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An over engineered, but still not perfect, pressing pen holder for the Creality CR-10.

With the rubberband in place the pen will always be held down even on uneven materials that are being plotted.

The best part is that there is no need to remove any existing parts from the printer since the upgrade attachs to one of the fans with 4 M2 screws without interfering with the extruder or any other parts.
Printing as usually will be no different with the upgrade in place.

23-02-2018// I will mount and test this in the morning.

Edit: Improvements that can be made are: Remodelling penhallare to fit a 6 mm linear bearing in it and switch the rubberband for a spring, much more reliable that way. However, I did not do this since few have linear bearings laying around and I wanted as many as possible to be able to print this and try it out.

Update: I have now tested and confirmed that it works, but I do have some wiggle on the Y-axis. This problem would be eliminated with bearings. Nothing collides in full travel area.

Update 2: Added nested pen holder for those who only want to print on paper. Less parts, no bearings.

See further information for part list.