Shifting on a gMax 2 Single Extruder

#1
Hey Everyone,

I am at a loss. My gMax 2 will not stop shifting layers mid print. Latest was a 35 hour print and it shifted halfway through. We are getting ready to just junk this machine because 9/10 prints fail. I have tried switching from Cura to Simplify3D. I have tries checking all electrical connections. I tried the trouble shooting for stepper motors.

What I honestly need to understand is my printer profile. I use Simplify3D, Atomic PLA, and I upload to my Astroprint cloud where I can monitor my print. Everytime I use Astroprint it says my printer profile doesn't match. I don't know what to do or where to go from here. I am an engineer trying to use this for some alpha modeling, I don't have time to become the 3D printing expert.

Here are some examples of failed prints from the last two weeks. Can someone tell me EXACTLY what to set up for Simplify3D in order to eliminate this problem?

Thanks
Tyler

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sp0d

New Member
#2
Just a heads up that you aren't alone on this issue. We had to fight layer shifting on our 1.5XT+ as well. The good news is that we did manage to get our layer shifting in check, and hopefully it will only take one or two small tweaks for you too.

I have a couple of questions to try and narrow down on the issue.

1. Are the shifts always along one axis, or is it along both X and Y?
Your photos make it look like this is isolated to a single axis but want to check.​
2. Are you using the upgraded heated bed?
(I.E. Did it come with the plexi that you switched over?)​
"I am an engineer trying to use this for some alpha modeling, I don't have time to become the 3D printing expert."

I feel your pain here bud. Our engineering team also had the aspiration that purchasing one of these machines would result in less maintenance and more of a turn-key solution for our team. Unfortunately, most if not all sub $25k 3d printers will require some level of printer maintenance understanding to keep the machines reliability up. (Hopefully you have someone on your team that will want to learn or grow in this area and take the pressure off you.)

Once you get those questions above answered let's dig in to see if we can quickly solve this annoying issue.
 
#3
We had this challenge as well.
How we fixed it:
1. download updated CURA 4.4.1
2. install the gmax 2 files from gcreate (they've posted new gmax 2 profiles)
3. Slow the print down.
4. Try to have enough filament for the entire print.
Good luck.
 
#4
Make sure the vref on the stepper driver for the axis having problems is correct. On my gMax 1.5+ machines the X axis runs around 0.7 to 0.8 volts and the bed is 0.9 or 1 volt. Also, a bad control box fan can cause the drivers to get hot and lose steps.