There are many ways to cut circles in woodworking, but choosing the appropriate procedure is paramount to the quality of cut. This decision is usually dictated by the scale of your work. When dealing with larger pieces, an adjustable trammel is one of the first jigs I grab to make precise radial cuts. The simple, yet adaptable system allows you to bring the tool to the workpiece and makes cutting out large diameter pieces — accurately — a breeze.
On the other hand, smaller parts with tight radii warrant a similar strategy, however, often propose challenges due to the scale of the tool being used in relation to the diminutive size of the piece being cut.
A solution to this is a two-step process which makes the task of cutting these small parts both safe and exact. To do so, a band saw was used in conjunction with a shop-made router jig that makes both the exterior as well as interior radial cuts needed to complete the part. Follow along as we discuss a couple of options (both shop-made and purchased) that are up for the task.
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| All that’s needed to make “perfect” circles is a sheet of plywood, a piece of rod, and a router bit. Two holes were drilled. One is for the router bit and the other is for the bit height adjustment. Here, we used a 1⁄4" piece of brass rod for the pivot and a 1⁄4" upcut bit to make our cuts. |
The nice thing about shop-made jigs is that they can be created using materials that are readily available and rendered too small for other projects. We all know there is a stash of scrap in every shop that has made the empty promise of becoming a hypothetical project some day. So take this opportunity to be the person you lie to yourself about being and use what ‘s been gathering dust, and turn it into something functional.
If, on the other hand you happen to be someone who prefers the confidence of a store-bought option, there is a jig available that makes quick work of all things circles — small to medium-sized in diameter.
SHOP-MADE JIG FOR THE JOB
To create the circle-cutting jig used for the music stand, all that is required is a piece of 3⁄4" plywood and 1⁄4" dia. rod. I started by cutting the plywood to the length of my router table top so that I could easily and securely clamp on both sides.
Then, two 1 3⁄4"-dia. holes were drilled to allow for the router bit to pass through, as well as for the height adjustment wheel to be accessed. Between those two holes is a 1⁄4" hole that acts as the pivot point for the two brackets. Note: the two holes drilled for the router bit and adjustment wheel will be contingent on the setup you have, so take note of their locations and drill them accordingly.
Once you have established the hole locations, drill the pivot hole 1 1⁄2" from the center of the router bit hole. This will provide you with enough room to move the jig to sight the two separate cuts. Place the pin and affix the jig to your table top.
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| Remove the waste using the band saw. This will help cut down on the amount of passes performed at the router. | Pilot holes were drilled at both ends of the pivot slot. This acts as a locator window that assists with jig setup. |
In step 1, you’ll notice a printed pattern was used. This saves time and ensures accuracy with your cuts. Continue by placing the blank onto the pivot pin and adjust your jig to locate the two pilot holes seen in Step 2.
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| Continue to raise the bit about an 1⁄8" and make several passes until the slot is exposed. This is not only good practice, but also ensures a smooth and accurate cut. | Clean up the band saw marks by rotating the blank into the cutting rotation of the bit. Move slowly to avoid tearout against any exposed end-grain. |
Once you have sighted the first hole, start with a bit height of about 1⁄8" and rotate your piece until you reach the corresponding pilot hole (Step 3). Continue by raising the bit until you have cleared through the blank. Repeat this for the second bracket.
To complete the brackets, readjust the jig to make slight contact with the profile’s exterior. Then make a finishing pass using the refrence on the pattern as your guide (Step 4).
JASPER CIRCLE CUTTING JIG
Another great option for cutting small circles that is commercially available is the Jasper 240 Pro circle-cutting jig seen on the bottom of the previous page. This is an inexpensive ($39.95) remedy if you are someone who cuts small parts frequently.
It has the ability to cut 256 different-sized precision circles ranging from 1" to 18 3⁄16" in diameter. It’s made from hardened acrylic and is compatible with over 47 dif-ferent plunge router bases. If consistent and precise circles are part of your woodworking regimen, a more permanent jig like this one is more than worth adding to your arsenal of tools. Whichever option you choose, both will have you cutting small circles like a pro with minimum setup.
| USING A JASPER CIRCLE-CUTTING GUIDE |
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| Mount the Jig. Using the included locating pin and calibrating disk, mount the jig on the router. |
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| Locate the Pivot Pin. Drill a 1⁄8"-dia. hole in the workpiece. Then insert the pin in the proper hole in the jig. |
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| Rout the Circle. Position the pin in the centered hole, plunge the router, and complete the circle. |
