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| SawStart |
 Title text: Unfortunately, SawStart is one-use-only. Once started, the blade cannot be stopped, and must be replaced with a fresh blade while the running one is carefully disposed of. |
Explanation
SawStop is an American table saw manufacturer whose product is designed to increase safety. Table saws can be highly dangerous if not used properly, because they feature a rapidly spinning circular saw protruding from the surface. If any part of someone's body comes into contact with the blade while it's spinning, it can cause severe injury or death. In general, it is not wise to touch even a normal stopped blade without being absolutely certain that the power cannot be turned on and the blade is not sharp enough to be dangerous at rest. SawStop products feature an automatic brake, designed to detect when flesh comes into contact with the blade. According to manufacturer claims, the brake (an aluminum block) will stop the blade within 5 milliseconds of detecting contact, followed by the blade retracting into the table. This is intended to prevent major injuries in the event of contact.Here, Black Hat takes the notion of a product designed to increase safety, and changes the design to do the opposite, making it much more dangerous. Like the SawStop design, his product ostensibly detects contact with skin and reacts within milliseconds, but rather than stopping the blade, his product uses an explosive charge to start a stationary blade. Simply turning a stationary blade on in the event of contact would be bad enough, but the explosive device implies very rapid acceleration, and might work even if the tool is turned off and unplugged (usually a safe condition for working with saw blades). This 'feature' is specifically designed to run up to significantly damaging speeds the moment it is touched, likely causing severe injury. There is no benefit to such a system, and it exists solely to be malicious, which is likely why it's "less popular."
The title text refers to the fact that the braking feature on the SawStop is single use. Because of the very fast response time, both the braking cartridge and the saw blade will be badly damaged in the process, and both will need to be replaced (this being considered preferable to the kinds of permanent injuries that can result from a spinning blade). The SawStart is also single use, but in its case, it somehow makes the blade impossible to stop, violating the second law of thermodynamics (and probably several other laws). Hence, the SawStart blade must also be replaced and disposed of, but this apparently has to be done while the blade is spinning. To attempt to remove a spinning blade is incredibly dangerous, and this simply adds to the unnecessary harm this product could do. Disposal would also be complicated, because the still-spinning blade could cause damage to whatever is chosen to contain it.
In theory, such a system could be useful on a futuristic mechanized melee weapon (like "chainswords" from Warhammer 40,000). In that case, the saw would start spinning as soon as it hits the enemy, removing the need to allow time for it to spin up. On top of that, the saw is impossible to stop, and will continue to rip and shred any enemies in contact until the saw breaks. Such a combat disk saw may need to be redesigned so that it is activated by armor and flesh alike.
A similar attempt at taking a safety feature and flipping it on its head was done in 2876: Range Safety, this time with the range safety officer being accompanied by a range danger officer.
Transcript
- [A table with a table saw stands behind Black Hat who gestures to the table while facing Megan and Cueball. There is a label on the side of the table, a logo of a circular saw blade, with the first part of a word inside the blade:]
- SawStart
- Black Hat: When the saw detects contact with skin, an explosive charge starts the blade spinning at full speed within a few milliseconds.
- [Caption below the panel:]
- SawStop's less-popular competitor
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