Is this problem caused by makerbase quality, my 3d printer or solely my settings.

[david sköld]

The last couple of weeks i have been struggling with the makerbase closed loop steppers. On top of the wavy walls due to pid settings i get a very distinct ripple effect that follows the speed of the steppers. No matter what i do i cant seem to get my print quality even close to that of my previous steppers. I have not yet seen closed loop steppers on a delta printer, which could be a reason for the bad results. I have tried tuning the steppers pid values on a very wide range and the ripple effect is the same at all settings. It seems as if the problem is constant no matter what i do. If i could figure out if the problem originates from the steppers i would be happy to order the real ones from misfittech. I'll try and add some pictures after work so that it is clear what i am talking about

[misfittech]

Usually it is caused by the PID parameters not set correctly and causing ringing.  Have you tried tuning the PID parameters? 

[david sköld]

I have been trying different pid settings for a while now and have gotten a fairly nice result. The thing is that while the walls print smoothly there is still a deviation in the smooth walls. Its as if the controllers almost make fewer steps at these points. Or atleast too big jumps between steps. They show up on prints where one or two steppers move really slow. I actually hope that i could solve this by bying your products but i want to be certain that it is the servo42s that are doing this. It would be a real bummer if i bought your controllers and the problem persists.
As i wrote earlier i will try and get some pictures for you in a couple of hours.
Maybe this is a good thing. If it turns out that the problem is the hardware then it would be a very good reason for people not to choose makerbase.

[david sköld]

the first picture shows the deviation on one side of a triangle. the deviation is equal on all sides. the triangle is printed so that each side of the triangle is facing one stepper motor 90 degrees. the pattern differs between layers because i was trying different pid settings.

the second picture shows an items printed with ordinary stepper motors and drivers. i am going to try to increase and decrease microstepping to see if it has anything to do with the small amount of steps one motor is taking each time it reaches a near halted position.

[Ed Simmons]

I know this is an old thread, but you should definitely try increasing the 5v supply voltage a bit, maybe to 5.6-5.7v and you should see these ripples disappear.

[david sköld]

Thank you very much for your reply. Even as this thread is old i feel that this thread is still relevant. After i started this thread, several of my coworkers have purchased cartesian printers where several of them have shown similar artifacts. I find it more reasonable to experience this with a delta printer since there is seldom more than one motor standing still. Cartesians should as far as i understand, only show these artifacts in certain angles. When i find the time i will look into increasing the voltage to the steppers. I run a trigorilla board and havent yet figured out how to do this.

[misfittech]

The ripples can be caused by multiple things including:

1. Noise on the power lines  

This happens because the long runs of wiring and not twisting power wires going to stepper boards, etc.  Increasing VCC increases the amount of noise before false triggering and such as such it might help. 

2. Poor Configuration

The PID controller parameters are critical, that is when motor is stopped you do not want the motor to oscillate around the set point. The simple PID mode in the smart steppers can help with this as that in the simple form when the motor stops it switches back to stepper motor mode instead of PID to remove oscillations, among fixing other issues. 

3. Poor mechanics

As the motors move any backlash can cause some ripples in the print, loose screws etc do the same. 

4. Bad Motion Controllers

Many of the motion controllers do not have the math implemented correctly and causes rounding problems which causes ripples. Others have poor acceleration code that causes errors, especially if you are using a corexy type of machine. Often these problems appear depending on the rotation of the part being printed.  

The noise on the power wire are by far the biggest one for smart steppers just due to the long wires.  For debugging this people often put large capacitors at each smart stepper and see if the problem improves, if it does then most likely you have power line noise issue.  Also increasing motors to run off higher voltages (24V or 36V) makes a big improvement. 

The smart steppers generate the processor power from the motor voltage, where maker base does not. As such maker base boards are more sensitive to the 5V supply issues where the smart stepper should not be.  

Trampas

[Markus Gutendorff]

[Markus Gutendorff]

Did you get your motors to work well? Kind of in the same situation as you. I'm a swede also

[david sköld]

Yes i did. Kind of. 

Ar first there was alot of ripples on the surface of the print. I managed to lower the ripples by tuning the pid settings. I work in heating and ventilation where pid tuning is common. The difference here is that it is almost impossible to get a perfect tuning because of varying speeds during a print. As an example - we can look at a common PID-tuned motor, the ventilation fan motor. The motor has a load that does not change over time since the only load is the fan blades. In my experience a motor will always oscillate to some extent if the motor has a varying work load. Depending on what you want to do with your motor, the pid tuning varies alot. A delta printer for example requires a lower torque than a cartesian printer.

I digress

As trampas wrote, the having a wavey surface can also be a result of a power dipp.

Yesterday i noticed that my LED lamp had started to flicker, witch made me think that it was about to blow.

Later i noticed that the flicker followed the heating pulse for my hotbed. I only recently added the light to my printers common 12v source.

In my early printing days i realised that the printer would brown out because of insufficient power witch made me purchase 2 separate beefy  powersupplies. One for the hotbed and one for the rest.. now that both of these power supplies are connected together one would not expect that the fluctuating light from my led would be the result of low power. Although. It is. Therefore i suggest that you try printing a simple 3x3 box without heating the bed.

If your print improves then you should definatelyy look into separate power for the big consumers in the printer 

Since you will never be able the adjust the PID so that these fluctuations dissapear