pull this off if it was possible.

Thanks.

16

General Mach Discussion / How fast?

« on: January 11, 2014, 11:31:06 PM »

I've had my CNC mill running for about 6 months and tuned the motors for 100 ipm rapids.  It has 18 inches of travel on all three axis. However I got wondering about how quick it might actually be able to run.  So today I played a little with motor tuning.  My axis are all driven by 20 mm x 5 mm pitch ball screws and the ways are THK recirculating ball type.  I have a Xilufeng USB breakout board driving Leadshine 80 volt steppers with a 68vdc power supply.  The motors are Nema 34 860in/oz holding torque.  Z axis mass is about 50 lbs, Y axis is 40 lbs and X axis is 85 lbs with a stationary 205 lb table.

I was able to tune it to work well with all axis running at 320 steps/mm, 8700mm/min and acceleration set at 2200.  That's a stepper motor speed of 1740 rpm, and 342 in/min rapids.  Its a little scary watching it move at those speeds!  Is this a good rate or are some you running much faster?  I tuned it back down because I have my grandson working with me and I don't see actually cutting at those speeds.

17

General Mach Discussion / Not getting how to use tool length offsets

« on: July 23, 2013, 09:14:59 PM »

I've used tool length offsets extensively in the past on a Fadal and also an old Bandit controller.  However I am just not getting it with Mach 3!  I crashed a drill into a part destroying it after I thought I understood from a test run. What I wanted to do was use my edge finder as a touch off tool to find edges and the top of a part.  So I was going to call that tool zero and always leave it setup.  I have tool height setter with an LED and 0.200 overtravel that is 2" tall. So I was going to pick a spot on the table and always place it there. Once all the tools are set on the presetter I should be able to pick up the sides and top of the part in the fixture using tool zero and set all axes to zero. Then tool changes that call tools 1 and up should get positioned correctly.

Issues that I see:

I see where there is a tool change position X=0 Y=0 Z=5", but a tool change called in g-code from Cambam does not move to a tool change position.  The move appears to be enabled on the settings page. What else controls this?  What code makes it do the move? Does the tool length offset get applied first after the tool change, moving the Z so the tip of the new tool is at 5"? I think if the machine doesn't move to the tool change  position then everything else pretty much fails.

Thanks,

Gary H. Lucas

18

General Mach Discussion / Need to sell something

« on: July 12, 2013, 06:15:32 PM »

I have an electrical part that I got by accident and want to get rid of. It might be of interest to someone building a CNC.  Haven't sold it on Ebay yet, hate to just toss it. Where can I advertise it?

19

General Mach Discussion / The discouraging state of DIY CNC

« on: June 21, 2013, 08:50:49 PM »

I just got a ESS Smooth Stepper board and a CNC4PC breakout board to go with it.  The stepper board is nicely made, with large mounting holes that the average home CNC builder should have no problem mounting it.  However the CNC4PC breakout board is a serious disappointment!  NO mounting holes at all!  Connectors for wires all the way around and not a mounting hole anywhere!  Do machines vibrate?  Wiring diagrams?  In their PDF manual page 3-2 was missing completely.  No big deal, that's just the only page that deals with ALL the outputs!

I bought a little stepper pulser card to control a stepper driver for motor testing.  No instructions. A couple of jumpers that aren't marked. Terminals marked +12, Grd, Puls, and Dir. Should be simple to hook up right?  Motor runs smoothly in one direction, chatters like hell in the other.  After screwing around for 1/2 an hour I discover that this card actually implements forward pulses and reverse pulses, NOT pulse and direction as marked!

I bought a heater control board of 3D printing.  No instructions.  Two boards stacked in an offset.  One tiny set of mounting holes through both boards, and they don't line up!  NO marking of the pins except for power plus and minus. Came with a booster card with input and output terminals, not even marked for + and -.

It is unbelievable what people are apparently willing to accept.  I have a friend who just bought a million bucks worth of surface mount assembly machines, and he is the best microprocessor guy I know. He used to build a single board computer for me that went in machines that saw 120 degrees continuously and the failure rate on the hundreds of boards I bought was really low.  In fact hundreds of them are still running 18 years later I'm going to have to ask him what it would cost build some quality stuff here in the US.

Gary H. Lucas

20

General Mach Discussion / Modal Subroutines

« on: June 17, 2013, 10:10:18 PM »

On the fadals I programmed they had a Modal Subroutine.  You write a subroutine, make it modal, then it functions like a canned cycle.  After each move the subroutine executes until you cancel it with a G80.  It was great for making a number of odd shaped pockets, creating a mill/bore type routine, holes with O-ring grooves etc.  Is there any way to do this in Mach3?

Gary H. Lucas