Motors wont turn same old same old

Ok so I have been working on building a 3d printer for the past few weeks, I have finally finished off all of the hardware and am working on getting the electronics to work correctly... like getting the motors to move. So here is my problem I hook my x axis motor into its driver and tell it to jump a little but it doesnt move at all (I took the belt off so there is no resistance on the shaft, and the pot on the driver is set to around 0.5v) instead it just makes a hum, so if I put my hand on the motor shaft and turned a little while I tell it to jump it will jump with assistance. So I figured okay maybe it needs more power same thing happens except it needs a little less effort to move. I then figured it would be easier to debug the motor if I put it on the extruder driver. Set it to extrude for awhile in printrun and the motor will move slowly. So I decided to change the value of mm/min and the motor speed was the same. I put the belt back on and it wouldnt move the carriage which I figured so I decided why not and upped the voltage on the pot but no movement just an assortment of noises and everything got really hot so I just it off. I dont think it can be a power problem because when the motor is activated you cant move it atall just when you tell it to jump. So I'm not sure whats wrong, if any of you reprap sages care to lend a hand I'll be very appreciative.

I was playing around with the motors and found something weird. If I tell the x motor to jump backwards or reverse it wont go that way and if I hit the x forward after that it doesnt move it stays in the same place but the x value coordinate goes up, If I go past this value in the postive direction so say I told it to jump right twice then it will try to jump but again will not turn unless I assist.

You may have a firmware issue with endstops. You can use M119 to query the status of the endstops. If any come back High (H) you'll need to adjust firmware to match your endstops.

Also it would help if we knew what drivers and motors you are using. What is the max current of the stepper? What is your driver supposedly outputting at 0.5V? Not all "Pololu's" are the same as there are a lot of clones out there.

Is the stepper locked tightly in place when the current is on? If not you are likely not driving with enough current.

Bryan

Well I just tried disabling endstops in the firmware i'm not sure if that would have fixed the problem but I tried it and it didnt seem to make any difference. I also tried manually switching the endstops as well but no dice. I kept hitting the jog and every once in awhile it would move one step so I thought that was weird. I tried changing the voltage to see if a higher value would change anything and it aswell did not change anything it just makes noises. Is it normal for the motor to just make a constant wine while it has a current applied to it? Btb i am using ramps 1.4 and Allegro's A4988 DMOS Microstepping Driver. the motors say that they are 12-36v and up to 1.2 amps.

Have you checked the wiring?.

Post your motor datasheets.

Edited 1 time(s). Last edit at 02/27/2014 08:28AM by tjb1.

I agree with tjb1. Make sure that each coil is paired on the letter not the number. If you have ramps 1.4, one coil goes on 1A and 2A NOT 1A and 1B. That was my mistake.

Edit
I just made the same mistake trying to inform you of my mistake. It SHOULD be 1A and 1B and 2 A and 2 B.

Edited 1 time(s). Last edit at 02/28/2014 08:59AM by jtoombs.

When I wired my motors I checked to see what what two wires had the most resistance on them and cut the center tap, on the motors the wires are all blue except for the two center taps which are orange, so i cut those off. I then put the two wires next too each other in a 4 prong connector. I wired it so that the outer wire on the motor connector is the outer wire on the 4 pin connector.
PIN1= B-
COMMON
PIN3= B
PIN4= A
COMMON
PIN6= A-

So right now I have it wired that B- will be the outer most wire B+ and A+ are the inner wires with A- on the outside aswell. Is this wrong?

Quote
tyscof
When I wired my motors I checked to see what what two wires had the most resistance on them and cut the center tap, on the motors the wires are all blue except for the two center taps which are orange, so i cut those off. I then put the two wires next too each other in a 4 prong connector. I wired it so that the outer wire on the motor connector is the outer wire on the 4 pin connector.
PIN1= B-
COMMON
PIN3= B
PIN4= A
COMMON
PIN6= A-

So right now I have it wired that B- will be the outer most wire B+ and A+ are the inner wires with A- on the outside aswell. Is this wrong?

Datasheet?

I don't have a datasheet since I bought them off of ebay but here is the link to the motor, Ill ask him for a datasheet.
[www.ebay.com]

Ramps

(2B )(2A)(1A)(1B )

You need to wire as follows:

(2B = 1)(2A = 3)(1A = 4)(1B =6)

or

(2B = 3)(2A = 1)(1A = 6)(1B = 4)

I think that is correct from what you provided. The numbers following the 1A, 2A, etc are the pin numbers on the motor. Numbers on RAMPS are the coils. Steppers have no polarity so do not worry about that.

Edited to adjust for Ramps numbering/lettering, should be correct now.

Edited 4 time(s). Last edit at 02/28/2014 09:12AM by tjb1.

Wait... I think I provided you with the wrong information. Now that I looked at my ramps board I realized that I had it wired up so that one coil was on the inner two pins and the other was on the outer two. This is wrong on the ramps board. It should be the pins that are next to each other are each a coil. So 1A and 1B and 2A and 2B go together. It was really confusing to me at first . I probably spent a good two days trying to figure out that this was my problem.

Quote
jtoombs
Wait... I think I provided you with the wrong information. Now that I looked at my ramps board I realized that I had it wired up so that one coil was on the inner two pins and the other was on the outer two. This is wrong on the ramps board. It should be the pins that are next to each other are each a coil. So 1A and 1B and 2A and 2B go together. It was really confusing to me at first . I probably spent a good two days trying to figure out that this was my problem.

I edited my post to account for this also. I haven't been home to be able to check mine.

Edited 1 time(s). Last edit at 02/28/2014 09:14AM by tjb1.

Okay so then I do have my motors wired correctly, I have them as pins order 1,3,4,6. I have the two wires for a coil on one side and two wires for the other coil on the other side. I checked the voltage the motor was getting to make sure and when I put my meter over the two leftmost wires(B+ and B- or wires 1 and 3) and got a voltage of 12.8 and the same when I put it over the other two wires. So could this be a problem with my drivers or board? I don't think it could be my drivers because none of them work but I don't know if that really means anything. I guess we could safely assume the motors are getting enough amperage and that wouldn't be the problem, unless the shaft not moving may indicate that, but it isn't turn able when there is a current on it. It also can't be the motors since all 5 do not work, would the endstops be causing this? I just unplugged them since they were in the way but that shouldn't matter if I'm just jogging the motors right? It should't make a difference with the extruder driver anyway which tries to move but is super weak and can't.

Quote
tyscof
Okay so then I do have my motors wired correctly, I have them as pins order 1,3,4,6. I have the two wires for a coil on one side and two wires for the other coil on the other side. I checked the voltage the motor was getting to make sure and when I put my meter over the two leftmost wires(B+ and B- or wires 1 and 3) and got a voltage of 12.8 and the same when I put it over the other two wires. So could this be a problem with my drivers or board? I don't think it could be my drivers because none of them work but I don't know if that really means anything. I guess we could safely assume the motors are getting enough amperage and that wouldn't be the problem, unless the shaft not moving may indicate that, but it isn't turn able when there is a current on it. It also can't be the motors since all 5 do not work, would the endstops be causing this? I just unplugged them since they were in the way but that shouldn't matter if I'm just jogging the motors right? It should't make a difference with the extruder driver anyway which tries to move but is super weak and can't.

The extruder shouldn't move unless you have cold extrusion allowed. XYZ won't move correctly unless homed, they will jog one way but not the other and sometimes weird things can happen. Have you set steps correctly? You really can't just any motor movement until you have the steps set because you are sending a length of unit for the motor to move and with the steps incorrect, it may not appear to work correctly.

Ok the motors not moving in reverse makes sense now since they are not homed, and No I havent messed around with the steps per mm, in the firmware right? I could see how that would throw off accurate movement but shouldn't the motor still move just the wrong distance? Like if I jog the motor 100 units or connect it to the extrusion driver it should move just not say the exact 100 units right? Or would this stop the motors from doing anything?

Quote
tyscof
Ok the motors not moving in reverse makes sense now since they are not homed, and No I havent messed around with the steps per mm, in the firmware right? I could see how that would throw off accurate movement but shouldn't the motor still move just the wrong distance? Like if I jog the motor 100 units or connect it to the extrusion driver it should move just not say the exact 100 units right? Or would this stop the motors from doing anything?

What I meant is what you see is likely not what you are expecting, set the steps and check again.

OK so we have movement! I change this value which I think is what I was supposed to,
it was this #define _AXIS_STEP_PER_UNIT {80, 80, 3200/1.25,700 and
I changed it to this }#define _AXIS_STEP_PER_UNIT {10, 80, 3200/1.25,700}

I went on a online calculator and it said to make it 80 [calculator.josefprusa.cz] but I found the lower I set it it would move so I just set it to 10 and found that it started moving, the question is what value I will need to set it at since the calculation doesn't seem to work(ill try again) I tried it at 53.3 and It wouldn't move either till it got down to around high 20's. A problem I have now is that If I jog right it will go right then hit a point and jog back left even though I hit jog right and then will keep going back and forth. Is this because it is not homed yet? Nd how do I set home? I don't see it anywhere.

Edited 2 time(s). Last edit at 02/28/2014 12:22PM by tyscof.

Did you set the vref?

Yep, I set them to around .5 which is right for my drivers, It seems like the y stepper is working great still having trouble with the x now it doesnt want to move again even with the
#define _AXIS_STEP_PER_UNIT {10, 30, 3200/1.25,700} set super low. And if I tell it to move now I can just push it without very much effort even if the vref is set really high, so I think I may have burned it out or it was deffective to begin with, or it may be fine and I messed with it enough in the firmware to set it screwy again. But I think something is wrong with the motor since if I set the x and y axis motor to the same setting the y axis one works well but the x doesnt move at all. And get this when I set the y motor to 53.3 in mm/s it moved fine so I guess the x motor has been deffective all along? I have a question though, in pronterface if you hit your endstop does it say anything in the commands window because when I plug them in they dont seem to do anything, I have it wired so that it is closed with a 4.7kohm resistor connecting the ground and singal wire, when the end stop is hit the circuit is open

Quote
tyscof
Yep, I set them to around .5 which is right for my drivers, It seems like the y stepper is working great still having trouble with the x now it doesnt want to move again even with the
#define _AXIS_STEP_PER_UNIT {10, 30, 3200/1.25,700} set super low. And if I tell it to move now I can just push it without very much effort even if the vref is set really high, so I think I may have burned it out or it was deffective to begin with, or it may be fine and I messed with it enough in the firmware to set it screwy again. But I think something is wrong with the motor since if I set the x and y axis motor to the same setting the y axis one works well but the x doesnt move at all. And get this when I set the y motor to 53.3 in mm/s it moved fine so I guess the x motor has been deffective all along? I have a question though, in pronterface if you hit your endstop does it say anything in the commands window because when I plug them in they dont seem to do anything, I have it wired so that it is closed with a 4.7kohm resistor connecting the ground and singal wire, when the end stop is hit the circuit is open

The motor will move less the lower the steps are.

1.8 degree motors have 200 steps, you are telling it that it needs to move 10 steps to move 1mm which would only move 18 degrees.

Ok so If I set my #define _AXIS_STEP_PER_UNIT higher like to 100 the smaller step like.1 works fine but when I try to hit 1 it just makes a high pitch noise and doesn't move. I set it to 100 because when I set it to 50 it took two hit of .1 to get it to jog once, but say if I try to jog 100 the y doesn't move it just makes a loud high pitch noise, know any cause of this? Likewise if I set it lower it can do the larger jogs but I have to hit the .1 jog like 50 times to get it to move anywhere.

Edited 2 time(s). Last edit at 02/28/2014 06:54PM by tyscof.

Quote
tyscof
Ok so If I set my #define _AXIS_STEP_PER_UNIT higher like to 100 the smaller step like.1 works fine but when I try to hit 1 it just makes a high pitch noise and doesn't move. I set it to 100 because when I set it to 50 it took two hit of .1 to get it to jog once, but say if I try to jog 100 the y doesn't move it just makes a loud high pitch noise, know any cause of this? Likewise if I set it lower it can do the larger jogs but I have to hit the .1 jog like 50 times to get it to move anywhere.

Turn axis acceleration and speed down very low, you can raise them up later.

Do you mean this:
#define _ACCELERATION 1000 // Axis Normal acceleration mm/s^2
and this:
#define MINIMUM_PLANNER_SPEED 0.05 // (mm/sec)

what should I set them too?