Boxford 260 VMC rebuild

[mike-f]

Well, folks, It's there—just a few odds and sods left to sort: reassembly, wiring, setup, cobbling together a 4th axis, and the small matter of squeezing this beast into my gloriously cluttered workshop. Wish me luck!
For the controller and electronics, I stuck with tried and tested stuff I have used before. I plumped for the ever-reliable CNC Drive UC300ETH motion controller—used the USB version before and loved it. It’s got bags of inputs and outputs, plus those handy dual analogue inputs for SRO and FRO. For stepper drives, I went with ANGEEK DM556s. At a wallet-busting £8.99 each (including next-day delivery, no less!), they’re an absolute steal. I’ve used these drives before, and they’ve never let me down, so why splash out on pricier kit?
The spindle drive was a bit of a saga. I had a nice Parker Compax3 with an AC servo motor just waiting to be used. I was aiming for spindle reversal and maybe rigid tapping down the line. Sounds simple, right? Not quite. The drive only plays nice with a limited set of inputs: ±10V, open-ended 24V step and direction, or 5V differential. I faffed about for ages trying to get the first two methods to work, but clean input signals were as elusive as a sunny bank holiday. In desperation, I tried driving the 5V differential inputs with 5v open-ended drive signals, despite the manufacturer insisting it was impossible. Lo and behold, it worked! Take that, naysayers. To bridge the gap between the UC300ETH and the drive, I used a couple of dirt-cheap 5-axis breakout boards off eBay.
My one cock-up? Mounting all the control and breakout components behind the control panel. Seemed like a great idea at the time, but it’s now tighter than a sardine tin back there. Lesson learned. On the plus side, I’ve kept the high-voltage, noisy stuff tucked away in the rear of the cabinet, with the spindle drive well clear of the stepper drives to avoid any electrical tantrums.
I just have to get all the heavy bits into the cabinet without serious injury!
A few pictures of the work below.

[Lee Roberts]

Looking really good Mike, I'm going to take a punt and say you've done similar work before

[grain_r]

That looks a great build, Did you spray the Cabinet with a HVLP gun or cans ?.Im just prepping a Lathe I brought a while ago and about to start painting I have been torn with spraying for a nice job or brush for a thicker and quicker job.

[mike-f]

Looking really good Mike, I'm going to take a punt and say you've done similar work before

Thanks Lee, I have had a bit of experience but never had to do so much to a machine. The last was a Boxford 240 CNC lathe but it was in pretty good condition so just needed all the electrics and spindle drive etc.

[mike-f]

That looks a great build, Did you spray the Cabinet with a HVLP gun or cans ?.Im just prepping a Lathe I brought a while ago and about to start painting I have been torn with spraying for a nice job or brush for a thicker and quicker job.

I used Rust-oleum hard hat top coat, it is fantastic paint. I was originally going to get the cabinet shot blasted and powered coated, but quotes seemed a bit crazy so rattle cans it was. The problem with Boxfords is that the original paint is rubbish so moisture gets underneath and you really need to strip it all off or not bother.

[mike-f]

Due to the cramped nature of my workshop, I decided to assemble the machine in situ. After manhandling the lighter VMC 190 out the door, I brought in the main cabinet body and rear section and got them assembled. Next, I installed the rear electrical panel, servo drive, and most of the wiring, along with the connector for the 4th axis. At this stage, the machine was still light enough to rotate on its stand, making it easy to work on from the front or back.
Once I had the stepper motors moving and the spindle motor running, it was time to fit the heavy bits. The Y-axis base bolts to the column with a bunch of M6 cap screws. Interestingly, when I disassembled the machine, about half of these weren’t even hand-tight! I made sure to tighten them properly this time and used thread lock to ensure they’d never come loose again.
Unfortunately, the resulting assembly was way too heavy for me to lift into place without risking scratches to the paint. What I did next probably shouldn’t be tried at home. I built a bridge using an 8mm-thick high-tensile aluminium plate from the bench to the machine cabinet—100% totally safe, of course! The column assembly was then carefully slid across this makeshift bridge and into place within the cabinet. It was pretty much open road from here, with the column assembly bolted into place and sealed with clear silicone, the other parts could be added and tested. Pictures hopefully below: