I discovered that the factory Genmitsu controller runs GRBL 1.1 that is only able to support 3 axes and isn’t upgradable to any other controller firmware. So that meant I wasn’t able to use the expensive Rotary Table accessory I purchased with the CNC Router…that was supposed to work with it….and that I had many plans for…and was one of the main reasons for purchasing a CNC Router at this time. That started a huge plunge into a Black Hole of time and effort for what I thought would have been an easy fix. It actually would have been pretty easy from the research I had done to date but the solution I found was from a company (OpenBuilds) that just announced it was going out of business and the pre-made perfect controller I needed was no longer available. Yep, perfect BCBH (Black Cloud/Black Hole) convergence once again.
So surely other companies sell complete solutions like OpenBuilds, right? WRONG!! Of course I hit the expert resources at various forums and FaceBook user groups only to confirm that there aren’t off-the-shelf controller solutions available. It was suggested numerous time to build my own like others had been doing for years using MCU development boards or purpose made CNC controller boards. The only problem was support and documentation. I found tons of generic CNC controller boards from Chinese manufactures that looked great and were really inexpensive. But none of them came with any documentation or support.
CNC Controller Firmware
So if GRBL 1.1 only supports 3 axes, then what supports more? GRBL 2.0? Nope, no such thing. I was expecting that the CNC firmware world would be very advanced and up to date. Turns out it’s NOT! GRBL 1.1h is the newest and it’s from 2019! Yikes. So what do I need then? There’s not much to choose from. I had pretty much settled on grblHAL, which is a fork of grbl with enhanced features and, most importantly, would handle a 4th axis. Then I came across mention of FluidNC. It seemed really good with lots of features. While researching FluidNC I came across purpose made CNC controller hardware designed by the same dev, Bart Dring, that created FluidNC. That seemed like the way to go. But it was still very confusing due to everything being so generic and configurable in order to work with a broad range of use cases and CNC machines. You still have to pick from a variety of stepper motor drivers. Some of which plugged into the CNC controller boards and some were external. Again, what to choose. Not to mention that Bart’s Tindie store was closed with a message he was on vacation and to visit his partner at Elecrow.com. I did my best and was going to order from Tindie but the products are constantly out of stock. So I was going to order from Elecrow but not everything was in stock there either and there were even more choices so I gave up for a while.
PiBot
There was an interesting CNC controller board on Elecrow from PiBot. They have their own web site so I started researching there. They reference the FluidNC WiKi, which in turn references the PiBot as supported hardware. I ended up ordering the PiBot 4.9 PLUS B from the Pibot web site. I also decided to go with external stepper motor drivers that would handle the NEMA23 motors I eventually wanted to upgrade to. After a lot of research I went with TB6600 drivers.
Everything Else!
Now that I finally decided on a controller and firmware, I needed, well, EVERYTHING else! So just what IS everything else? Yep, the Black Hole is sucking me in big time now.

