In this article I’m going to show you how to use an inexpensive jig to mill circles along with a homemade base plate to be able to attach the router more easily.
In this other article you can see how I’ve modified this affordable circle jig to convert it into a professional tool that will allow you to get more out of your router.
This is the 3D design included in the plans you can download for free in my website. I’ll leave a link on the bottom below. They also include a printable template that you can stick on the board to make the job easier.
Quick Install Base Plans
It’s a circle jig with an incremental system made out of aluminum. It only costs around 25 euros, so I don’t think it’s worth it to build it at home. It’s a little hard to make an incremental system that works accurately.
This jig comes with an optional fixed base router, but I don’t recommend buying it at all. Instead, we could use the fixed aluminum base that comes with these kinds of routers, but this base has the downside that it doesn’t have a plunge system which, in my opinion, is indispensable to use with these kinds of router jigs.
Therefore, I decided to modify and improve this jig so that we can use it with the plunge base that usually comes with these routers.
Besides allowing us to start the milling jobs more easily, this kind of plunge base has an accurate stop and accessories so that you can connect it to a vacuum. The only drawback is that it’s a little heavier than the fixed base.
In order to use it with this jig, I have to raise it a little, about 6mm. I planned to make a system to attach it my router to the jig in a quick and convenient way. I waste quite a bit of time every time I have to attach my router to a jig, which led me to develop a new and innovative coupling system.
I’m going to use the same lock system used in these bases to attach the parallel guide.
Attaching the router to the DIY base is this simple and quick. First we have to screw the base to the jig using the holes that come by default.
After that, we only have to insert the base into the steel pipes of the jig and tighten the three knobs that come with the plunge base to lock the parallel guide. It’s that quick. I think this is a perfect system to add to any router jig you have at home
I’m going to run some tests with the board I had already used to try my other DIY incremental circle jig for use with a router table and band saw.
First of all, we have to drill a hole in the board to insert the steel rod that acts as rotation axis, and then position the jig. I’m going to set the depth for the router. It seems the jig works wonderfully. The only problem is that the power cord and the vacuum tube get a little tangled when milling. I have to come up with a system to hang them from the ceiling.cho.
This is the circle with the smallest diameter I can make with this jig, around 40 mm. I’m going to use the incremental system to move the milling by about 2 mm.
I’m going to mill again to check the maximum diameter with this other jig, about 150 mm.
In order to cut at wider diameters, I modified another cheap jig, that I have to fasten to the first one with bolts. I had to cut it down a little, but this will allow me to continue using the first jig’s incremental system.
Thanks to this modification, I can mill circles from 530 mm to 1060 mm in diameter. Between the capacity of both jigs there are diameters I can’t cut. I’m trying to come up with ways to solve this.
The incremental jig comes with a small parallel guide that has two drawbacks. It has a little play, and besides, it doesn’t have an incremental system. I’ve managed to come up with a single solution to solve both problems at once.
I made a new wooden guide in which I can insert the steel rod that acts as a rotation axis; this way I can use the incremental system, and by having two locking points, the issue with the play is completely gone. With this improvement, I can mill more accurately.
I can also use the rotary tool plunge base as before. It will be a perfect combination for small milling projects that require a great deal of accuracy.
