1

Topic: New issue... Need some insight

Ok... some of you may know of my post from the Hack/Mod area
and that I have recently been trying to get my Azteeg X3 board
up and running since replacing my original board that shorted out...

SO I think I have the bugs out of it... and it is back up now and printing...
However, I am getting some strange stuff in my prints.

http://soliforum.com/i/?xoRmbv4.jpg

The top 3 objects were test prints that I did...
and you can see the strange spiralling that I
am getting in the prints.  The sides seem to be the
correct thickness and there is not layer separation.

Just a weird spiral pattern... I adjusted both the step count
for the extruder (to get the correct 100mm extrude) and
tried various layer heights (.120mm which a friend uses, and
.1976 from the prusa calculator).  The layer definitely changed
but the swirl still seems to be there.

After adjusting some more... the bottom 2 are the latest print...
and it still seems to have an issue... the outer surface just
does not look correct.

What is going on?  Do I axis that are not "tuned" correctly?  Something
loose on the machine throwing something off?  Over or Under extruding?

I am not sure... and I am chasing my tail....

Can anyone help?

Matt

2

Re: New issue... Need some insight

The spiraling looks like your extruder motor is pulsating. You need to play with the current limit to see if it clears up.

Printing since 2009 and still love it!
Anycubic 4MAX best $225 ever invested.
Voxelabs Proxima SLA. 6 inch 2k Mono LCD.
Anycubic Predator, massive Delta machine. 450 x 370 print envelope.

3

Re: New issue... Need some insight

How do I adjust that Carl?

Is that thru adjusting the pot for the extruder?

Just curious......

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Re: New issue... Need some insight

cujo3131 wrote:

How do I adjust that Carl?

Is that thru adjusting the pot for the extruder?

Just curious......

Each of your stepper drivers have a pot on them to adjust the current limit. I am assuming you went all out and got the DRV8825 drivers as well?

Printing since 2009 and still love it!
Anycubic 4MAX best $225 ever invested.
Voxelabs Proxima SLA. 6 inch 2k Mono LCD.
Anycubic Predator, massive Delta machine. 450 x 370 print envelope.

5

Re: New issue... Need some insight

I have the SD8825 stepper drivers with heatsinks

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Re: New issue... Need some insight

cujo3131 wrote:

I have the SD8825 stepper drivers with heatsinks

Same thing, DRV8825 is the actual chip on the driver. Go to Panucatt.com and look under those drivers and you will find a pdf that tells you how to set the current limit on them.

Printing since 2009 and still love it!
Anycubic 4MAX best $225 ever invested.
Voxelabs Proxima SLA. 6 inch 2k Mono LCD.
Anycubic Predator, massive Delta machine. 450 x 370 print envelope.

7

Re: New issue... Need some insight

Ok.... I see how to change and set the current.... how do I find out what current is best for extruder  motor?
It is the original extruder motor and has not been changed....

Matt

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Re: New issue... Need some insight

cujo3131 wrote:

Ok.... I see how to change and set the current.... how do I find out what current is best for extruder  motor?
It is the original extruder motor and has not been changed....

Matt


Adjust the current down to where the motor starts skipping then up a quarter turn usually gets you where you need to be. Then you can fine tune as time goes by.

Printing since 2009 and still love it!
Anycubic 4MAX best $225 ever invested.
Voxelabs Proxima SLA. 6 inch 2k Mono LCD.
Anycubic Predator, massive Delta machine. 450 x 370 print envelope.

9

Re: New issue... Need some insight

Would these settings from the multimeter test page for Solidoodle still be
accurate?????

Extruder: 0.192V (note: for Rev E Motherboards, the extruder voltage should be 0.770V)
X-Axis: 0.443V
Y-Axis: 0.520V
Z-Axis: 0.500V

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Re: New issue... Need some insight

cujo3131 wrote:

Would these settings from the multimeter test page for Solidoodle still be
accurate?????

Extruder: 0.192V (note: for Rev E Motherboards, the extruder voltage should be 0.770V)
X-Axis: 0.443V
Y-Axis: 0.520V
Z-Axis: 0.500V


No, you really need to get that PDF and read. These drivers are different from any other driver out there. The basic rule here, is your machine is no longer a Solidoodle and settings and options for it no longer apply. You have to read up on your parts now and set things accordingly.

Printing since 2009 and still love it!
Anycubic 4MAX best $225 ever invested.
Voxelabs Proxima SLA. 6 inch 2k Mono LCD.
Anycubic Predator, massive Delta machine. 450 x 370 print envelope.

11

Re: New issue... Need some insight

I did get the PDF.... it's 1 page....

And I read the whole thing.... including the section on current limit....

But what I don't know is my MOTOR’S CURRENT RATING....

So not knowing that, not sure what the PDF is really suppose to help me with....

Not trying to be dense or difficult....

Just trying to understand....

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Re: New issue... Need some insight

cujo3131 wrote:

I did get the PDF.... it's 1 page....

And I read the whole thing.... including the section on current limit....

But what I don't know is my MOTOR’S CURRENT RATING....

So not knowing that, not sure what the PDF is really suppose to help me with....

Not trying to be dense or difficult....

Just trying to understand....


A nema 17 is 1.7 amps.

Printing since 2009 and still love it!
Anycubic 4MAX best $225 ever invested.
Voxelabs Proxima SLA. 6 inch 2k Mono LCD.
Anycubic Predator, massive Delta machine. 450 x 370 print envelope.

13 (edited by grob 2015-06-18 04:21:16)

Re: New issue... Need some insight

carl_m1968 wrote:

A nema 17 is 1.7 amps.

Not quite. It's 1.7x1.7 inches haha. Different nema 17 motors vary in current quite a lot depending on a number of other things (e.g. there are long and short ones, the 0.9 degree ones are a bit different to the 1.8 degree ones, etc.). Somewhere between 1 and 2 A (including 1.7A, of course!) is reasonable.

Ideally you need the datasheet for your motor too. Given it's a stock solidoodle unit, maybe try the values from this table.

Using the datasheet for the driver, work out what Vref voltage you should set to achieve the motor current listed in the table for the relevant motor. Start there, then tune by ear if you prefer (I recommend this!).

Note that the relationship between vref and motor current is dependent both on the driver chip (the DRV8825 in this case) and the sense resistor used on the carrier board - hence why there are differences between some pololu-style modules even with the same driver IC.

SD3. Mk2b + glass, heated enclosure, GT2 belts, direct drive y shaft, linear bearings, bowden-feed E3D v5 w/ 0.9° stepper
Smoothieboard via Octoprint on RPi