Late 2022 I was visiting a metal and electronics recycling facility and saw something shiny that caught my attention.
It was an industrial pick-and-place machine that needed some love and attention. Nothing but top-grade components inside. Since the whole machine was too big and too heavy to fit in my makerspace, I have harvested its components and been fiddling with them ever since.

What could I be doing with these monsters? The machine has two, and I was lucky to get an option on a third. With three more, I might be able to create a fun “little” Stewart platform. For driving it, I am considering either a Leadshine 2Nm three-phase closed-loop stepper or a 180W JMC servo. It’s still to be decided which of the two it will be. I might just revert to a NEMA23 stepper motor since I already have it in stock.

One of the bridges I’ve been using as a super-stiff bridge for my homemade CNC machine. I am now investigating if I can use the linear motor for CNC purposes, although it would make it impossible to mill ferrous materials. Creating controls for the linear motors seems like a daunting task, but “because you can” is reason enough to give it a try. I will definitely not be in the same room as the linear contraption, because the potentially achievable accelerations advertised in the specs give me goosebumps. Just a three-phase H-bridge and a feedback loop, can’t be that hard to make with an STM32 controller, LOL.
On the original bridge, I found an optical sensor with 1-micrometer accuracy. It’s probably too sensitive for my needs, so I will place one or more pulse dividers to slightly tame the incoming signal. I should be careful in the beginning with the voltage and maximum amperage on the linear motors, as it might become a cannon if not treated gently.
The Metrology research project has also a lot to gain from the new bridge. I might make it a universal machine combined with a CNC function.

I am not yet happy with the stiffness of my Stepcraft 840, pictured below, and I think that the new bridge should perform much better. Even if I only use two leadscrews in unison, it should outperform what the Stepcraft offers. I need to properly dimension the motors so I can maintain the accelerations and feed speed necessary for proper milling operations in 6061 aluminum. Probably in the end I will only keep the spindle and the t-slot table.

Leave a Reply

This site uses Akismet to reduce spam. Learn how your comment data is processed.