Trim Router Circle Base, Milwaukee M18

I made this so I would have an easy way of cutting various size circles for speakers and other projects. I've been testing it for a year now and it works great, no slipping when tightened and makes very precise circles from under 2" to 12" with included sliders. Sliders can be screwed onto a longer piece of wood to make any size circle.

Short slider tucks in flush with router base allowing you to keep this base installed all the time, the longer slider can be printed for larger circles.

Materials required, any filament will work, I used PETG for this one and PLA for the prototype (not pictured) it also requires a 10-24 bolt 1" long with matching nut for the tightening mechanism. Also uses a small nail as the center of the circle to rotate around, I used a ring shank nail.

Printed using .15 layer height with 40% triangle infill and with supports turned on for base. These settings have proved durable over the past year, there is slight flex but it does not effect the function.

Instructions: Mark center of circle and drill hole same size as pin. Adjust slider to desired size radius and insert pin into correct hole for desired size. Place router on piece with the pin in the hole drilled in the first step. Turn on router and lower into piece using the depth adjuster (router can move during this step so take care). Rotate router around center until circle is complete, lower depth and cut in stages until you reach all the way through. The depth of each pass depends on material being cut and speed of movement and router bit.

It helps to do some practice test runs first before using this on a finished project. Good luck and enjoy, let me know if there are any problems or improvements I can make.