Thanks for taking the time out to do a great tutorial that put the motor tuning in layman's terms lots of good info . now i have alot better understanding how it works . even though my system is a cnc plasma cutter but in mach3 should be the same
Great video, I am in the middle of setting up mach3 my 4.5A motors are running too slow, I'll try this method see if it makes any diffence. Thanks again, you got my thumbs up for this one
I built a Little Machine Shop mini mill with a CNC Fusion ball screw setup . I make parts on it but cutting circles has always been a joke . I end up with flats on each side or an oval circle out about .012 . I took the backlash out of the Y and Z by making solid aluminum couplers . I have checked the X and Z with an indicator and get good readings . Always returns to zero . Im thinking its a tuning issue . I need to go through the driver tester again cause I was doing it wrong . I tried 45hz and 25hz is where I was running it . Im using a Pentium 4 with the parallel output and a Gecko driver with Nema 23 at 48 volts . I havent replaced the coupler on the x yet because backlash was always set at .002 on this one . Y and Z I have set at 0 on backlash and they repeat great . I also want to mention that something I did playing with the tuning moved the flats from 12oclock and 6oclock to like 10 and 4 . I never really did tuning before now but I want a circle at the most only .001 out of round . Any ideas ? Thanks for the cool vids
I just re-read this comment after 9 months and realized now what you meant. Yes, you can control the current going to the stepper motors it's usually a pot found on the stepper motor controller circuit board, that you can turn with a screwdriver and use a voltage reference meter to calibrate. This should only need to be done one time though, unless the power supply or the stepper motor are changed. Hope this helps someone. Apologize for the mix-up.
Personally I suggest setting the steps per based by the threads per inch on your rods, the amount of microsteping and stepper steps per rev FIRST. Then use the calibration in the setup screen. Doing that first will get you within a few percent of dead nuts accuracy. The friction in the ball screw and bearings will result in the actual travel being a tad less than the calculated distance.. Thats why you need to ron the thingy in the setup screen. It Corrects for frictional losses. Its also a good idea to check the calibration now and then as the frictional looses will vary over time. Measure the length all the way from home to max travel using the steps per in the setup screen. If you cant accurately measure that far then use the max you can centered somewhere in the travel. The greater range you can use the better the overall accuracy will be. as an example using a dial indicator with 1 inch travel--- if you get to say 1 thou for he inch and assuming say 36 inches TOTAL travel that 1 thou off wil result in being 36 thou off for the entire travel. 36 thou is roughly 1/32 inch. You can get real close by using a yardstick where one end goes down to 1/32. Set the high number end twords your home position. Use the finest point bit you have, typically some engraving bit. Position the tip as close as you can get it to say the 35 inch mark center line. use say 35.5 as the distance to move. If youre dead on the point if the bit will wind up exactly over the half inch mark . Correct position by 1/64th or .0156 a time to really zero it in. .0156 is exactly half the distance between those 32nd ticks.. It will be easy to get down to right at a .015 off for the ENTIRE travel length. Less than that is possible depending on your eyeball calibration. a 64th off over 3 feet is way beyound what good woodworking requires... I get right at .003 short over 2 feet on both X and Y and .001 on Z over 5 inches. Measured using precision gauge blocks and a dial indicator. That setup is within half a thou... I use 460 oz/in steppers on all 3 axis with divide by 2 microsteps driving 1/2 10 acme rods. A divide by 2 micro-stepping cuts the effective torque of a steper by roughly 30%. Higher micro stepping cuts the power even more. X and Y are 5 starts and Z is the normal 1 start. A single start 10 pitch riod will give 1 inch of travel for 10 stepper revs. The 5 start requires just 2 revs to get an inch. Never have been able to stall the steppers and around 300 IPM is doable. Ive actualy snapped a 1/4 bit clean into hitting a clamp at 130 ipm and even that didnt stall a stepper but I suspect it lost a few steps. I stay with 130 max as the ramp up and down at 300 is no faster over all. Before using the built in calibration, set the stepper ramps and max speeds up FIRST. If that's not right you could well loose steps and that basically makes ANY calibration basically worthless. You can find all the info needed in both cases in the MACH 3 setup manual on the artsoft web site.
The 5 came from the default setup in mill. I wouldn't change this unless you are having problems. You can read more in the Mach3 manual about this subject .
Dear friend .. my stepper motor is heated a lot and read in several forums that have to be configured in half current .. and I do not find where to configure that option in mach3 the step motor is 3.2 A and is configured in 2.2A And the driver also heats .... thanks for your answer.
Just curious why you don't base your travel speeds off of the general rule of 50% of stall rpm, ie 1200 max rpm is standard on 1.8 degree steppers. Not a critique, just curious because you seem to have a solid foundation in electronics and wondering if you have ever done it using math.
Good instructional video :)...This acceleration setting....Is it this setting that causes some machines to slow down when they get to a corner or directional change? I see some CNC routers slowing down before they get to a corner, make the turn and accelerate again...or....is it the CAM software they use? Vectric for sure doesn't have such a function but it makes sense to me especially when you are doing fine work...
I knowo this is an old question but I'll answer for the benefit of others. Cam software can be programmed to slow down on corners or intricate parts based on whatever criteria you set. However it is also very likely that you have seen machines with low acceleration settings making the acceleration/deceleration audibly noticeable.
steve, looking forward to some positive changes for sure. as far as mach 3, I have nema 23 and sometimes I lose steps as I could hear the motor squeal. I can lower the sliders and it won't slip but is there another parameter I can change other than the slider to get more torque out of the motor so I can have faster motor action. it works ok with slower speeds but I believe this setup will work at higher speeds if tuned properly. hope this makes sense. I have a gecko drive. my 3 motors are pretty much the same size as your new one so I'm pretty sure it should handle higher speeds. thanks jerry from fontana ca.
Do the Gecko controllers have a current adjustment on them? Should have a way to turn up and down current to each motor. Lookup your motors max amp reading and adjust the current references in the Gecko as I have done. Sorry no experience adjusting Gecko but should be very similar.
John Boyd hi John yeah... I'm still alive thanks for asking. I haven't been in the mood lately to make any new videos but I feel an urge coming on soon. take care
Hi, I have an old HObbyCNC board called the FoamPro Ver1. running 130 Hobbycnc steppers. I noticed you are running a Hobbycnc board as well. I have a problem with losing steps when running the roadrunner program. the y axis(slaved to A axis) loses steps really bad. I can high speed jog the machine all day and it works pretty good but when running road runner it freaks out. It even does it without steppers mechanically connected... y axis steppers jitter really bad and never come back to my test marks(losing steps). How did you calculate your steps per(8005). I always come up with 16000 for mine? When i do the auto set step thing in settings, it automatically sets my steps per at 2001.25??? Anyway sorry for long comment! Oh I've backed my acceleration and velocity way down. Cheers, Lyle
first make sure you are in inches instead of metric. That will mess with your ipm and it sound like a suspect. After that try running the Y without 2 motors, noise is most likely the culprit. let me know
Thanks, I had that problem also at first but have it corrected now. I just discovered that i have my vref's set way too high. .380 when should be .280 on 130 oz. servos wired serial the way i have them. I have a diy power supply with 18v 10 amp transformer and a 10000 uF cap but i think the cap should be around 35000 uF. I'm getting 25 v untapped voltage and drops to 22 v under servo load? that doesn't sound right to me... voltage shouldn't drop that much should it? Anyway, i don't want to eat up your valuable time so thanks for your help! Lyle
I reset my vrefs etc. and it's still a little sketchy on losing steps on y axis which is slaved with A. My gantry is fairly heavy for the motors so i think i'm trying to get too much out of them. Z and A axis work really well and don't lose steps so im going to save this old HobbyCNC board and 130 oz motors for a small 3 axis setup possibly 3d printer. Thanks for your help! Lyle
Hey guru r u good at troubleshooting stepper motor / controller driver issues? Ive got all 3 axis running like crap rough herky kerky and slow...on my diy cnc using tb6560 Im still thinking its controller driver issue...if i run a continupus jog mode .....once in a while the motor will go from slower feed rate grinding rough movement to smooth movement faster feed rate but only for less than 1 second... Odd that all 3 sxis do the same thing though...usually mot all axis go bad at same time..however this is a low end junk all in one board so its possible...
@Reuel T thanks guru...well all i did was change from a windows7 to a windowsxp laptop and the motors run fine now....not sure if it was a windows siftware issue or laptop/port issue. ...i know it has something to do with what u mentioned pulse..because when i did a test in mach3 win7 it said poor...when i did in windows xp lsptop it said excellent...also funny u mention 36v ps...on a diff diy cnc i have..i upgrsded from 24v to 36v and kept the 24v fan...the fan runs 50% faster...i bought a stepdown voltage regulator board to correct this but havent installed it yet...
thank you for the video, im running mach 3 R3, witch seems to have a different user interface than everyone on here, or in the manuals..... anyways, everything applies, but the "steps per inch" button is not there, it is not on any of the pages presented and I've checked every menu, page, option setting, every thing else is on point, but where do you get the velocity and speed numbers ? thanks man,i really liked the video
