[John Smith_]

do you have a bandsaw or jig saw ?
with a plexi faceplate (or any flat wood) on the router, you can make them consitently the same size.

 

[John Smith_]

I always advocate to make "shop tools" ourselves vs buying something from the store.
Once you make your own, you'll find it very useful for other projects.
Keep us in the loop - Please share your project with us.
Examples of how to make your own circle cutting jigs

 

[John Smith_]

Very nicely done, young man - Nicely done indeed.
Thank you for sharing your project with us.