Earlier I wrote David Butler of Whirlwind a note, requesting some additional information on what looks like very impressive technology.
Although he is quite busy, David replied as follows, adding that he will soon add this information to his web site:
I hope this message will clear up some points regarding Whirlwind Tool safety. I do not have, and likely never will have, any hardware to sell. Instead I hope to get the machinery manufacturers interested in Whirlwind as a win-win and I now have five operational prototypes and each new one is an improvement over the previous versions with still more designs cued up here in the shop. Of course the manufacturers will probably not move until my patents issue, but we are getting closer each day.
My original design goal was to develop a user-controlled and multi-tiered hazard-avoidance system approach with a suitable balance of end-user cost vs. safety features benefit for the various table saw stakeholders ranging from the machinery manufacturers and retailers to the wide spectrum of table saw operators from the novice to the most advanced users. I hope also to curtail some of the table saw litigation that we see by establishing identifiable responsibility for most table saw related injuries, which I believe is to the benefit of all. To that end I now have five operational prototypes with additional models under development.
This particular table saw hazard avoidance concept is designed to offer hazard protection through a series of FIVE simple steps:
First, the operator must easily and conveniently make personal safety-related decisions prior to operation of the saw, by first choosing to use, partially use or to override and even completely remove the hazard avoidance system with the use of a keyed switch.
Second, if the saw is operated in safe-mode, the operator must quickly and simply acknowledge that safety checks have been completed before each and every start of the machine or the saw will not start. This is not an aircraft-pilot-like pre-flight checklist; instead it is whatever the operator wants it to be – or not to be. The point is that once the operator pushes the ARM button and arms the brake to start the saw, (s)he owns the safety responsibility for the following operation. If there is a resulting injury, there is highly unlikely to be litigation blaming the manufacturer of the saw.
Third, through electronic flesh-sensing, an extra margin of safety is provided the saw operator by non-destructive blade braking if the operator’s hands enter the “danger zone” which should always be avoided.
Fourth, each emergency braking event serves as a learning experience and a warning to novice saw operators that they have crossed into dangerous proximity of the saw blade and must rethink their operating practices to insure their personal safety.
Fifth, if the blade-enclosure hazard avoidance system is used, the dangerous, long-feared, and unpredictable table saw “kick-back” phenomenon is eliminated.
Each time the saw is stopped, either through a normal stop or a flesh sensing emergency stop, the saw will revert to the amber light safe condition. The emergency flesh sensing stop is completely non-destructive. Neither the blade, nor the circuitry, nor the saw are damaged during the stop and the operator may simply correct the dangerous condition, rearm the flesh sensing brake circuit and resume sawing. Think safety twice, cut once.
I also received from David a Word document, with links to Reference Documents and Related Website Links. Simply click on the link, and you will be able to download the document. Butler requests that we “…Give credit as appropriate to the source, especially the safety poster, which they were kind enough to allow me to use…”
— Al Navas