ShapeOko Upgrade

I've recently had the time to make a number of modifications to my ShapeOko CNC router. While the original kit worked well on softer materials, it quickly became frustrating to deal with aluminum milling. To minimize flex across the X axis and the limited torque of the Dremel spindle, the ShapeOko had to run at painfully slow feed rates and small depth increments. This meant that even small parts required hours of time standing at the machine, manually spraying lubricant and monitoring progress. Even with those conditions, the tolerances were not as accurate as I would have liked.

I started out by designing and welding a "cage" to permanently house the ShapeOko in. The thinking was to cover it in panels of clear acrylic to prevent the clouds of sawdust that came with routing wood. It also allows the baseplate to be removable and provides space to put a drip tray below the mill if I decide to use lubricant when cutting metal.

It is pretty obvious that this frame is not based on the standard ShapeOko dimensions. The size reflects the new expansions made to the Y-axis to increase it to 1000 mm.  I chose to paint it blue just to create some bright contrast against the red ShapeOko. The extended bar visible on the  top of the frame in the picture is not a mistake, but instead where I intended to mount a new electronics box.

Instead of sitting on top of the workbench waiting to be shorted out by metal shavings, the Arduino+Grbl Shield and 24 volt power supply now have a home inside a new box. The connections run to four male connectors mounted on the box. The mystery fourth connector is for the new stepper I am installing across the X-axis to run a duel motor setup. This will reduce wobble that previously came with having an unpowered side of the Y axis.

More clearly visible here are the two fans and buttons that were installed. The power switch runs between the power supply and the Grbl board, it does not turn the power supply on or off. Also included are two new 12 volt fans run in series to help provide some extra cooling to the stepper drivers. Finally, the essential reset switch was also brought out to the front.

Here is the frame with the box mounted. It turns out I overestimated the strength of the ABS RadioShack project box, and assumed that two bolts through the top would be sufficient to hold it on. With the weight of the power supply, however, the entire box flexed to a point where it wouldn't even close. The solution was a piece of square steel tubing added along the inside top of the box to help it retain its shape. The steppers were wired to the box with 4 conductor wire from McMaster-Carr and female 4 pin connectors.

Visible here is another upgrade I made to improve rigidity. The secondary piece of MakerSlide across the X-axis probably isn't strictly necessary, but I figured it couldn't hurt.

The final change was the switch from a Dremel tool to the Dewalt DW660. The router seems to have some decent power, and I have supplemented it with a variable speed control and laser tachometer so that I can actually start to record some cutting data. All parts of the new ShapeOko setup seem to be working well at this point, and I will probably update with more details after I get the chance to make a few test cuts.