I needed a longer bar than John's original to allow the dial indicator to clear the Z-axis mounting plate on the X-axis. I also wanted to secure the router bit and dial indicator, so I split the ends of the bar and added holes for screws to clamp both ends tight. The model is designed for 3mm hardware. The bar has a ¼" hole for the router bit and a 3/8" hole to fit my dial indicator.
I printed in PETG for flexibility in the clamp area, 4 perimeters for added strength, outer perimeters first for dimensional accuracy, 30% infill, no supports.
I have included a .STEP file if you want to modify the model.
The author remixed this model.
Longer
Added hardware to clamp router bit and dial indicator