Intro: Rolling Mouse Rotary Cutter
One day in the fabric store I happened to be browsing at all the different cutting tools and an elderly lady stopped by too to look at all the scissors on display. She was intently studying all the scissors. I pointed at the rotary cutters and said they worked well. She then said, “Do you sew?” My instinct was to respond, “I am Batman.” but I explained I had bought a rotary cutter recently and liked how it worked. She said she had trouble squeezing the scissors when using them. She was looking at what were supposedly more ergonomically designed scissors. I recommended she try the rotary cutters since you can just press down and roll the cutter to cut.
So that kind of stuck in my mind that makers are always developing tools to do things better and more efficiently. I saw recent mention of this ATMaker group hacking and modding things for assistive technology so I thought I could do something with this to contribute to the cause. Everyday tasks that we ordinarily take for granted, like using scissors in crafting, can certainly be improved for use by all.
This project is really the first prototype to see if some attachment can be made to adapt the rotary cutter so that it can be used by someone with physical challenges.
Step 1: En Garde...
There are many rotary cutters out on the market. They use a razor sharp disc or wheel to cut. They are great in fabric cutting where you have a long line to cut. Make sure you use one with a cutting mat under the material being cut. Curves are a little bit trickier but can be done with practice. You hold it by the handle and roll the cutting disc to where you want to cut. Applying pressure makes the blade guard move out of the way and brings the cutting disc into contact with the material. I was apprehensive at first about getting one since I knew how hazardous single blade utility knives are but they are safe to use. You get to know where you have to sight the cut line and guide the rotary cutter.
For best use, the blade must be held upright for a clean cut and even pressure applied while rolling.
So the idea was to make some kind of attachment that acts as "training wheels" to keep the cutter perfectly upright and stabilize the movement when used.
I used 5/8" Roller Ball Bearings also called ball transfer units, sometimes mounted in rows for sliding heavy packages or lumber over. Since they are a mounted rolling ball, they are capable of moving in any direction without needing to pivot like wheel casters. They do have transfer units with a nylon ball instead of steel. I don't know if the nylon ball would roll better on fabrics. Making some kind of sled or skateboard with two roller balls would make a stable 3 point rolling cutter.
The other consideration to address was that you need to press down while rolling in order to cut. With the rotary cutter mounted in the sled, we can make a nice wide paddle piece that will act as an additional blade guard and a press point to operate the cutter. There are mouse type cutters for cutting picture frame border mats but they seem to provide poor visibility of the cutting edge and wouldn't be able to ride over rough surfaces like fabric.
Step 2: Timber...
I had a piece of craft wood actual 1/2 x 1 1/2 inch stock to use.
With the rotary cutter in place, I marked out all the measurements to size.
Place the roller balls in position to make a wide enough base.
Two small pieces for the uprights to sandwich in the rotary cutter handle.
Cut a piece that is the upper guard - press plate.
Since this is a hand tool, I wanted to round all the edges and shape the upper piece to be more ergonomic for better gripping to fit the hand. Note that the shape was geared more for use for right-handed persons. I did the video demo with the left hand since the right hand was operating the camera. You should adjust accordingly for whoever the user might be, also bigger or smaller depending on the person.
Design so that the blade guard lock and the thick/thin fabric cut setting are accessible and functioning.
Step 3: Momma's Got a New Pair of Skates...
Time to glue the pieces together.
It's nice if you have a micropinner nail gun to tack the small pieces together but you can just hold it together until the glue grabs or use tiny clamps. I guess you could do other joinery but just wood glue only is strong enough for this purpose.
Position your rotary cutter in place so that you can build around it to get the exact fit. I had to adjust the position the upper press plate so that I could wiggle the cutter handle in and out to make the device removeable.
Once everything was dry, I sanded again and gave it a few coats of poly/stain.
When that was dry, you can mount the roller balls.
The smallest screw I had to mount the rollerballs was too long for the thickness of the bottom wood piece so I added a layer of wood popsicle stick to bulk up the bottom. The inner screws luckily were under the uprights so they could extend into there. I had to build up the height of the outer screws with washers so that they wouldn't poke out the other side.
Insert the rotary cutter back into the holder. My rotary cutter has rubber handles so that helped with the friction fit. You can drill some holes to mount in some nylon tie-wrap straps or a set screw for a more permanent secure fit.
This was my approach for a solution. 3D modeling and printing is another.
Now get out there and make.