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Topic: Abnormal vibration of the motors (Read 560 times) previous topic - next topic

rao2_it

Hi all, I built a cnc piloted by Arduino R1, cnc Shield with Driver 8825 and GBRL. The engines used are nema17, and the shield is powered by 24volt. My problem is that when I make the cnc work or I move the motors, they move normally but emitting a strange noise over exaggerated vibrations. For me it is the first time I use arduino for piloting, other times I used in other my electronic cnc kits ready and these noises have never warned them. I calibrated the war on the drivers, following some guides found on the network, the voltage to be calibrated was 0.72 volts, but even in this case I have abnormal vibrations, I took it to 0.5 volts and the problem recurs ... Finally I took it to 0.25volt and things seem to be better but I lost a few steps. Someone could help me find a solution. Thank you

MarkT

What microstepping settings are you using? - are they different from the "other cnc kits" you have?  Heavy vibration is a symptom of using full steps or very coarse microstepping.

Is the mechanical setup using leadscrews?  That is worse for vibrations/resonances than belt drive.
[ I will NOT respond to personal messages, I WILL delete them, use the forum please ]

rao2_it

The microstepping settings I use is Full steps. I can not compare them with other cnc machines made and electronic because they are completely different.
The mechanism is composed of a belt drive on one axis and the other two with an 8mm screw.
I will try to change the number of microstepping and let you know how it went. Thanks so much

rao2_it

$0=20 (step pulse, usec)
$1=25 (step idle delay, msec)
$2=0 (step port invert mask:00000000)
$3=0 (dir port invert mask:00000000)
$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=0.010 (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=0 (homing dir invert mask:00000000)
$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=5.000 (x, step/mm)
$101=25.000 (y, step/mm)
$102=250.000 (z, step/mm)
$110=500.000 (x max rate, mm/min)
$111=500.000 (y max rate, mm/min)
$112=500.000 (z max rate, mm/min)
$120=1000.000 (x accel, mm/sec^2)
$121=1000.000 (y accel, mm/sec^2)
$122=10.000 (z accel, mm/sec^2)
$130=200.000 (x max travel, mm)
$131=200.000 (y max travel, mm)
$132=200.000 (z max travel, mm)

Thi is my configuration on gbrl
 Help Me

MarkT

The steps/mm settings just need to match the actual number of (micro)steps that will produce 1mm linear motion for that axis.   $100/$101/$102 are the floating point values that set this.  max velocities and accelerations have to be determined by trial and error in practice, start low, increase till it just misbehaves, then
back off 20% or so.
[ I will NOT respond to personal messages, I WILL delete them, use the forum please ]

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