BP Steppers and Gecko Settings

[ranchak]

I've finally got my motors working, now I need to set them up in Mach3. I tried to use my original settings that I was using with Hillbilly's BOB, but all I get is a growling sound from the motors. I also tried some of the settings others have posted here, but again all I get is a growl. I did get the motors running smoothly, but their movement is off, an inch is not an inch. Any ideas? This is what I have the settings at:

Steps = 1000
Velocity = 800
Acceleration = 200



My old settings were:

Steps = 1000
Velocity = 100
Acceleration = 16


Any thoughts???

[HimyKabibble]

Originally Posted by ranchak I've finally got my motors working, now I need to set them up in Mach3. I tried to use my original settings that I was using with Hillbilly's BOB, but all I get is a growling sound from the motors. I also tried some of the settings others have posted here, but again all I get is a growl. I did get the motors running smoothly, but their movement is off, an inch is not an inch. Any ideas? This is what I have the settings at: Steps = 1000 Velocity = 800 Acceleration = 200 My old settings were: Steps = 1000 Velocity = 100 Acceleration = 16 Any thoughts???

Acceleration = 200 is *crazy* high! Start very low perhaps even 1, and go up from there to see what it can actually achieve.

Steps=1000 implies you have direct-drive, 200 steps/rev, and 5-pitch screws, or the equivalent. Is that what you actually have?

Regards,
Ray L.

[ranchak]

HimyKabibble, I have 1:1 ratio. My suggested settings for Hillbilly's BOB was:

Steps = 1000
Velocity = 30
Acceleration = 1

If I run these settings the machine sounds like a retarded machine gun! If I go with something like:

Velocity = 100
Acceleration = 10

I get the same results. I can run a slower acceleration and velocity, but the machine is slooooowwwww. I think if I remember correctly I was running something like:

Velocity = 100
Acceleration = 16


Anything other than this the motors would slip.

[HimyKabibble]

Originally Posted by ranchak HimyKabibble, I have 1:1 ratio. My suggested settings for Hillbilly's BOB was: Steps = 1000 Velocity = 30 Acceleration = 1 If I run these settings the machine sounds like a retarded machine gun! If I go with something like: Velocity = 100 Acceleration = 10 I get the same results. I can run a slower acceleration and velocity, but the machine is slooooowwwww. I think if I remember correctly I was running something like: Velocity = 100 Acceleration = 16 Anything other than this the motors would slip.

If you don't get smooth operation at low acceleration and velocity, then something's wrong with your setup. What power supply voltage are you using? Are you sure the motors are wired properly to the Geckos? What current limit do you have set? Are these the stock BP motors?

My understanding is the original BP steppers operated on high voltage, like 160V, which the Geckos can't handle. At such high voltage, they were probably also high inductance, which will make them slow when driven at lower voltage.

Velocity simply sets what the mac speed will be. Acceleration determines how fast it will ramp up to that speed. Set low acceleration, like 1, and see how fast it will go. If it doesn't move smoothly at an acceleration of 1, then velocity/acceleration settings are *not* your problem. Do you have the Step/Dir pins polarity set correctly? Which Geckos are you using?

Regards,
Ray L.

[ranchak]

I'm using G203Vs, I am running them at 64.3 volts, 7 amps with the stock motors. It seams like the DRO on Mach is multiplying the actual movement. I wired my motors like this:

To connect the phase windings in series and set the controller to 7
amps ( GECKO wiring recommended for orig BP type steppers*********)
terminals:
6 jumpered to 5
3 connected to phase A+
1 connected to phase A-

8 jumpered to 7
4 connected to phase B+
2 connected to phase B-

I'm using an Antek power supply and rectifiers, 12 volts to my BOB (PMDX-122), spindle controller (which I haven't got to work) and relay boards. What a long weekend!

[123CNC]

You mentioned an inch indicated does not come out an inch travelled? You might want to check that you have selected imperial (inch) verses metric (mm) in the setup. Does it seem like Mach is multiplying by ~25? If your steppers are trying to go that fast, they probably will just growl.

Once you set the base units, and if you do have a 5 tpi screw (.2"/rev) and 1:1 drive, then 1000 should get you started. I would start with conservative velocity and accel settings, say 60 and 1, and slowly increase until response is unattainable (growling) and drop back 20 to 30%.

[ranchak]

1000 steps is correct for my machine. I thought the same about being in metric, but it's not. If I set my settings slow the motors growl, not fast. I didn't change anything in Mach other than pin settings, I guess I'll have to post on the Mach board and see what happens.

[nate]

Arent the G203V's 10X microstepping? so would that not be 10,000 steps per rotation? not 1,000.

[ranchak]

Nate, you're absolutely right about the 10X, also I have my motors wired at half step so I need to set my steps to 20000. Thanks, Ron

[Andre' B]

Originally Posted by ranchak Nate, you're absolutely right about the 10X, also I have my motors wired at half step so I need to set my steps to 20000. Thanks, Ron

For every motor and driver I have used the wiring between the motor and the driver is the same for full step, half step, or micro step.

[123CNC]

"MY MOTOR RUNS ROUGH AT LOW SPEEDs: Try adjusting the ADJUST trimpot setting. Verify you are using the correct CURRENT SET resistor (In your case, none required for 7A max.) A round stepper motor will not operate as well as a square stepper motor as they were not designed for microstepping." Gecko 203 V manual, italics my comment.

My experience has been pretty good, even with the old round NEMA 42s.

[HimyKabibble]

Originally Posted by ranchak Nate, you're absolutely right about the 10X, also I have my motors wired at half step so I need to set my steps to 20000. Thanks, Ron

Microstepping is completely determined by the controller. The motor neither knows nor cares that it's being micro-stepped, and the wiring is the same.

Regards,
Ray L.