An Alternative Extruder-Base Alignment Procedure for FlashForge Creator X


Bad Print 1

Figure 1. Bad area on bottom.

I’ve been having a lot of fun printing prototype pieces for a potential high altitude balloon box (more on that another time). Unfortunately this is a lot like the old days, when printers replaced typewriters. As I made corrections to a document, I’d reprint it. WYSIWYG was not really any help. The paper copy was always a little different. Suddenly I could go through reams of paper perfecting a small document. Unfortunately, I use my 3D Printer the same way, exploring new ideas and finalizing fits.

I’ve been using my FlashForge Creator X for about three weeks. I did an initial alignment, and since that time, before this week, I’ve replace the Kapton(tm) base once and realigned it. I’ve adopted the practice of wiping the Kapton(tm) with acetone before each build, and running the plate at 110C to 115C. And when building pieces that take up most of the plate, I tape a sheet of paper over the front opening, to try to get the plate temperature more uniform. I’ve had pretty good luck with things sticking to the base. That ended earlier this week after I replaced the Kapton(tm) tape again. After that alignment I had lots trouble with things sticking to the plate. This showed up especially clearly when printing the raft for a large piece, Fig 1,2. Part of the raft looks good, but other sections, instead of a nice straight line, looks jagged instead. Also Overlapping layers don’t stick, and instead of being square and perpendicular, looked more like narrow triangles. The strings vibrated as the print head moved because they were not attached. I tried several realignments and while I got the ‘good’ section to move, the “bad’ section moved to compensate.

Bad Print 2.

Fig 2. Bad area on left.

Now, I think there were some hardened strings hanging from one of the print heads making my alignment a little high.

Today, in desperation, I looked for the directions, and found three interesting pages.

Maintenance

Alignment

Jog

 

I noted three things. 1) I should periodically be cleaning the print head. This time I detached it from its mount so I could look at it and see what I was doing. 2) The alignment should be done hot, especially for ABS. 3) The “jog” mode in the utilities menu lets you move the head around. Unfortunately this does not let you move to specific coordinates. There is a need to first move the system to the home position to get to z=0.

If I were designing an alignment procedure, I would position the head above each adjustment screw to set the height, then verify it at several test points.

  1. use Preheat procedure to warm the plate.
  2. Use home procedure to send heads to [0,0,0]
  3. use jog to position one of the heads above/near each adjustment screw.
  4. Adjust the height (with pliers or gloves, the adjustment knobs are hot!)
  5. After all heights are adjusted,
  6. run utilities alignment program to verify alignment.

 

Following these steps got to where things are working 🙂 , Fig 3!

Good print

Fig. 3. Good print, after alignment.

The procedure should lower the base before moving, as the installed alignment program does, to prevent the possibility of scratching the base as the heads move across the surface.

 

© David B. Snyder, 2014

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