[drew_spriggs]

Howdy,

Recently offered to help repair/rebuild a CNC3D QB2 that belongs to a community workshop. The guy in charge of it really, really had no idea what he's doing (not that I'm an expert; I've run a couple of big CNC lasers, have a small desktop CNC at home and have been messing with 3D printers for years) and the machine was in pretty bad shape.

Couple of hours of troubleshooting (one of the Y motor couplers was super loose), doing ANY maintenance as nothing had been done in two years, a couple of hours of building a new bench for it (rather than it sitting on a single sheet of 5/8" timber with a single leg on each end held down with two short timber screws) and some figuring out what the hell had been done to the machine and we're ALMOST back up and running properly. Attached a couple of quick photos of where we're at now, as well as some of the parts I've designed/printed for it.

1 - the controller, a Nighthawk v1, only outputs ~9v so the VFD will only spin the motor up to 21.5k. It's not trimmable on the controller and the VFD won't allow any compensation, so unless I build an adjustable external amplifier this is about where we're at.
2 - the bottom spoilboard only has a handful of screws holding it down to the machine rails. In use, the entire spoilboard lifts up 1/16". I've got some new 5/8" MDF on the way that I'm going to make a new base board from, and then another spoilboard with t-track rails sitting on top.
3 - somehow the original dust boot was melted (quite an achievement), so I've been working through the process of designing a new one from scratch. It's currently printed in reinforced PETG, and the magnet attach system works perfectly.
4 - there was a cheap, ****ty vacuum near the CNC that was apparently used by following the head by hand as it cuts....although there's a 4" plumbed dust extraction system right to the machine. I've designed adaptors/a ball valve system that's also 3D printed that is going to attach the two - just waiting for Sikaflex to dry.

Once we're at least at a point where it's working properly, my next project is going to be getting the machine at a point where it's easy enough to teach beginners the basics of machining on it. I've thought about various vacuum beds and simplified workholding, but haven't quite come up with a cheap/easy solution that's idiotproof; unfortunately a real consideration for a machine in a space like this.

Any suggestions for idiotproofing basic machines like this?

[routalot]

The controller issue looks like the biggest obstacle,but given the huge improvements you have made so far,I'm guessing that once they witness the things the machine is capable of there might be enthusiasm for an upgrade there.Its really great that you are taking the time to get the machine running and introducing a new generation of people to the possibilities of CNC machining.

[drew_spriggs]

Made the new base board and found out the machine frame is super, super out of square. Couple of little taps and it's CLOSER, but not perfect.

I've got one of the spoil board pieces on, but I've got some spares so to save time I'm going to flatten it, then use it to cut all the others. At least it's an easy size to make (and under the total size of the work area), so if we need additional ones it's trivial to cut them