Preparing to 3D Print

Preparing to 3D Print - Setting Yourself Up for Success
Preparing to 3D Print - Revision 4 - 17/10/2020 - Chris White

 [Document in Draft Edit] 

These steps describe how to setup your DexArm for best 3D printing performance.

Rotrics Spool Stand
Using the supplied Spool Stand can be a little tricky, but hopefully these little guides can help make it work until you upgrade to a larger spool holder.


 * 1 - Make sure the bearings are free to roll. If the nut and bolt that secures them is too tight, then the bearing movement will be restricted. Consider replacing the nuts with Nyloc nuts as these will offer great resistance against vibration.


 * 2 - Ensure the spool holders are used the correct way round. See the below diagram for assistance. The larger face should be on the inside, and the shorter face on the outside.


 * 3 - Remember not to let go of the end of the Filament. Ensure it is pushed through the holes in the side of the spool itself. If you do let go, the filament can become tangled.

Component Layout
Placing of the components within the 3D Printing System is important for best results.

The main principles are: -

Minimum Bending of the Bowden Tube - Friction created in this tube will affect print quality if it is too high. So keep bends as smooth and gentle as possible. A long Bowden Tube can also be a factor, the longer the filament spends in the tube, the greater the friction on any curves. The supplied Bowden Tube is probably the longest you should have (70cm max), so any new Bowden Tubes will need to be made shorter unless your setup permits long straight runs.

Extruder Back-Stop / Clamping - As the Extruder pulls filament from the spool, science says it ways to be drawn towards the spool ("Every Action has an Equal and Opposite Reaction"). So it is important to either clamp the Extruder to your work surface or provide something that the extruder can push against without hitting the spool.

Bowden Tube Installation into the Hot End
Correct installation of the Bowden Tube into the Hot End is important. Because the Bowden Tube guides the filament into the hot end. If this tube is not pushed down far enough into the hot end, you can experience clogging and jamming. Filament will bend as it gets warm inside the hot end, and eventually curl and become solid as the extruder tries to push more and more filament into the hot end.

The illustration below shows the two cases. The left, where the bowden tube is pushed down inside the hot end - guiding the filament to the centre of the nozzle. On the right, the bowden tube is only inserted halfway into the hot end - opening risk to jams, clogs and other issues.