Z-gap issue while printing: it keeps changing during printing while using GRM heated bed

[rafael...@uconn.edu]

I have a GRM Heated Printbed, and have followed the suggested modifications from here: http://cubex3dprinting.blogspot.com/p/heated-printbed.html.

However, the same problem continues to persist.

As the bed moves down, and the printed model grows taller, the z-height is getting messed up. It slowly moves farther and farther away from the print until it starts spitting filament into thin air. After a while, it catches up with itself, and starts printing nice close layers. But then the print head slowly starts to move farther and farther away from the model, until finally it happens again. I've attached a recent print that shows the issue perfectly.

This happens no matter what print settings are used (any layer thickness, any density). The height however seems to be changing. Before I tried the fixes suggested in the blog, it was happening at about 1cm high. Now, after the fix, you can see it starts higher up.

Images of failure:

Earlier that print:

[CubeX 3D Printman]

Hello Rafael,

Just to double check, is your printbed heater cycle time set to 3? The relay in the heater controller should click every 3 seconds.

 

Are you using the CubeX software or Kisslicer to create the printfile?

When you look thru each layer in the slicing software, does each layer look ok and even?

 

Check if the set screws in your z-motor to z-drive spindle coupling are tight and that the motor mount is tight.

 

Is there enough strain relief in the cables for the heated bed so it can move freely up and down?

 

Double check the mounting for the heated print bed is solid.

 

Check if your print jet is mounted tight.

 

Have you printed some other parts successfully before? With standard print bed? With heated print bed?

 

 

 

Rick

[rafael...@uconn.edu]

Hi Rick,

Yes, I set the cycle time to 3, and it clicks just like it should.

I was using the CubeX software, but am currently running one print using kisslicer (already looks really nice), to see how things go. But the layers looked even for all prints I tried.

I'm extremely new to 3D printing. My club at school just had this printer donated from a company nearby that already had an extra laying around. The heated bed was already installed when we got it.

I've checked the mounting, and it feels solid. It is screwed in, so I'm not sure what I should be looking for. There is definitely enough slack in the cables going to the heated bed.


As for printing anything successfully, yes. Twice. But they were both too short to have noticed this problem...or maybe they just had good print files. Again, I'm really new to this.



I really appreciate the help,
Rafi

[kcha...@gmail.com]

> Earlier that print:

Hi Rick,

I'm new too and am just about to try the Kisslicer method. But, have you tried to print using one of Cubify's taller sample file, e.g. train_whistle.creation or rocket.creation. I had problems with the printer and on support's advice tightened up the z=axis set screws, as mentioned previously and then opened the rocket.creation file in Cubex.exe sliced built a .creation file and then printed it on my Cubify Trio and it printed perfectly! I haven't had much luck with printing my own creations and that's why I'm going to try Kisslicer. For 3D software I've tried 123D, Sketchup, Solidworks and Geomagic Design. The last one was recommended by Cubify support. Geomagic Design was bought by 3DSystems and even using that software the .stl export had some print issues use Cubex.exe. I find it odd that the sample file from Cubify will print perfectly but anything else will not. Geomagic .stl export has printed better using Cubex.exe but I not really wanting to spend another $1300 on another 3DSystems product.

Also, I found that leveling the bed and setting the z-gap is absolutely required to get good print jobs. I there a post somewhere about leveling the bed and in it was level_lines.cubex. This little file really helped me get the bed level first and when the output was even then I could adjust the z-gap. That helped me get the rocket.creation file to print perfectly. To my surprise.