Monday, December 19, 2016

Upgrades, mostly complete





Over the last weekend I've managed to install several new upgrades, centered around a new X-axis. The goal was to be able to run a dovetail bit through oak, and I'm happy to say it can.

X-Axis, front
X-Axis, back
The two 1800mm lengths of MakerSlide for the X-axis have been replaced with a single 80/20 25-5010 extrusion that is 100mm tall and 50mm wide (you can get an idea of big it is by looking at the X-Axis pictures). The V-Wheels for the X-axis ride on black OpenRails that are attached to the 25-5010 extrusion.
To mount the new 25-5010 X-axis I've milled new plates for the X-axis and the Y-axis. The plates are made out of 1/4" aluminum, and are considerably larger than the steel Shapeoko 2 plates I started with. The Y-axis plates sprout three V-Wheels on top instead of two. Since I knew exactly where all of my screws were going to be before I started, I replaced all of the slots in the original Shapeoko 2 plates with simple holes so I wouldn't have to make any adjustments. The holes were also faster to mill than slots.
Y-Axis
I've replaced the 1.8Nm NEMA 23 motor on the X-axis with a 13Nm NEMA 34 motor from omc-stepper online. The new motor required a new, larger pulley, and I upgraded the X-axis belt to a 15mm wide GT-3 belt. The new belt required custom clips milled out of acrylic to hold the belt. The new belt also needed custom 15mm wide idler wheels, which I ordered from Pulley-N-Wheel.
The X-Controller is driving the 13Nm NEMA 34 motor just fine, although the X-Controller can only put out 4 amps and the motor wants 5 amps. I'd rather have motors that can take down more current than the controller can put out than the other way around.
The design works pretty well, but the drag chain mounts remain a work in progress. I'd add a fourth wheel to the X-axis plates if I got a chance to mill them again. The X-Axis plates have holes to mount NEMA-34 motors, but I'll probably need the 4th wheels if I add the weight I'd get from two more NEMA-34 motors. My first attempt at mounting the X-axis ran into a collision between the screws holding the terminal block and the screws holding the OpenRails in place.
The only problem I've ran into so far was that I forgot to fully tighten the set screws for the X-axis, and debugging the backlash caused by the screw moving along the flat portion of the axel took a while.
X-Axis acrylic tabs