I read that article back when I was searching for a good way to cut rings. Hand cutting for me just was to time consuming. If your crafty, a dremel most certainly could be substituted for the drill. With a supply of scrap wood and time.....by all means doable. Extream care needs to be employed when using that design, but a guard for the saw would be easy to make. I had some personal questions about the set-up concerning power of my Dremel vs dia of saw blade (not knowing at the time what was possible) Time of construction/space of final product/ease of set-up for different coil sizes(yes different hole sizes for differend gages of wire and ID's of coils). I have gone this route before in different applications mostly in the construction of different projects involving power tools and jigs to mimick better tools I was not ready to purchace. IE table saws using plywood and circular saws/routers attached to again plywood for using as a router table and so forth with mostly success, but consistantly was difficult without fussing around. Money was saved but I have found that the set-up time on most of these home made units very time consuming let alone trial and error. (think scrap silver $) I eventually would abandon my homebrewed jigs for the real thing as money would allow.
The unit shown was made for the construction of chainmaille armor rings where the finish of rings is not really of the same quality as fine silver work. Again not that its a bad thing. Repeteability,quality, and ease of use was the main factors I felt was important to me, for anything less would take the joy out of creating something quality.
Calulate carefully what it would take you, time and money, to construct such a jig and weigh it against buying something that will give you consistant quality cuts with ease of use not to mention the space such a jig would take-up and ofcourse the safety factor. Again think "power tools".
I personally not wanting to spend much $ and allready owing a Dremel myself went with a Koil Kutter. Its small, easy to store, easy to set-up,Quick to use, safe.The cut is very nice and the price was right. Are the other units better? yes but also much more money.
Bottom line....This unit (scrap wood) will work but IMO would spend the $ on a cheap Koil Kutter. Money and time better spent on your work.
The best of luck, and watch those fingers.
Dan