Crazy Z axis idea

Mostly Printed CNC - MPCNC Hardware Development
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Been a while since I been on the forums, house fire happened in early November and moving had not helped as it took away work space lol the good news is my Primo is fine as it was in garage! So i had worked with it a bit and had issues with chatter and struggled with the Z axis as expected it would need tuning. Sadly back to the fire my 3d printer was lost tho just an Ender 3 and Ender 3 Pro I had ventured into the Voron path as I had planned for that early on anyways. Working with Klipper has opened up a few ideas so we will leave software approach to a different day. Today we takle the Z axis!

So in theory has it been though of to take an approach similar to the LR but adopted an idea from the Voron 2.4 with 4 corner z axis? I know it may seem like overkill lol would be easier using a board for just Z with 4 end stops but what if we treated it like the LR? With parts keeping legs pretty square in theory 0,0 and Max,Max corners could be given an endstop and could run 2 steppers in series. I only thought of this as I have a Rambo which since Ryan has sent me has been a tank, I noticed it was setup for dual Z tho I am unsure on the situation of running 2 in series and both those output would be wise I figured amperage wise would level out granted its moving more weight upward than normal gravity would assist plunges into workpiece.

this would give the change to possibly make a more rigid core with tool mounts being directly mounted reducing the jitter. Mainly I used my Primo for audio boxes so it was not doing a lot of work on height, but I had issues with some bit types and chatter in wood granted I blame Dremel for crap bits at 1/8 shank lol. The most complex my uncle and I plan to get is guitar bodies and we really only need 4" of workspace but thinking going 2" x 4" for it to do whole neck as well with some designs. The weight of the core would not be lightened much I know but the little it is may help prevent bowing yes? I believe I did the smaller tube for the primo not anticipating this idea from my uncle, also not expecting the box for my wifes 15" sub to go over my 23.5 inch work space on all 4 sides XD so I figure an expansion would be a huge help tho to be fair 2 x 3 may also be enough I thought the possibility of solid core like the LR may greatly improve the primo. Also if we managed to klipper setup the 4 z axis setup would be a way to ensure squareness to table too but different theory for a different time lol

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Wow so sad to hear about the fire!!!

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So sorry to hear about the fire.

It sounds like you’re suggesting moving the whole cross member piece up and down by lifting at the trucks? I don’t think that is a huge problem from an electronics standpoint. 4 motors in series is probably too much. Either a 6 driver board like the skr pro, or you don’t use dual on x and y.

Lifting that much more weight seems like an awful lot of extra weight moving, and extra parts (4 leadscrew, motors). The core would be more rigid. But whatever you made the Z axis out of would still be flexible. The LR does a good job, has two tubes and two Z motor assemblies. There are still 4 vertical tubes on the LR too.

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Thanks guys could of been worse so taking the silver lining where i can lol.

I figured the added weight would be pretty extreme, was thinking of the benefits like Z homing and possibly tool change using mounted sockets and servos but even those would require a good deal of engineering. Where as I could always extend 1 axis and leave a small spot to springload connection to make true zero.

I planned on working on configurations for Fusion360 where from what i have gathered you put in stock specs and can position the 3D model inside of it. It then creates the cut out and gcode from that information all above Z0. I had attempted tool change mid cut before but had issues as I have no screen yet on the Primo :sweat_smile: it often had me thinking of ways to tool change without harming the cores stability.