I’m toying with adding pen plotter capability to my MPCNC Primo. My table isn’t perfectly level, so Z can vary and that causes pens to drag and skip.
It seems that most plotters out there use a spring mount for their pens to ensure this doesn’t happen. There are a few MPCNC mounts that do this but they depend on taking just the ink part of the pen, and if it doesn’t fit the spring mount, then it slips through the spring and doesn’t function.
Is there a spring loaded pen mount for a Primo that can take the whole pen without disassembly for pen plotting usage? There are a bunch of different pens and other plotting drawing tools out there so I’d like to have the option to use whatever size pen within reason. It would be great if it can fit in a Makita router mount but if I have to remove the router mount that’s fine.
so I think i am going to be using a tempered glass as i want to do the same thing. I did in fact surface, but after a few through cuts, it is now not able to be used with pen. I think glass will be best, you can tape to it, and heavy enough that it will not move and not need clamped down.
My spoilboard is some kind of particle plywood or chipboard that was part of a packing crate. I don’t think it’d stay surfaced if I did, and for the moment I was hoping to keep it at simple basic stuff to proof-of-concept the plotter. Plus for the plotter I was just working with the table on which my MPCNC is built since it’s relatively flat and even (at least with maybe a 1mm delta in Z thanks to the Z sizes of the conduit I cut for the MPCNC).
It’s a good thought if I ever find spoilboard that would more reliably stay level.
Floating pen holder with a weight instead of a spring works well for greatly varying Z. Might give up a bit of XY precision though… I’ve only ever used with markers and paint pens, so has been sufficient.
I know @vicious1 made a pen holder for the LR4 that works well in Z up and down while maintaining good XY accuracy. I’m not sure if he ever made one for the Primo though but might be worth checking Printables. Worst case you can see how he made the one for the LR4 and maybe get inspiration for your own version for the Primo.
Another note for the surfacing. If you have any MDF laying around that will fit the size of your spoilboard, you could screw that down and then surface the top of that to give you a nice smooth surface to plot on.
I definitely don’t have any MDF lying around - closest I have is that not-so-great particleboard or a wall mirror which definitely has an upward bend somewhere. Plus my MPCNC workspace is around 600x400, so I’d have to buy a pretty big chunk of MDF.