How to Cut Circles - 4 Methods
Intro: How to Cut Circles - 4 Methods
In this tutorial, I’ll show you 4 ways to cut circles in wood, using DIY homemade circle cutting jigs.
Below, I’ve included a summary of how to make each circle cutting jig, whether it be with a router, a bandsaw, a table saw, or even a jigsaw. For a closer look at each method, be sure to check out the YouTube video.
STEP 1: Router Circle Jig
The most common way of cutting circles in wood is using a plunge router with a circle cutting jig. Now, you can buy a circle jig to fit your router, like this one, or you can make one yourself out of 1/4 inch plywood. I used my bandsaw to shape it, but this step is optional.
Remove the base plate from your router and use it to trace the screw holes on one end of you strip of plywood.
Then attach the router to the plywood making sure to countersink the screw heads.
Plunge the bit through the plywood jig, then remove the jig from the router and make the hole bigger.
STEP 2: Using the Router Jig
To use the jig, make a small pilot hole in the jig, measuring from the edge of your router’s bit. For an 18 inch diameter circle for example, make a pilot hole at 9 inches from the bit.
Find the center of your wood blank and drill a pilot hole, then mount the jig using a finish nail.
With an upspiral bit mounted in the router, plunge the router 1/8th of an inch and guide the router around in a clockwise direction until you’ve made on full revolution.
Adjust the bit to plunge 1/8th deeper and make another revolution at this depth. Continue until you make it all the way through the wood and you’re left with a perfect circle.
STEP 3: Router Circle Jig + Jigsaw + Flush Trim Bit
This method starts out the same as the previous using a plunge router and a circle cutting jig. Using the upsiral bit to make 2-3 revolutions, then remove the circle jig and grab your jigsaw.
Using the jigsaw free-hand, cut out the circle using the groove as a guide. Avoid getting too close to the inside edge of the groove, so that when you’re done, you’ll be left with a lip all round the circle.
Grab your router and install a flush trim bit with a bearing. Plunge the router and line up the bearing with the clean lip previously left by the router.
Going in a counter-clockwise direction, progressively shave off the excess wood until the bearing contacts the lip. Go all the way around the circle until you are left with a perfect circle.
STEP 4: Bandsaw Circle Jig
If you have a bandsaw, I highly recommend this method. Cut a runner out of hardwood to fit the bandsaw’s miter slot, and a piece of 3/4 inch plywood. Attach the runner underneath the plywood so that the plywood overhangs the bandsaw’s table on the right.
Mount the sled to the bandsaw and cut the kerf, stopping about half way through.
Then mount some stops from underneath up against the front edge of the table.
Trace a line perpendicular to the front tip of the kerf line, then drill a pilot hole on the line to match the radius of the circle you want to make. Use a finish nail with the head cut off as a pivot pin.
STEP 5: Using the Bandsaw Circle Jig
To use the jig, find the center of your wood blank and make a small pilot hole, then mount the blank to the pivot pin on jig.
Using a 1/4 inch bandsaw blade, slide the sled forward straight, cutting into the blank, until the stops hit the table and you can’t push the jig forward any further.
At this point, simply rotate the blank clockwise and cut the circle.
STEP 6: Table Saw Circle Jig
The last method made me a bit nervous at first, but I just had to give it a try. Cutting circles with a table saw? Yes, it is possible.
Mount a runner to a piece of 3/4 inch plywood, then run the sled through the blade to trim off the excess and create a zero clearance edge.
Trace a line across the sled, perpendicular to the blade, about half way front to back. On this line, drill a pilot then drill hole on the line to match the radius of the circle you want to make. Use a finish nail with the head cut off as a pivot pin.
STEP 7: Using the Table Saw Circle Jig
To use the jig, find the center of your wood blank and make a small pilot hole, then mount the blank to the pivot pin on the jig.
Start by slide the jig back and forth through the blade to cut off the 4 corners of the square blank.
Continue to cut off the 8 remaining tips of the blank. Then again to cut off all remining protrusions until your blank is as close to a circle as you can make it.
Line up the line on your jig with the front tip of you saw blade, then use a magswitch or stop to lock the jig in the position.
Using push pads to protect your hands, rotate the blank clockwise into the blade in order to shave and sculpt it into a perfect circle.
STEP 8: Choose Your Method!
My favorite method was definitely the bandsaw, while my least favorite was the Table saw.
The router option is messy, but there's no limit to how big you can make your circle, like for a tabletop. I prefer to stick with the upspiral bit all the way through.
If you haven't already, watch the YouTube video for more details, and if you like what you see, subscribe to my YouTube channel.
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42 Comments
MechaNickW 2 years ago
YzYnGy 2 years ago
chefspenser 3 years ago
telesphorelalancette 3 years ago
rblume73 3 years ago
cheap132 3 years ago
bpark1000 3 years ago
Setting the blade high also gives truer cut when you get to the final "spin" pass.
Your comment about bandsaw being limited in radius is true only to the extent you don't have room off to the side of the table. The clearance of the saw only limits the amount you can cut off IN ONE PASS. You can precut the corners off until you are less then that. You must set the pin carefully, accounting for the "lead" or cutting direction, or the blade will be pulled to the side, and produce a spiral and then jam. You can adjust for this by moving the sled forward/backward and making test cuts. Use a blade with a high tooth set. Avoid "thin kerf" blades. Set guides close and keep blade tension high.
Another method to make circle is to first make template from scrap (using your's or other methods), fastening this to the work, and using router with follow-bearing against the template.
dwieland 3 years ago
bpark1000 3 years ago
When wood binds against the blade, it is pushed back. With usual table saw arrangement (wood getting pushed directly in, fence parallel to the blade), backward motion tends to relieve the bind, and there is no tendency for the work to rotate because the binding force is in line with the pushing force. But in your setup, the wood piece is pivoted about the center point of the circle, which is laterally offset from the blade, and connected to a massive sled. If the work binds the blade suddenly, the inertia of the sled will resist moving back. The offset force will cause the work to rotate about that pivot, toward the blade, causing the bind to get tighter, contacting the blade in the back. The only thing preventing this is the friction between the work and sled and your holding blocks, which is no match for the saw. The work will lift, and it and the sled will be shot back! Once the work is roughed out, the danger of binding is little as the blade is not embedded in the work. For all of the cuts, setting the blade as high as possible reduces the amount of pushback, and keeping the cuts short so the back side of the (up-moving) blade is not contacted (geometry more like the bandsaw setup). Having a guard in place "protects" the high-set blade and prevents the work from lifting. The high setting also makes the sled position easier to determine, and the final spin-cut truer.
I hope you have Saw Stop on that saw!
dwieland 3 years ago
4DIYers 3 years ago
SuperMagnetMan 3 years ago
RikkiePi4 3 years ago
For small circles I sometimes use hole saws lol. But you must have the right size of course, secondly there will be a drill hole left in the center.
SuperMagnetMan 3 years ago
john buschiazzo 3 years ago
ameerdb 3 years ago
Lee73 3 years ago
Ironworxx1 3 years ago
Thanks,
Mike @ Ironworxx Guitars
JavierL90 3 years ago
Whyfrog 3 years ago
Your methods are well explained and would make creating circles much easier. But do you have a method of cutting a circle in a piece of wood where the circle is NOT the object to be used.
My daughter was asking me minutes before I saw your Instructables on creating circles easily with power tools.
She wants to build a dog food bowl stand and wanted to know the best way to remove the wood so the bowls will be inserted in the shelf.