Here’s a simple alternative to some of your standard shop made circle cutting jigs. This circle cutting router jig is infinitely adjustable so you can make it to cut any size circle you choose.

Start with a piece of 1/2″ plywood about 2″ wider than your router base, and as long as you. Remember, the longer the base, the larger diameter circle you can cut; but this circle cutting router jig can also become unwieldy to use for smaller circles if you make it too long.

Cut some hardwood blocks for each end, drilling holes to align to the steel rods going through your router’s base and 1/4″ holes for 20 tpi bolts to use as stop screws to prevent the steel bars from sliding. On one of the blocks, also thread a 3/8″ diameter hole through the center for a 16 tpi bolt to use for fine adjustments of your router.

Attach your router with a 1/4″ upcut bit, and slide it to the end away from the adjustment bolt. Complete a plunge cut through the base. This is where you’ll be able to insert a 1/4″ x 1″ dowel to go into a corresponding hole in the center of your workpieces to create the fulcrum for this jig.

Then slide your router out about one inch, and route a slot all the way through the jig base until the router base pushes up against the block by the adjustment screw.

* This post may have affiliate links, which means I may receive commissions if you choose to purchase through links I provide (at no extra cost to you). As an Amazon Associate I earn from qualifying purchases. Thank you for supporting the work I put into this site.