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Mach3 4th axis assistance Is Mach4 better for this?
« on: August 28, 2017, 10:20:10 AM »
Recently bought a 4th axis on ebay.  when running the 4th axis with X axis successfully made one pass then problems arose.  the Command F250 X4.5 A270.  Completed and stalled after one pass. Mach3 version .062. It appears my c-10 BOB decided that was the end from AutomationTechnologies.  Started with X axis stopping, then Y Axis finally the entire board.  Also using KL-5056D and KL-8070D.  Finally resolved with new BOB - C11G from another supplier.  And new Gecko 213V stepper drivers.  Not sure if the Keling Drivers are bad, think thye might be.  Also Y axis motor not as smooth as it used to be.  Even after adjusting trim posts , replacing that motor.

48V Keling supply Nema 23 570s and a Nema 34 906 rotory 3.5 Amp nema 23 57.

Work fine in testing yesterday with upgrades.  ran a short test run with simultaneous x and A axis moves.  Not sure what the A Axis settings should be at 10 MS .  Always ran 10 MS at 10160 at 20 (don't need much more will eventually settle at 40 fps) on velocity for x y and z.   Have Steps per degree at 33.333334
6 gear reduction  takes a very high velocity like 8000 and acceleration turn up to operate.  Is this about right?  Not comfortable having to set so high.

Thought it could be the stepper motor the Nema 23 57 which is a designation I don't understand.

Amperage's set up right on Stepper Drivers.

Windows 10 through an ESS SmoothStepper.  Everything is optically isolated now.  I did try the companion board for the smooth stepper and it did't work, but I think it could be the KL stepper drivers.

Will Mach4 Hobby drive the 4th axis better without the excessive Feed Rate?  Setting the Feed Rate at 200 to 250 seems like a bad approach and I wonder if that was part of the troubles.

Any assistance would be useful.  I bought a new controller box ( computer tower ) with more fans and real estate have been using the ultra tight fitting Automation Technologies box which I was never satisfied.  Heat sinks and all should be much better.

I will take a picture after I am done.  The testing went fine so it is put it together permanently.  Driving a G-0704 mill.  Still looking for a belt drive conversion for the mill.

Thanks for any assistance you can offer.
Re: Mach3 4th axis assistance Is Mach4 better for this?
« Reply #1 on: August 28, 2017, 03:12:18 PM »
Hi,
not quite sure what you are asking, sounds like several issues, sorting one by one is likely to result in less confusion.

If you are using the same motion controller (ESS) then it doesn't make any difference at all between Mach3 or Mach4. Mach4 is no faster,
more accurate or anything else, its advantage is the modular modern programming style which results in fewer bugs and WAY better
customisation ability. Likewise you can have fans up the yahzoo, a CPU with muscles on its muscles and it won't make your machine
run any faster. Your problem is not computing but your stepper/driver combination.

Suggest you start by checking each axis one by one. Put ridiculously slow speeds and accels and build up until you find the point where you
start losing steps or stall, then back off, significantly if your being conservative.

I can't work out what your A axis gearing is from your description but sound like the stepper has to spin WAY too fast to achieve the resultant
speed you want. Either change the gearing or fit a servo. A stepper loses authority beyond about 500 rpm down to about a 1/4 of its grunt at 1000rpm.
I find it hard to believe you can spin a stepper at 8000 rpm, aside from anything else the rotor must be due to explode with centripedal accel!

Craig
My wife left with my best friend...
     and I miss him!

Offline ger21

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Re: Mach3 4th axis assistance Is Mach4 better for this?
« Reply #2 on: August 28, 2017, 03:19:28 PM »
8000 is degrees/min, which is about 22rpm.
Gerry

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http://www.thecncwoodworker.com/2010.html

JointCAM Dovetail and Box Joint software
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Re: Mach3 4th axis assistance Is Mach4 better for this?
« Reply #3 on: August 28, 2017, 03:58:53 PM »
My 4th axis is 6:1 ratio.  running G0 runs normally.  Running G1 at 10.0 feed rate the rotation is very slow as in moving but barely perceptible.  a combination command at about 200 Feed rate will make the combination of axes run maybe around 5 feed rate which will cut a spiral on 3/4" aluminum rod.   if the 4th axis is not involved then runs normally.  Posts on this on similar threads sugggest to raise the Feed rate until it moves normally. That worked until I had a failure.  I hate to use less steps.  The vague instructions say to run 1 degree required pulse.

I think the high feed rate (250) that I have to run may have ruined my previous equipment that ran fine for 6-7 months.  I am pretty sure that the BOB was marginal to start with, but the stepper drivers without a oscilloscope or willingness to use my new BOB that works seem suspect as well.  The proof of the pudding would be to wire the stepper drivers to the new BOB and try them out.  The only new feature is the 4th axis.

My question is two fold, is there a better solution than increasing the feed rate?  And will Mach4 which is supposed to have better 3D graphics work any better with the 4th axis?  I really hate to artificially raise the feed rate to get better  movement I am not looking for a terribly fast feed rate but will need to cut around 3.0 in steel.  so 3/4" twisted flutes on steel at 45 degrees for a total of eight flutes, rotating 270 degree over 4 to 4.5 inches.

My question was on speed do I need to raise the speed to those really high numbers in the motor setup for the a axis rotation just to make the motor turn at a normal rate of speed? 

Not asking a lot the programming is easy and I am using the diameter (radius) after the cut for Mach3 to calculate the correct moves.  in other words

G1 F3.0 Z0.372
G1 F250.0 X4.5 A270.0

That is as simple as it gets.  I need a high feed rate to get reasonable movement on both axes.  Otherwise a simple x,y,z movement would be and is F3.0 to 5.0.

Re: Mach3 4th axis assistance Is Mach4 better for this?
« Reply #4 on: August 28, 2017, 04:01:54 PM »
By the way that is a .003 cut on the z axis for 3/4" bar stock using the radius to calculated the cut.  Just in case you are wondering.

Offline ger21

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Re: Mach3 4th axis assistance Is Mach4 better for this?
« Reply #5 on: August 28, 2017, 04:03:31 PM »
There's an option in Config Toolpath for 4th axis feedrate. Then, on the settings page, you need to enter the radius of your part. Then you should see proper feedrates.
Gerry

2010 Screenset
http://www.thecncwoodworker.com/2010.html

JointCAM Dovetail and Box Joint software
http://www.g-forcecnc.com/jointcam.html
Re: Mach3 4th axis assistance Is Mach4 better for this?
« Reply #6 on: August 28, 2017, 06:56:12 PM »
Hi,
phew! 8000 deg/min-much better. At 10 microstep I come to 33.33334 steps per dregree at 6:1 like you.

Tkanks ger21 for clearing that up!

Craig
My wife left with my best friend...
     and I miss him!

Offline rcaffin

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Re: Mach3 4th axis assistance Is Mach4 better for this?
« Reply #7 on: September 11, 2017, 05:43:31 AM »
Yeah, A axis can be tricky wityout a radius set.
F10 g1 A100 (from A0) will take 10 minutes! That's 100 degrees / 10 degrees per minute.
Cheers
Roger
Re: Mach3 4th axis assistance Is Mach4 better for this?
« Reply #8 on: September 11, 2017, 01:14:55 PM »
Hello

If you notice the programming the radius information is given by Z axis position.  There seems to be two schools of thought:  1 is put the radius information in the Mach 3 screen as you and ger21 suggest and the other, which seems to me Hoss has said is raise the feed rate to 200-300 or more and suddenly you get much better feed rates.  I tried the latter and crashed my controller.  I don't whether the BOB which was probably suspect, I felt that for some time a C-10, or it was too much for the system.  I have a new C-11 board and gecko drivers and testing runs fine.  Will be finishing the new controller box today and should be up and running.  I can try both methods.  Next step is to buy a power cleaner of sufficient size, I believe the power sine wave has a lot of garbage in the sine wave, already use one a gem scale which eliminated the voltage fluctuations which played havoc on its accuracy.

I built a new controller box out of a tower so there is room for expansion and reduction of heat through 3 fans.  I  have heat-sinked the Gecko Drives and now every component is opti-isolated.  Separated the power supplies from the rest of the equipment and added a power switch for the 4th axis so the driver will not be powered unless it is in use.  I have isolated the ESS smooth stepper power with an external charger.

Still don't know if the KL-5056 and 8070 D steppers are harmed or not, if I can determine how to test them I may use on another project either running an old craftsman lathe 6 x 18 or a 4 axis router with much smaller stepper motors.  I am very sure that the cheap C-10 board is not functioning.  I have one rough running 570 oz NEMA 23 motor, which I replaced always keep a spare,, the cheap Chinese stepper motors do not seem to have great life spans.  I will buy better stepper motors in the future.  I have lost two of them in 8 months.  It may be either the stepper drivers or that C-10 as well. I have kept the drivers just under 5 amps for the 570 oz motors.

I have pretty heavy usage for a hobby machine, already wish I had a bigger mill (Taiwanese built) than the G-0704.  I have a lathe which has tremendous tolerances, which will never be a CNC. 
Re: Mach3 4th axis assistance Is Mach4 better for this?
« Reply #9 on: September 11, 2017, 01:21:52 PM »
There's an option in Config Toolpath for 4th axis feedrate. Then, on the settings page, you need to enter the radius of your part. Then you should see proper feedrates.

See my post today which explains partially that I tried this first and got very unacceptably slow performance.  As others have posted in this topic it would take the better part of a day to do any machining as slow as it moves.  When I tried putting the radius information on the Z axis and made the feed rate 250 it worked normally, but only worked on one pass.  In order to reduce operations in the way you describe, I would have to make a single .135 inch cut per flute just to be done in a reasonable time.