I am trying to build small CNC based on GRBL. I've bought GRBL shield on ebay and wired everything. When I try to run stepper it vibrates a lot. I've set current on driver, and numbers of steps in configuration. I'am using 12V ATX power supply. You can hear it in following video: First I thought it was motor problem, but then I've connected same motor to RAMPS 1.4 board with Marlin software. It uses same drivers (A4988). When I run it in this configuration it works perfectly. I've tried swapping drivers and power supplies between boards, but same thing happens. Does anyone have any idea what could be the problem?
Problem was that I tested it at slow speeds (feed rate 100). After I enabled microstepping and increased feed rate to 1000 it works fine.
Hi. I ve'got the same problem with my xpro v2 grbl driver, and I cannot find answer anywhere. Tried different microstepping settings and steps/mm but motor is still vibrating. I need to use mine on low feedrates for engravering. When I use it on high feedrate its still vibrating when accelerating and slowing down on the end of move. Another thing I noticed, when I tell driver to move 0.1mm stepper is not moving unless I press the button for three times. Can you post your grbl settings please? Thank you
@Hybrid what are your microstep settings? What is the step pulse length setting in GRBL? that is value $0 in the parameters $1 should be 255 to prevent disabling the drivers what motor voltage are you using? how much current can the PSU supply, and how much have you set the drivers to?
I have tried 1/4, 1/8, 1/16 and 1/32 There is really no difference. Step pulse length from 3-50 no difference $1=255 This is my motor: 13446227_1032008196834577_387152238_o by Hybrid posted Jun 14, 2016 at 10:33 AM PSU is rated 19.5A on 12v rail Drivers are set on half of currend but also tried lower and higher settings.
1/8 microsteps, 26.667 st/mm feed rate : 5,100,500,2000 1/32 microsteps 106.668 St/mm feed rate 100,500,2000 Settings from OX reseller: $0=10 (step pulse, usec) $1=255 (step idle delay, msec) $2=0 (step port invert mask:00000000) $3=6 (dir port invert mask:00000110) $4=0 (step enable invert, bool) $5=0 (limit pins invert, bool) $6=0 (probe pin invert, bool) $10=3 (status report mask:00000011) $11=0.020 (junction deviation, mm) $12=0.002 (arc tolerance, mm) $13=0 (report inches, bool) $20=0 (soft limits, bool) $21=0 (hard limits, bool) $22=0 (homing cycle, bool) $23=1 (homing dir invert mask:00000001) $24=25.000 (homing feed, mm/min) $25=500.000 (homing seek, mm/min) $26=250 (homing debounce, msec) $27=1.000 (homing pull-off, mm) $100=26.667 (x, step/mm) $101=26.667 (y, step/mm) $102=200 (z, step/mm) $110=2500 (x max rate, mm/min) (Go upto 7500) $111=2500 (y max rate, mm/min) (Go upto 7500) $112=2500 (z max rate, mm/min) (Go upto 1500) $120=50.000 (x accel, mm/sec^2) $121=50.000 (y accel, mm/sec^2) $122=50.000 (z accel, mm/sec^2) $130=320.000 (x max travel, mm) $131=525.000 (y max travel, mm) $132=68.000 (z max travel, mm)
sounds like full stepping to me, like the microstepping is actually off. if you set to 1 step/mm then command a 200mm move, how far does it move? G0 X200 if it is in full step mode, it will turn around just once. >-:
Hi. on full step mode it moves around just once but still jumping. On 1/8 setting it moves about 20-30 degrees so looks like microstepping works . both tried with 1step/mm. Just seen video abiut microstepping and it should make much smaller steps per pulse
that is exactly it, it looks/sounds like full steps. could there be a problem with the jumper connections on the drivers? maybe they are inverted or just not connected correctly? I have Big Easy Drivers that default to 16x microsteps, but the 8825's default to single step unless you fit jumpers on the CNC Shield. Caught me out at first (-:
Well, changing jumpers possition makes a change only on the travel length but not enabling microstepping. That sounds like there is something wrong with the controller. This is the one I'm using: CNC xPRO Controller V2 There is no way to mix up the jumpers. Will contact seller tomorrow for replacement. Thank you very much for your time David
I'm having the same type of issue with mine running the same cnc xpro2 control board... Z axis works great but x and y r still choppy and growly. I tried playing with many settings including microsteppjng and pulse length as well as motor current nothing seems to change it noticeably. I'm sure the psu is adequate 24v 350w running 3 Nema 23s and one Nema 17 for z. @Hybrid wat did spark concepts say?
I have the same board and looks like a similar problem. Did you ever get a response from Mike at Spark Concepts? What was the solution?
