Hello Guest it is November 15, 2019, 12:35:19 PM

Author Topic: very slow Feed issues with setup , calculated steps per not working in mach3  (Read 1342 times)

0 Members and 1 Guest are viewing this topic.

Hello guys , happy to find this community ! i been hitting the forums alot thru google search and i couldnt find a way to fix my problems in Mach3 so i decided to register , will probably be easier to show my problem instead of trying to find someone else's wich match my setup..

I retrofitted a small bench mill to 3-axis CNC


So here we go i assembled a 3 axis kit with  Nema 34 1235oz steppers with Stepper Motor Driver:DQ860MA and 350W 5.8A Single Output Switching Power Supplies

here is the ebay listing from where i bought the kit , the parts are more detailed there
https://www.ebay.ca/itm/US-FREE-Wantai-3Axis-Nema34-Stepper-Motor-1232oz-in-Driver-7-8A-fast-shipping/221683269197?ssPageName=STRK%3AMEBIDX%3AIT&_trksid=p2057872.m2749.l2649

so after loosing a whole day trying to figure out why my steppers wouldnt move i found a thread with someone saying he had similar problem and he pointed out a flaw in the wiring diagram provided. i went on LongsMotor webpage and found a 99% similar wiring but it had the ENBL+ pin connected to +5V , the connection wasnt there on the sellers wiring diagram so i made it work.


Then i went on The steppercalc excel sheet i found and with the leadscrew infos , axis and motor teethcount , with the drivers set to 1600pulse/rev it was showing me 640 steps/mm

well it wouldnt move much so i brought up the steps per mm until i got movement then went to Mach3 axis calibration and gave him a movement of X distance ,measures the travel and it corrected it to about 20 000steps per mm wich is waaaayyy out of the 640 range calculated but it now moves 10mm on the table and 10mm on the DRO , i also loaded G-Code i made thru Fusion 360 and cut a part

here it is supposed to be at a feed of 1500 something mm/min

 https://youtu.be/4WImMKD4wv4

here we see the code being worked , FRO overridden , showing 1524mm


i am unsure where to find the edit button and the forum wont let me reply saying i already posted this reply or tried to refresh , the post is incomplete


hello apparently i can'T find the edit button so sorry for the duplicate im reposting it  , will eventually find how to edit !

Hello guys , happy to find this community ! i been hitting the forums alot thru google search and i couldnt find a way to fix my problems in Mach3 so i decided to register , will probably be easier to show my problem instead of trying to find someone else's wich match my setup..

I retrofitted a small bench mill to 3-axis CNC and it is giving me a few problems


So here we go i assembled a 3 axis kit with  Nema 34 1235oz steppers with Stepper Motor Driver:DQ860MA and 350W 5.8A Single Output Switching Power Supplies

i am also using a Ethernet Smoothstepper ESS

here is the ebay listing from where i bought the kit , the parts are more detailed there
https://www.ebay.ca/itm/US-FREE-Wantai-3Axis-Nema34-Stepper-Motor-1232oz-in-Driver-7-8A-fast-shipping/221683269197?ssPageName=STRK%3AMEBIDX%3AIT&_trksid=p2057872.m2749.l2649

so after loosing a whole day trying to figure out why my steppers wouldnt move i found a thread with someone saying he had similar problem and he pointed out a flaw in the wiring diagram provided. i went on LongsMotor webpage and found a 99% similar wiring but it had the ENBL+ pin connected to +5V , the connection wasnt there on the sellers wiring diagram so i made it work.


Then i went on The steppercalc excel sheet i found and with the leadscrew infos 5mm/turn 1 thread , axis 40 teeth and motor 20 teeth , with the drivers set to 1600pulse/rev it was showing me 640 steps/mm



well it wouldnt move much so i brought up the steps per mm until i got movement then went to Mach3 axis calibration and gave him a movement of X distance ,measures the travel and it corrected it to about 20 000steps per mm wich is waaaayyy out of the 640 range calculated but it now moves 10mm on the table and 10mm on the DRO , i also loaded G-Code i made thru Fusion 360 and cut a part

i couldnt find a velocity value to get movement on the stepper when i try to go lower in the microstepping like 800 or 400 , it would do a single thud barely audible on the stepper but i can feel it with my hand , when on 1600 pulse/rev on the driver i can make it move but doesnt moves the right distance if i am not at 19960 steps per mm

also i am not sure about something for the power setup dips on the drivers . the motors calls for 5.6A current rate and i set the drivers to the closest value wich is 5.7A peak (4A RMS) i am not sure to wich value to set it at so i went for the nearest peak amps. are the steppers asking for RMS or PEAK amps ?????

here it is supposed to be at a feed of 1500 something mm/min

 https://youtu.be/4WImMKD4wv4

here we see the code being worked , FRO overridden , showing 1524mm/min programmed feed but showing 118 units/min and  0 units/rev

https://youtu.be/5lIn5bZtigc

here i am showing the motor tuning section , the values and the actual movement of the table
i am getting the correct distance traveled at 19960steps per and i can't go over 156mm/min or the stepper stalls , tried very low to medium high accel , when on low accel i can hear the steppers ramp up slowly and then stalls

https://youtu.be/Y4KT_YoHnUU


here i include the XML file for the MACH3 settings if somebody can find where is the problem i would be eternally thankfull !!!
could anyone delete my thread  please ? i found a pretty dumb error on the drivers .... since when do you pull a switch down to turn it on? never saw the ON markings on the header my drivers are in a box.... all inverted ... now  feeds accurately and i had to stop the stepper tuning velocity tests at 4000 mm/min because it was getting too dangerously fast for the lenght of my axises... please kill me... 

Offline Tweakie.CNC

*
  • *
  •  7,997 7,997
  • Super Kitty
    • View Profile
    • Tweakie.CNC
Hi Letomoto,

I am pleased that you found the problem.
If it’s any consolation, you did not make a dumb error. Switches are always pulled down for ON here in the UK so you just made an easy mistake.  :)

Tweakie.
Success consists of going from failure to failure without loss of enthusiasm.  Winston Churchill.
Well it does work like a charm now and i broke my first endmill hahaha , was a cheap chinese hss 1/4" tool , was experimenting with the feeds . cant go higher than 2000rpm on the spindle of the mill/drill so i gotta watch the feeds pretty closely with small tools
I was running at 500mm/min in the gcode but i quickly realised the cutter wouldnt hold at 2000rpm (max spindle speed of the mill/drill , i will probably end up putting a faster motor with a code driven VFD ) so i brought the FRO down to 160mm/min. It now reacts when i play the FRO.... Darn switches!!!! Then i put it to 200mm/min because it was slow and it broke 30 seconds later. Getting more cutters today to finish this part .

This is the first aluminum project im stepping on i am very excited! Did a bunch of small stuff with the manual mill but i always ended up digging on a contour by moving the wrong direction on the handle and getting uneven toolmarks. Ive been dreaming about a CNC for the past 10 years and i finally built my own im very happy , learned a lot of stuff and new doors are opening quickly!!

Offline Tweakie.CNC

*
  • *
  •  7,997 7,997
  • Super Kitty
    • View Profile
    • Tweakie.CNC
You must be gifted - the cheap endmills hardly ever break, it is usually always the expensive ones that go.  ;D

Tweakie.
Success consists of going from failure to failure without loss of enthusiasm.  Winston Churchill.
Haha well im happy the cheap chinese one broke but it was the only 1/4 i had so i couldnt finish my program :-(

With wider cutting tools i am gonna be able to work with my spindle max rpm better . a half inch endmill asks for half the speed of the 1/4 for the same feed and is also stronger . probably a better 1/4 cutter wouldnt break at the same feed.

Got some more cutters in the shop but the holes it has to drill are too small for a wider cutter so project stalled , gonna get equipped with better stuff real quick now that im gonna start using the mill alot! Its gonna be expensive... I want collets, chamfer/deburr tool , a few units of a few sizes/shapes. The air nozzle/mist cooling kit is on the way. Will probably end up setting a 4th axis on the table , its probably gonna get even more interesting!

Offline Davek0974

*
  •  2,580 2,580
    • View Profile
    • DD Metal Products Ltd
Sounds like the fun is just starting :)

FYI, just incase you have not seen it, maybe have a look at HSMAdvisor for a speed/feed calculator - i find it really helps when machine factors like spindle RPM or power are limited, I cant go over 3000rpm on my Bridgeport (yet) and it calculates better feed rates etc to compensate.
Bridgeport Mill, Mach3 V062, CSMIO-IP/A controller, AC Servo Drives
oh thats pretty cool :-) thanks! was actually wondering how i would scale down feed from speed thats gonna get usefull!


according to what i entered , 1/4' 2 flute HSS at 2000rpm it shows about 250mm/min but China toy cutter was obviously not up to standards

next cutters ill be able to get more info on them from the manufacturer and enter the specs in the software yay !