TOOLS How to: Koil Kutter with a Dremel

Important update

Dave Arens has has handed his Koil Kutter production and selling baton to Kevin and Danielle of Potter USA. Kevin made some improvements including replacing the PVC guild shield with a metal one and adding another groove to the coil holder for smaller coils. Click here to straight to the Koil Kutter product page.

I will update this page to show case the updated Koil Kutter sometime soon. But the basic process shown below for cutting coils is still the same.

Before buying this tool, I tried cutting coils with side cutters, aviator snips and a jeweler's saw. Either the process rendered lousy looking jump rings or the process was very slow. The jeweler's saw makes jump rings where both ends are nice and straight, but I could only cut cut a few rings in 10-15 minutes. It was ghastly slow and tedious.

The Koil Kutter is suh-weet for easily making lots of jump rings. Forget the side cutters, aviation snips and jeweler's saw - get a power tool like this to cut your coils to make your own jumps rings of any inner diameter and gauge your heart desires. Once you set things up, it literally takes a few seconds to cut across an entire coil, making dozens of beautifully cut jump rings. Why use this kind of tool?

If you'd like to obtain a Koil Kutter, visit the Potter USA site.

Basically, these types of tools, the Koil Kutter and the Jump Ringer, have specially designed coil holders with slots for the circular blade to go just deep enough to across one side of the coil. Once the coil is cut, you have a nice pile of jump rings. Good for cutting the softer metals (copper, silver, brass, gold).

From what I could gather online, the Koil Kutter is more cost effective for small scale (hobby) production and you can use a Dremel, Proxxon or Foredom flexshaft.The Jump Ringer costs more, needs a more powerful power source than a Dremel, has a few more options and even a system for high production. Google for more information about the differences between the two cutting systems.

This tute covers how I use the Dremel rotary tool version of the Koil Kutter. This tute is not a replacement for the Koil Kutter instructions . This tute is only a visual supplement. And I'm honored to state Dave provided editorial inputs to this tutorial.


The Koil Kutter kit:

  • coil holder base/block & slotted top
  • guide/shield
  • cutter arbor

Since it in important to have the coil holder block arranged in the right direction, I wrote a few helpful labels on mine using a permanent marker.

"Front" and "Back" seemed to be a good start. The coil block slotted top's stop bump should be on the left. And when ready to cut the coil, you will need to slide the cutter from right to left.

Initially I didn't pay much attention to what was on which side, which way the cutter teeth pointed nor which way I slid the cutting head across the coil.

Jeez, what a mistake that was.


Verify that the teeth on the blade are pointing in the correct direction. Looking from top to bottom, the teeth blades should point counter clockwise.

This is also a very important operational rule, so pull out the magnifying glass if need be, but please get this right.


The collet nut, collet and housing cap or chuck need to be removed. Dremel rotary tools have these parts attached to the motor shaft.

You need to push in the shaft lock button so you can unscrew and remove the collet nut and collet. Then unscrew the housing cap.

Keep this little collection of pieces together. I usually put them in a small reclosable plastic bag.


After the housing cap has been removed, screw on the guide/shield.

The "window" in the side of the guide/shield is just big enough to fit on the coil holder and make sure the blade fits into the coil holder slot.

When you see the entire cutter thing in operation, you'll appreciate the design of the guide/shield. If you've tried cutting a coil without a guide/shield, you're really appreciate this design. ;-)


Push in the shaft lock button and screw in the cutter arbor. Tighten with the little open end wrench that came with the Dremel.

Hint: I was usually hunting for that blasted wrench until I tied a long cotton cord to it. Now, it's easier to find the little wrench because I just look for the more obvious long string.


It's the counter clockwise teeth thing again!

When looking down into the guide/shield, make sure, again, that the teeth are pointing in the right direction - counter clockwise.

Worth repeating - This is very important operational rule, so pull out the magnifying glass if need be, but please get this right.

The consequences of not doing things right include (if you're lucky) but are not limited to a strange bad noise when cutting, a circular blade with missing teeth and a messed up coil. You could even mess up your Dremel or send bits of metal flying. You could even cut parts you didn't want cut. Bad to painful situations.

Since these jeweler's blades are special, not readily available and not that cheap, it's easier to follow directions carefully to keep the blade intact as long as possible.


Details of the coil holder. The groove in the coil holder is where the coil rests. The groove is just wide enough to prevent the coil from rolling.

The top has the slot, wide enough for the circular blade.


A different view of the coil holder and it's slotted top. As mentioned earlier, you might want to write a couple/few labels on your holder to help make sure you do this coil cutting correctly.


According to the Koil Kutter instructions, the coil can be up to 3.75" long, 7/8th inch outside diameter and gauge wire 10 - 30.

I prefer to keep the length at 3.5", no longer. I've found it also helps if the coil is as tight as possible. Gaps not welcome.


Place the coil in the coil holder, right over the groove. Apply a light coating of lubricant across the top of the coil.

Since I tumble the newly cut rings in water with a bit of soap, I prefer to use dish detergent for the lubricant. It's easier to rinse off than cutting oil.

Note: If the rings are going to be tumbled, place a wire through the coil and twist the ends together before putting it in the coil holder. This will help you avoid the tedious task of separating dozens to hundreds of jump rings from hundreds of tumbling shot pieces.


Place the slotted top over the coil, with the stop on the left side. Tighten the screws until they just touch the top plate. With a small rod, toothpick or popsicle stick. push the coil until it hits the stop.

Boni Pienups offers this nifty suggestion to reduce slotted top's tendency to wobble.


Time to cut the coil.

Since cutting the coil produces lots of fine metal dust, I prefer to cut outside. If I cut coils inside, I use a work surface with a backsplash and drape the surface for easy cleanup..

  • Safety goggles on
  • Dremel off
  • Place the coil holder on a level surface
  • Place the guide/shield on the coil holder - the far right side. Make sure the guide/shield rests squarely and evenly on the coil holder. The guide makes sure the blade stays in the slot.
    • see the 2nd photo in this row. notice how the blade sets in the slot and the guide hugs the coil holder block.
  • Dremel on - highest speed
  • While making sure the guide/shield stays in contact with the coil holder, slide the cutter across the coil holder from right to left in a smooth steady motion
  • Dave's instructs "Dremel off" before lifting the cutter off the coil holder. It's a safety step, but not a functional requirement. I've found I usually lift the cutter up then turn it off. It's probably a dumb thing to do, but there it is. I be bad. You should do as Dave instructs. He's the expert. ;-)



Unscrew the right screw and swing the top away. There will be a pile of freshly cut jump rings and a bit of metal dust.

Put the rings in a colander and rinse off the metal dust. Rinse off the coil holder, too. Dry before reusing.

The rings may be a bit rough, so I like to tumble the new rings in a tumbler for a couple of hours with about 1lb of tumbling shot, water and a dash of liquid soap. Tumble for at least 2 hours.

The jump rings will come out smooth (deburred), shiny and ready.




Need a replacement blade or two? I'm sure there are more but I know of a few solid sources:

  • Kevin and Danielle of Potter USA and new makers of the improved Koil Kutter ( Koil Kutter ) sell replacement blades for $11.00

  • Thurston Manufacturing Company ( ) also carries replacement blades which they call THURSTON JEWELER'S SLOTTING SAWS WITH GROUND TEETH. The specific saw type is part # 322 (1.25 diameter, 0.01 thickness, 3/8" hole; 120 teeth). A Dave Arens recommendation.

  • The Ring Lord ( ) High Quality US Made Blade. Made out of M2 high speed steel with a 3/8'' keyed hole. Will cut all softer metals on the jumpringer, and will cut harder materials at an RPM lower than 500. 1.25 inch diameter, 120 teeth. Code: KXJRBLADE8
  • Malco ( ) A Dave Arens recommendation. These guys know their blades. Specific saw options:
    • 1-1/4" .006" 3/8" 120
    • 1-1/4" .008" 3/8" 120
    • 1-1/4" .010" 3/8" 120

  • Rio Grande ( ) Tools and Equipment > Wire Working > Jumpringer > Round Jumpringer System and Accessories: Item # 110162; you need to create an account to access the online catalog.

An important note regarding jeweler's slotting blades. They can vary greatly in quality. Don't shop based on price. Base your vendor selection on reputation. The above vendors should be trustworthy. Dave recommends avoiding no name blades and blades made in China - they're crap. Poor blades may only work on a few rings before the blade fails. Some don't even have teeth!

B. Boni Pienups offers this idea to reduce the wobbling of the slotted plate. 

"I made the suggestion of using nylon washers on the screws. I have several sizes of washers so I can find a combination that is very close to the diameter of the coil sitting in the trough of the KK.  The plate needs to be in contact with the top of the coil, so I like the washers to be just barely short of the height of the coil.  I don't usually use a dowel, which works great, but usually put a wire through the coil and wrap it around the base of the screw before I put the nylon washers on.  This keeps the wire low so it doesn't get into the saw.  After I cut the coil, I just wrap the ends of the wire together to keep the rings contained until I use them."

Boni Pienups
Halftiming in Southwest USA


Why use this kind of tool?

There are many tools available to cut coiled wire into rings. Which tool you choose depends on how you want the cut ends to look.

For jewelry, the ideal cut is for both ends to be flat. This will allow the ends to be push together as close as possible, making the ring look almost closed.

  Standard hardware wire cutters usually have beveled blades. So when cutting, they actually pinch the wire before the actual cut. This pinch readily shows in delicate work like jewelry and may be considered sloppy looking by most people.
  Flush or side cutters are specially designed so one side of the cutter is as flat as possible. On the jump ring, this will create one end that's flat and one end that's pinched. Many folks simply flip the cutters to flush cut the pinched side.
  Dremels and the like come with cut-off wheels. They are hard brittle ceramic discs for cutting through metal. The wheels usually come in various thicknesses, but even the thinnest disc will cut a relatively large gap in a small ring. This can mean when you try to close a round ring, it will become an offset oval.

There are other types of metal and wire cutters, all with their pluses and minuses.

So what will give you an ideal cut for your jewelry jump rings? A jeweler's saw and the power tools designed for cutting coils (Koil Kutter and Jump Ringer). The saw blade or cutter wheel is strong and very thin, so it won't take a big 'bite' out of the ring and leaves both ends flat.

A jeweler's saw is fine if you only need a few nicely cut jump rings. It becomes very inefficient and painfully slow, however, if you want lots of jump rings.

Ah, power tools! ;-)


There's nothing better than having a great tool when you need it. This is one of the best for cranking out lots of jump rings!


Last update to this page: 1 Apr 2012. Send comments, questions or suggestions to Desiree McCrorey.