Thanks for the update, interesting results. Including the pen cap!!
Have you considered that it could be results of friction of the felt tip on the paper? Sort of a grab-then-release-and-catch-up motion? That would probably change with different paper and pen pressure.
Is this anomaly only happening on a “diagonal” line in which the X & Y axis motion is taking place?
It could be the material of the marker tip sightly flexing, meaning the tip starts straight then when the steppers move the tip maintains its relative direction until the motion pulls it in the direction change?
If that makes sense. The examples you provided seem to show straight lines for the letter outlines but the wavy line on the diagonals.
Does this behavior occur with a ball point pen or pencil?
I had not considered that, actually. I was thinking it might be the v-wheels or belts not being adjusted correctly. We have a couple of SO5 pros at work. Maybe I’ll try them both on the SO5’s and see what happens.
It may also be the pen rocking in the holder since there is only a single point pushing on it in the middle of the length between the tip and shoulder where the cap normally covers.
Maybe re-design the holder to distribute the force to a larger area if the SO5 test shows the same oscillations.
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Try drawing on some glossy paper or acrylic sheet to see if a more slippery surface changes the waves
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That’s a good idea! I determined that I am done with the pen design, and it is what it is - for now. I will get all of the files that are the latest revision and put them on Printables and Thingiverse, along with assembly instructions. I guess I should at least make a 65mm spindle version as well.
I am hoping to get it done in the next couple of weeks.
At some point, I will also make a SO5 PRO version that mounts with the accessory plate instead of having to use hose clamps around the spindle.
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Well, it appears I can’t leave it alone like I said I was going to. I ordered an MGN9 rail and MGN9H slider to see if the slightly wider rail and slightly longer slider help with the oscillations. Then I will be done for sure*.
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Maybe, who knows!?
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