Got my nimble! And it fits!
Finally. Got a working mount for the Zesty Nimble on SeeMeCNC's HE280/Rostock Max v3 hotend/printer.
I made a few designs before... each one realizing it interfered with something that i didnt have modeled. and another where i just made it too tall.
Anyway, here it is, step file included, once i get my nimble ill test fit it and post pics too.
Solidworks files available on request, but its a jumble of parts combined into assemblies back into parts/bodies, finally combined and cleaned up.
Best to print at .1mm layer height, pretty slow, and probably 100% infill.
Youll definitely want to print with support too. I set it pretty dense at 25% my first go at it. The bottom wont look the prettiest, but it will be hidden anyway.
Bad news. :(
I printed some new hats in April of this year... and one of them broke. :( I made it with some polycarbonate blend, i forget the brand. Either it broke from over-extending front/back from the flex drive's cable, or just fatigued from the same motion.
Maybe ill reinforce the hat. maybe ill just try a different material.
My nimble finally retracts!
Follow the documentation for the nimble to get it to work. I had changed the max start extrude rate, but... i had lowered the current too much, and the stepper didnt work, soooo. Yeah. My bad. Had i not touched the current, none of this would have happened.
Added 3 more flies, this one with the hole for the PTFE tube to sit flush with the top surface, like every other nimble mount.
Originally i had designed it to jam the PTFE tube between this cover and the hotend, but hitting the exact PTFE tube length to prevent backlash/jams is hard. Cutting it flush is the better way.
I also have seemed to increase the STL export resolution/detail, so these recently uploaded files are much larger. FYI.
See 6June2017 for other info on bolt length.
I got my nimble today! Yaaaay.
And, the mount works! Yaaay.
Set your extruder steps/mm to 2640.
However... Youll need to cut the included bolts down to make it fit. Booo.
The threaded lengths will need to be... 33mm and 36mm (per the model, i never measured myself). PLEASE PLEASE, TAKE CAUTION WHEN DOING THIS. Take off a little at a time, make sure the shorter one doesnt interfere with the fan headers, and repeat.
PTFE tube to be cut at 48mm, and youll need to take a ~4mm drill bit to clean the hole up for it (and maybe a small one for the filament path).
ORRR... you can drill that straight through and trim the PTFE tube off at the top, like every other nimble mount. (making a model like that now too)
And... Currently, Repetier firmware (for those using it) does not support the required settings for the nimble, specifically a very low extruder jerk value (1 mm/s). It is calculated internally using the max start feedrate. I believe this should be easy to patch, but im no c++ wizard, and havent had the ambition to edit the few files yet. So stay tuned.
But, i did have my first successful print with it, its a nimble mount for the Rostock Max V2, which is still being made, just trying some stuff out.
After being unable to get my slicer to add supports as i wanted, i went ahead and added my own in solidworks. I ended up print half with my supports, half with slicer and while, mine took more time, they worked considerably better and snapped right off of the print with no need to scrape/clean up. So i painstakingly took the time to put supports under the rest of it. Ive attached 2 options, one with premade supports (for a .5mm nozzle), and another with the holes filled in so that youll get continuous support everywhere.
Done, for the final time, I hope. Will print tomorrow and test fit. Basically the same as before, just a bit taller so the nut doesnt interfere with the fan plugs. Depending on the length of the hardware that comes with the nimble, it may need to be ground down a bit, as there is minimal clearance there. But it should all fit.
I also changed how the PTFE Tube sat, now its held down inside by the cap, so getting it cut to the correct length is crucial.
Pics (besides the render) are of the old one that doesnt actually fit, oh well, same concept.
Printed tweaked version only to realize my model was still lacking and the piece interfered once i plugged the fan(s) in. ughhhhhh. Time for another full redesign.
Printed and I realized there were a few thin spots, so it will still need some tweaks. Its also a bit too short on top of the hotend/PTC bit, so that needs to be cleaned up (but its supposed to be tight to hold the PTC fitting down, so the nimble can apply pressure to the PTFE Tube). Will update later/soon. Hopefully they get shipped out soon so I can actually get a test fit and tweak the design as needed.
Basically, see this: http://zestytechnology.readthedocs.io/en/latest/nimble_single/tuning.html
Set your EXT0_MAX_START_FEEDRATE to 1 in the firmware or through the PC with the EEPROM, or through the display.
Same goes for the acceleration.
Set your retract distance and speed in your slicer.
For V_ref/current... This one you may want to leave as is. I lowered mine substantially and it didnt work. But ill try tuning this around soon. It currently makes tons of noise when running, then again... i just picked a random 170/255 on the digipot and it worked.