4 Ways to Cut Circles in Wood // DIY Circle Cutting Jigs

In this video, I'll show you four different ways to cut circles out of wood using various tools. I'll show you what works for cutting really big circles and how to cut tiny ones too. So the only method I've actually ever used to cut circles is my router, but today I'm going to figure out how to make some really simple jigs using different tools around the shop. Now be sure to stick around until the end where I go through my favorite and not so favorite methods and go through a few of the pros and cons of each. The first method is using a plunge router and a circle cutting jig. Now you can buy a jig, but I'm going to make one out of a scrap piece of quarter-inch plywood. I could leave it like this, but I'm going to trace out a shape to make my jig look a little more professional. With that done, I used my bandsaw to cut out the shape. After that, I ran the edges on my sander just to smooth out all the edges and avoid any potential splinters. The good thing about making your own circle jig is that you can be sure it'll fit with your router. Just remove the base and use to trace out the screw holes. Then drill the screw holes and make sure to countersink them so that when you attach the jig to the router, the screw heads will sit flush below the surface. I plunged my bit through the jig, then removed it and made the hole bigger using a 1-inch forstner bit. Okay, so if I want to make, say, an 18-inch diameter circle, I'll make a mark at 9 inches, measuring from the bit, and make a small pilot hole in the jig. Here I'm getting set up with my bench cookies to start routing out my circle, but first I took a minute to install a cord reel that I picked up at Princess Auto. In my small shop, I'm constantly tripping over extension cords, so this should help keep my cords out of the way. So with that, I could plug in my router and get back to making circles. I found the center of my blank and made a small pilot hole just big enough to hold a finish nail that I hammered into place, then checked that my jig moved smoothly all the way around. I set my plunge depth to 1 eighth of an inch and plunged the bit, then went around in a In case you're wondering, I'm using an up-spiral bit from CMT Orange Tools, the sponsor of today's video. After the first pass, I lowered my bit another eighth of an inch and made a second pass at this depth, then repeated, going progressively deeper on each pass until I finally made it all the way through and was left with a perfect circle. Now this method, as with each of the methods, will leave a small pinhole in the middle of the circle, but this will usually go on the bottom of a table or something and be hidden. Alright, so not bad at all, but this piece was relatively thin and, although large, not that large. So what happens when you have a really big piece, like a tabletop, that's thick and maybe out of hardwood? Well, that's where the second method comes in that combines both a router and a jigsaw. Just as before, I'll first start by using a router circle cutting jig. I made another pilot hole in my jig to make a larger circle and found the center of my piece of wood, then secured the jig with a small nail. Just as before, I started with a shallow depth of one eighth of an inch, plunged my router, and went around clockwise. I went a little deeper on the next pass and made about three revolutions in total, then stopped. At this point, I removed the jig and grabbed my jigsaw. For the next step, I'm going to use a CMT fine cutting blade. You'll find a link for all the tools I used in this video in the description down below. The idea is to use a jigsaw to cut away the excess material. I'm using the groove left by the router as a guide. I want to cut close to the inside edge of the circle, as close as possible, without actually touching it, so that when I'm done, I'll be left with a lip all the way around that I'll shave off in the next step. To do this, I'll flip over the circle so that the lip is on the bottom. To shave off the excess wood, I'll use this CMT flush trim bit. I lined up the bearing with the bottom lip, which will serve as my guide, and with that setting locked in, I went around the circle, this time making sure to go counterclockwise. I realized making this cut in one pass was a bit ambitious according to the sound my router was making, so I made progressive shallow passes, always right to left, until the bearing bottomed out against the wood. Eventually, after several passes, I was left with a perfect circle and a huge mess. Alright, so those were the two circle cutting jig options. Personally, I prefer the first option, using just the up-spiral bit with the circle jig, versus using a combination with the jigsaw and then the router again. I just find it takes less time to just stick with the jig, and yeah, it takes a lot of time to go around and around and make it all the way through, but still, I think it saves time in the long run. Plus, it made much less of a mess than using the flush trim bit at the end there, so I would stick with the first option. Next up, let's take a look at the bandsaw and make a circle cutting jig for that one. The next method I'm going to try is the bandsaw circle cutting jig. For this, you'll want to use a thin quarter inch blade, which will make it easier to cut small circles. I want the jig to overhang, so I'll make it about 18 inches this way and about 20 inches this way. I cut the base out of 3 quarter inch plywood, then grabbed a scrap piece of hardwood to cut a runner to fit the miter slot. It should be snug, with no side-to-side play, and sit just below the table. With that, I roughly positioned the base where I wanted it, skewed to the outside, and then roughly marked the runner's position. I applied some glue, then positioned the runner on the markings, and used a square to position the runner while I secured it with a few brad nails. With the runner secured, I installed the jig on the bandsaw and cut the kerf, stopping roughly halfway through. At this point, I used a couple of clamps to lock the jig in place temporarily. You'll notice the jig overhangs the table at the front, and this is important so that you can secure a stop. Make sure the stop you're using is thin enough so that it won't hit any obstacles. I used a few dabs of super glue to secure it under the sled, up against the bandsaw. I had to use two short pieces due to some obstacles, so I added a second stop on the other side, before taking it back to my workbench and securing the stops with a few brad nails. At this point I could trim the runner to size, then grab a square that I'll use to trace a line perpendicular to my kerf line, starting right from the tip of the kerf line. I'll use this line as a reference to measure and make holes for a pin that will secure my workpiece and act as a pivot point. For my pin, I'm using a simple finish nail with the head cut off. I found the center of my blank and made a small pilot hole for the pin, then mounted it to the jig. Alright, we're ready to cut some circles. After mounting the jig, I fired up the bandsaw and cut straight into the workpiece until I hit the stops and the sled couldn't move any further. I could then rotate the workpiece clockwise, and I was surprised by how easy it was to cut a circle this way. I think I found a new favorite method to cut circles. In a few seconds, I had a perfect circle cut out. The one drawback I did notice is that the blade leaves marks around the edges, so a little more sanding would be required using this method. I was curious to see if I could cut a really small circle using this jig, and I wasn't disappointed. Alright, so that's a wrap on the bandsaw method, and if you have a bandsaw, I highly recommend using this method. Not only is the jig super fast and easy to set up, but cutting out circles takes no time at all, and it's especially effective when cutting out really small circles like this one. Next up, I'm not too sure about this method, but I'm going to try to cut circles using my table saw. Let's go! The next and final method is a table saw circle cutting jig. For this, you'll need a piece of 3 quarter inch ply and a strip of hardwood for the runner. After cutting the runner to size, I used a few pennies to raise it up slightly. I want to position the base so that it overhangs the blade just slightly. I applied a few dabs of super glue, then held it down 30 seconds while it bonded. I could then remove the sled and drill a few holes using a countersink bit and secure the runners using some number 6 screws, making sure to sink the heads below the surface. I trimmed the runner to size and then tested out the sled to make sure it was sliding smoothly. Before going any further, I'm going to swap out my old blade that's getting pretty dull and replace it with a 50 tooth combination blade. With that done, I could trim off the edge of the sled and create that zero clearance edge, getting a nice clean cut. About halfway front to back, I made a line through the sled that will again be my guide for making pilot holes and putting a pivot pin into the sled. After finding the center of my board, I made a pilot hole and mounted it to the sled. Okay, the idea from what I've seen is to start by cutting off the four corners of the square. Next, I'm going to cut off the eight tips, progressively making the shape more circular. Okay, now I'm going to keep shaving off the remaining tips in order to make this as close to a circle as possible. With that done, I grabbed my mag switch and positioned it so that the line on the sled is right at the front tip of the blade's teeth. With the sled pushed up against the stop, the idea is to rotate the circle clockwise into the blade. That being said, I found getting the placement of the sled just right took a lot of trial and error in order to find the sweet spot that would create a perfect circle. I repositioned the stop and tried again a few times, but as you can see here, I'm actually getting burn marks, which is not what I want. Ultimately, I found that this position worked best for me, but it's definitely worth experimenting with different positions. Once you find the sweet spot, you can actually get a really decent clean cut circle using a table saw. Who would have thought? So my least favorite method had to be the table saw. Maybe there's just something about using a table saw to cut circles that makes me uncomfortable, but besides that, I found it really hard to find that perfect sweet spot where the blade will make that perfect circle. So, not my favorite method overall. Now, my favorite method had to be the bandsaw. Not only is it quick to set up this jig, but cutting out circles is super fast. And on the plus side, you can make these really tiny circles no problem at all. On the downside, there are some limitations to cutting circles on the bandsaw, one being the size of the circle that you can actually cut out. Other than that, it does leave some marks on the outside of the circle that you'll have to sand away. But besides that, this is a pretty great method. Now, the router option is a really great option. Sure, it makes a mess, but there's really no limit to the size that you can make this jig and you can cut out really huge tabletops using the router. I do recommend sticking with just the upspiral bit rather than using the jigsaw and the flush cut bit. It just seems faster overall and less steps to actually cutting out the circle. So just stick with that bit and you'll have a perfect circle in no time. All right, well, that's a wrap on this video. Until next time, thanks for watching. See you soon.