Hi, Team! I’ve got a new hobby making paper flowers. I use a few different stencils to trace the petals onto paper, then I cut them out with scissors. It takes a lot of petals to make a flower, so I wondered if I could have the CNC cut them out for me. It would be easy enough to create a tool path to match the stencils. Can a razor be attached the spindle, and if so, is there a way to shut off the spinning action so it just drags the blade along the toolpath?
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If you’re intent on cutting paper on a CNC (versus a laser or vinyl cutter) then a drag knife is your best bet. There are idiosyncrasies you have to plan for such as corner loops but the result is exacting and clean. The brand most known for CNC drag knives is Donek. That said, if you’re just wanting to give it a try then make a 3D printed drag knife to start.
Hold down is actually a challenge with a medium like paper. That’s why my preference for cutting paper is on a vinyl cutter using a low-tack mat, the latter holds everything in place while cutting. If a “toasty fringe” isn’t a problem for your project then the fastest and easiest way to cut paper is the laser, but you’d have to turn off air assist or your paper will go flying.
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If the vinyl cutter intrigues then here’s a good overview of the process.
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I can’t believe I pay $100 a month for this dream facility! Beyond all the machines and tools I have access to, there are people like you who respond within an hour to just about any question I ask.
Thank you for the info, Travis!
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SST came out recently with their own drag knife. It is less expensive than Donek. Amazon
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We also got a Cricut Maker 3 donated recently that will be set up in the next few weeks, is if 12x12 is an OK size for your project you can soon use that for it 
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I haven’t used a Cricut but I have used the very similar Silhouette; it’s great for cutting paper on a tack mat like Travis mentioned. I used it to make paper gaskets for a carburetor.
You asked if the spindle can be set to not spin, the answer there is yes.
We have a pen adapter for the CNCs in one of the community bit boxes, you want to ensure the spindle isn’t spinning when you use that. The pen adapter lets you use the CNC to draw with a Sharpie which could automate the stencil tracing part of your process, which probably won’t save you a ton of time / effort.
You need to have the spindle not spin when a Sharpie is attached to the CNC, otherwise the centrifugal force will spin all of the ink out of the Sharpie and splatter everything around it. Obligatory: “Ask me how I know?”
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That is cool that you cut paper gaskets with a silhouette. I recently had a need for a gasket and used a laser to cut it.
I had mixed success cutting single layer cardboard using a drag knife (@JoeN 's, actually) on the CNC. But I mainly had issues when I went to thicker stock; the drag knife couldn’t turn and cut cleanly due to the thickness. I also wanted some fairly tight turns on those cuts. I think it could work well with paper and poster board and more reasonable cuts.
The biggest issue is you need a pretty flat surface with a good vacuum hold, which, given the other users of the CNC, means you can probably only do cuts in narrow windows of time, right after the spoilboard is replaced or resurfaced.
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Why not laser?
Lasers can do paper really, really easily
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Danny has a good point; I’ve cut paper and poster board many times on the laser. The actual edges will be burnt of course, but it shouldn’t show on either face with the right settings.
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