3047: Rotary Tool

2025-11-18T18:23:51Z

2001:14BA:A070:6700:CD04:D8A5:1849:E618: /* Explanation */

{{comic
| number = 3047
| date = February 5, 2025
| title = Rotary Tool
| image = rotary_tool_2x.png
| imagesize = 528x468px
| noexpand = true
| titletext = It was great until my thumb slipped and I accidentally launched my telescope into the air at Mach 8.
}}

==Explanation==
It is common to find multipurpose handheld tools that can function as higher-speed drills and lower-speed screwdrivers, switching between modes with a slider. The tool in this comic appears to have extended that concept to the extreme, covering both very high-speed and very low-speed tools. Presumably the tool has a rotating part at one end that can accept multiple attachments to facilitate the different uses.

All of these speeds are sensible for the specified uses. However, engineering a single tool to perform reliably across the required range of speeds is likely to be deeply impractical. Equally, designing the base unit such that it can be usefully employed to all these purposes would be a substantial challenge. For example, a household drill needs to be both portable and reasonably bulky, whereas a record player needs good stability, and a dental drill needs to be small enough to be moved flexibly and delicately. In any case, it's highly unlikely that any individual would have a need for all these uses,{{citation needed}} so the market for such a tool would be extremely limited.

The title text highlights one of the downsides of combining functions in this way — the potential for using the wrong setting for the task at hand, by carelessness or clumsiness, with detrimental effects. In this case, while attempting to use the "sidereal telescope mount" option with an actual telescope, the user accidentally changed the tool to a much higher speed setting, launching it into the air, on a ballistic trajectory with {{w|hypersonic speed}} (specifically Mach 8, or roughly 5,930 miles/9540 kilometers per hour, which actually surpasses the current record-holder for the highest speed ever recorded by a crewed, powered aircraft, the {{w|North American X-15}} (Mach 6.72 / 4,520 mph)). More commonly, attempting to insert a screw while on the drill setting could cause damage to the item being screwed together, the screw itself, or the screwdriver bit.

The precession setting refers to the {{w|Precession of the equinoxes|precession of the equinoxes (axial precession)}}, which happens on a 26,000-year cycle that corresponds to the {{w|Revolutions per minute|RPM}} rate shown. The average person does not need to adjust their telescope for such minor shifts, certainly not on a constant basis. This may be beneficial for scientists making precise measurements but they would have more powerful and dedicated tools to this end. For commercial use by the public, this would not be remotely necessary.

The {{w|Dremel#Rotary tools|Dremel}} tool referred to is a high-speed, low-torque {{w|rotary tool}} that can be fitted with a variety of bits for cutting, sanding, grinding, sharpening, polishing, engraving, machining, etc. The speed of the dental drill might seem excessive, but according to [https://sableindustriesinc.com/what-is-a-high-speed-handpiece-how-it-works-speed-more/ Sable Industries], a manufacturer of high-speed dental drills, they can run "at speeds of between 300,000 and 450,000 RPM." They squirt water as they rotate to cool the bits down, so they don't overheat (a further design complication for this multitool).

The speeds labeled "record player" are intended to correspond to standard rotational speeds of {{w|Phonograph record|phonograph records}}. The intended playback speed standardized at 78 rpm (not 72 rpm as depicted in the comic) in the 1920s, with a record diameter of 10 inches. The speed and size, as well as the required width of the groove encoding the music, dictated a playing time of about 3½ minutes per side; collections of 78 rpm records were released as albums. Beginning in the late 1940s, records designed to be played back at 33⅓ rpm (close enough to the 33 rpm in the comic) were produced, to allow longer play times (hence the LP designation, for "long play") on similar-sized records, which standardized on a 12 inch diameter. This was commonly used to release an collection of songs on a single disc, still called an "album", totaling about 22 minutes per side. Concurrently, an alternative format, 7 inch diameter records designed to be played at 45 rpm, was produced, allowing about 5 minutes per side. This was often used to release "singles" (a single song on each side of the record). The 33⅓ and 45 rpm playback speeds supplanted 78 rpm, and remain the standards today.

{| class="wikitable sortable" style="margin: auto"
|-
! Function !! Speed (rpm) !! Rotation / Revolution Period !! Diameter of Bit for Mach 8 Launch Speed !! Notes
|-
| Sidereal mount precession adapter || 0.000000000073 || ~26,000 years || 4799 au || see {{w|axial precession}}
|-
| Sidereal telescope mount || 0.00070 || 23.93 hours || 74,866 km || rotates once per {{w|Sidereal time|sidereal day}}
|-
| Hour hand on a clock || 0.0014 || 12 hours || 37,733 km || Typical 12-hour analog dial (as opposed to a {{w|24-hour analog dial}})
|-
| Minute hand on a clock || 0.017 || 60 minutes || 3,144 km
|-
| Second hand on a clock || 1 || 1 minute || 52.4 km || By definition a second hand rotates at 1 rpm because it completes a single rotation each minute
|-
| 33 rpm {{w|Phonograph|record player}} || 33 || 1.8 seconds || 1,588 m || It's actually 33⅓ rpm
|-
| 45 rpm {{w|Phonograph|record player}} || 45 || 1.3 seconds || 1,165 m
|-
| 72 rpm {{w|Phonograph|record player}} || 72 || 0.8 seconds || 727.9 m || probable typo for 78 rpm
|-
| {{w|Screwdriver#Powered screwdrivers|Screwdriver}} || 300 || 0.2 seconds || 174.7 m || Screwdrivers rotate much slower than similar looking drills to avoid stripping the screws
|-
| Drill || 1,500|| 40 milliseconds || 34.9 m
|-
| Airplane propeller ||2,500|| 24 milliseconds || 21.0 m
|-
| {{w|Dremel#Rotary tools|Dremel}} || 35,000 || 1.7 milliseconds || 149.7 cm || The speed of a basic Dremel, many Dremel tools have variable speeds from 5,000 to 35,000 rpm
|-
| {{w|Zippe-type centrifuge|Uranium enrichment centrifuge}} || 60,000 || 1 millisecond || 87.3 cm
|-
| {{w|Dental drill}} || 300,000 || 0.2 milliseconds || 174.7 mm
|-
|}
[Notes:
1) All speeds are rounded to two significant figures, which may result in some variance from the intended result when trying to calculate revolution times from them.
2) Mach 8 launch speeds based on stated RPMs
3) Mach number is actually defined by the local thermodynamic temperature. All the above will be based around the velocity at {{w|Standard temperature and pressure|STP}}, or thereabouts, although the larger radii would necessarily involve travel through higher latitudes, into space or far beyond, where such a measure rapidly becomes meaningless.]

==Transcript==

:Multi-function rotary tool

:[A close-up of a stick-shaped tool, where on the side of a section is a panel with a slider adjustable in various levels annotated with numbers and texts. Besides the panel there are some invisible inlays. One visible end of the section is attached to another section.]
:<u>Speed (rpm)</u> <u>Function</u>
:0.000000000073: Sidereal mount precession adapter
:0.00070: Sidereal telescope mount
:[Following three are labeled "clock hands":]
:0.0014: h
:0.017: m
:1: s
:[Following three are labeled "record player":]
:33: 33
:45: 45
:72: 72
:300: Screwdriver [Current setting]
:1500: Drill
:2500: Airplane propeller
:35 000: Dremel
:60 000: Uranium enrichment centrifuge
:300 000: Dental drill

{{comic discussion}}

[[Category:Telescopes]]

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3047: Rotary Tool