3047: Rotary Tool

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Sailing Rigs

|< < Prev #3193 (January 12, 2026)

Title text: I wanted to make the world's fastest yawl, so I made the aft sail bigger, but apparently that means it's not a yawl anymore! It's a real ketch-22.

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Explanation

This is one of 60 incomplete explanations: This page was created by the birds flying in my kite. Don't remove this notice too soon. If you can fix this issue, edit the page!

This comic shows the side profiles of a variety of different sailing boat/ship rigs, not all of which are real. The first six which are listed are real, as well as the tenth, but none of the others are. A Flettner rotor (shown in the tenth one) is a cylinder with disc end plates which is spun along its long axis, generating force at a right angle to the direction of the wind.

• Lateen: a single triangular sail.
• Bermuda rigged sloop: a front and rear triangular sail share a mast.
• Ketch: two triangular sails as above, with an additional triangular sail on a second rear mast.
• Gaff rigged sloop: front triangular sail shares mast with rear quadrilateral sail.
• Yawl: two triangular sails share front mast and a much smaller aft mast holds a small aft.
• Schooner: two triangular front sails share foreward mast with quadrilateral center sail. An aft mast supports a quadrilateral aft sail.
• Ketch-rigged gaff: The first fictional rig. Resembles a gaff, with the aft sail reduced and two triangular sails mounted above. The resulting shape resembles a vertical ketch.
• Kloop-rigged sketch: A mixture of the names of ketch and sloop, poking fun at the unfamiliar names of some rigs.
• Bunkbed rig: A gaff-rigged sloop is mounted on top of a second hull.
• Flettner rig: The rectangular outline of a cylinder with motion lines around it, indicating a Flettner rotor.
  • Flettner rotors were previously mentioned in 3119
• Oops, all spinnakers: three masts each with a sail only attached to the top.
• Keel rig: three sales in a ketch arrangement, but mounted to the keel, which would typically put the **sails underwater**.
• Kite rig: all sails are replaced by two groups of kites, each tied to the mast with an independent line.
• Longsail rig: bermuda rigged sloop with the aft sail extending ~5 times as far back, well beyond the end of the hull.
• Deckhand obliterator: all sails replaced by an anchor that swings around the mast on a chain, similar to tetherball. Any deckhands (crew) on the deck could be knocked off or fatally hurt if the anchor passes through their space.
• Offset rig: gaff rigged sloop sails are mounted on a mast that is offset (forward) from the hull via an underwater extension of the keel.
• Mastless rig: a single sail is attached where the mast would normally be mounted, flapping around freely. This provides much less propulsion or steering.
• Unclassifiable chaos rig: includes elements of the schooner, yawl, lateen, and possibly others.

The title text is a pun on a Catch-22, a no-win situation in which the thing needed to succeed would cause it not to succeed or not to be necessary. For instance, "the only way to qualify for a loan is to prove to the bank that you do not need a loan." Per the main panel, a ketch is similar to a yawl but has a larger aft sail, so increasing the aft sail of a yawl effectively turns the yawl into a ketch.

Transcript

This is one of 37 incomplete transcripts: Don't remove this notice too soon. If you can fix this issue, edit the page!

[The comic contains views from the side of boats, each with a different sailing rig. All boats are oriented to the left of the comic.]

• Lateen: a single triangular sail.
• Bermuda rigged sloop: a front and rear triangular sail share a mast.
• Ketch: two triangular sails as above, with an additional triangular sail on a second rear mast.
• Gaff rigged sloop: front triangular sail shares mast with rear quadrilateral sail.
• Yawl: two triangular sails share front mast and a much smaller aft mast holds a small aft.
• Schooner: two triangular front sails share foreward mast with quadrilateral center sail. An aft mast supports a quadrilateral aft sail.
• Ketch-rigged gaff: The first fictional rig. Resembles a gaff, with the aft sail reduced and two triangular sails mounted above. The resulting shape resembles a vertical ketch.
• Kloop-rigged sketch: A mixture of the names of ketch and sloop, poking fun at the unfamiliar names of some rigs.
• Bunkbed rig: A gaff-rigged sloop is mounted on top of a second hull.
• Flettner rig: The rectangular outline of a cylinder with motion lines around it, indicating a Flettner rotor.
• Oops, all spinnakers: three masts each with a sail only attached to the top.
• Keel rig: three sales in a ketch arrangement, but mounted to the keel, which would typically put the **sails underwater**.
• Kite rig: all sails are replaced by two groups of kites, each tied to the mast with an independent line.
• Longsail rig: bermuda rigged sloop with the aft sail extending ~5 times as far back, well beyond the end of the hull.
• Deckhand obliterator: all sails replaced by an anchor that swings around the mast on a chain, similar to tetherball. Any deckhands (crew) on the deck could be knocked off or fatally hurt if the anchor passes through their space.
• Offset rig: gaff rigged sloop sails are mounted on a mast that is offset (forward) from the hull via an underwater extension of the keel.
• Mastless rig: a single sail is attached where the mast would normally be mounted, flapping around freely. This provides much less propulsion or steering.
• Unclassifiable chaos rig: includes elements of the schooner, yawl, lateen, and possibly others.

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Discussion

How come it's at 0.017 RPM for a minute?? and yet 1 RPM for a second? pls fix this randall Midnightvortigaunt (talk) 18:01, 5 February 2025 (UTC)

Its 0.017 RPM for the minute hand. The minute hand revolves once per hour or at 1/60 RPM ≈ 0,017 RPM --172.71.148.59 18:14, 5 February 2025 (UTC)

Ohhh that makes sense I didn't think about it like that Midnightvortigaunt (talk) 19:27, 5 February 2025 (UTC)

Mr.Dude (talk) 17:20, 7 February 2025 (UTC) I wonder what torque is needed to launch the average backyard telescope worthy of a tracking mount at Mach 8 given standard state pressures and temperatures of perhaps average conditions found in Randall’s back yard.

How come the comment above is invisible to me? 172.68.245.229 18:03, 5 February 2025 (UTC)

Possibly because people indented with spaces rather than with colons? 162.158.79.77 19:40, 5 February 2025 (UTC)

72 RPM for a record player...? 162.158.74.25 18:08, 5 February 2025 (UTC)

I could only find 78 RPM disks in the german wikipedia. 172.70.114.56 18:41, 5 February 2025 (UTC)

I came here to make the same comment: 72 is most probably a typo. The old records (at this date, very old, since the transition to vinyl records was 1948 to 1958 (in the US)) were 78 rpm, not 72 rpm https://en.wikipedia.org/wiki/Phonograph_record Rps (talk) 19:30, 5 February 2025 (UTC)

72 is (for example) relevent to font sizes (size 1 = 1/72 of an inch, size 72 = 1 inch), which might therefore have envaigled Randall's head for numbers by a different route, and got him confused. Conceivably he has had to deal with playing old 78s, but probably not for a long time... even the retro-revival of vinyl, recently, has probably not had quite so many old old records released to fill such nostalgic needs. So an easy brain-fudge/thinko to trip over on. 162.158.74.48 00:54, 6 February 2025 (UTC)

There used to be a record label call 72RPM records. 172.69.229.146 (talk) 19:07, 5 February 2025 (UTC) (please sign your comments with ~~~~)

We need one of those tables in here. DollarStoreBa'al (talk) 18:37, 5 February 2025 (UTC)

I made a change to the explanation that all of these numbers are realistic because, I checked out the speed of dental drills and they really do rotate that fast. I haven't checked out all of the other tools, but I suspect that they are also accurate. If you find that any of them are misstated, please correct my correction. Rtanenbaum (talk) 22:38, 5 February 2025 (UTC)

TABLE REQUEST When someone uploads a table, I'd like to recommend a second column for the frequency / reciprocal of the speed. "0.000000000073 minutes" is one every 13.7 billion minutes, or ~26,000 years. Thanks! 172.70.46.107 20:20, 5 February 2025 (UTC)

Me again. Should the column header "revolution time" be "rotation time"? In every instance, the axis of motion is within the object itself; even the second/minute/hour hands go around the axis. 141.101.76.73 16:41, 6 February 2025 (UTC)

TRIVIA 16 2/3 RPM phonographs were used for some voice-recorings back in the day. 172.68.26.24 21:01, 5 February 2025 (UTC)

My parent's old record player (60's, probably) had 4 possible speeds: 16, 33, 45, 78. By the early 80's the current ones only had 33 and 45. Rps (talk) 16:59, 7 February 2025 (UTC)

Album goes back to stacks of 78s. A symphony or opera would be 2, 3, 4 or more disks. They were bound like a photo-album with a leaf for each disk. "78" wasn't "standardized" until the format was fading. 3600-rpm motor and 46-tooth gear is incomplete (one tooth gear??) Early discs were from 60 to 130 rpm. Users would adjust speed by ear (also to ease pitch-matching for karaoke). Only as LPs arrived did someone invent the number "78.26 rpm" (no recordplayer and few lathes of the period were near that accurate). --PRR (talk) 02:34, 6 February 2025 (UTC)

Indeed, my parents had a large collection of old records and at least one had a speed marking of 80rpm.--172.68.186.43 09:17, 6 February 2025 (UTC)

With wind-up players, a lot of them started off playing at one speed and ended playing at a completely different one anyway...172.68.186.50 09:43, 6 February 2025 (UTC)

I suspect there's not many consumers needing a Uranium Enrichment Centrifuge... at least outside of a few countries in the Middle East. --172.70.58.6 08:50, 6 February 2025 (UTC)

Might face some regulatory / export license issues too.172.70.86.129 11:34, 6 February 2025 (UTC)

I feel like there was a lost opportunity to have Dr. Who's Sonic Screwdriver on the list. Maybe the rpms are unknown.162.158.159.107 13:05, 6 February 2025 (UTC)

The table says that 0.00070 "seems off; a sidereal day is 23.93 hours". That's just because (like all of the other settings) 0.00070 is quoted with only 2 significant digits. Every period between 23.64 and 23.98 hours would round to 0.00070 RPM. 162.158.134.199 13:58, 6 February 2025 (UTC)

The question I have is: why are dental drill speeds so high? 172.70.247.92 17:21, 6 February 2025 (UTC)

"why are dental drill speeds so high?" It hurts less. (Are you old enough to remember routine use of belt-driven dental drills?) You can cut a given amount of material (wood, steel, tooth) quickly with heavy force or high speed. Neither is really fun, but hi-speed is generally preferred. --PRR (talk) 19:08, 6 February 2025 (UTC)

Although some materials behave badly to heat (either work-hardening, for some alloys, or melting/burning, like plastics) and that's why variable-speed hand-drills/etc usefully have low speeds (for essentially the same force, when that's done via reostat rather than an actual gearbox). On the few occasions I've had my teeth drilled, I'm pretty sure I've detected the pungent smell of fried tooth-fragments, but it was nothing like as strong as smelling my own nose-flesh being burnt one of the times I had it cauterised to try (and fail) to prevent excessive nosebleeds. 172.69.79.139 21:15, 6 February 2025 (UTC)

The latest NMR CPMAS probes send their rotors to go at 9.6 Mrpm, M=mega. [1] --172.69.109.172 21:56, 7 February 2025 (UTC)

Should we list the rotor diameters to achieve the mach 8 speed mentioned in the title text in the table? I don't think that we should. guess who (if you desire conversing | what i have done) 06:01, 24 February 2025 (UTC)

I (obviously since I worked it all out) think it is in the spirit of the ridiculous idea of the comic and XKCD generally to do these calculations. That said, I'm getting different numbers than your update to make it Mach 8. Denver87 (talk) 16:21, 24 February 2025 (UTC)

I get the following: 4,799au, 74,866km, 37,733km, 3,144km, 52.4km, 1,588m, 1,165m, 728m, 175m, 34.9m, 21.0m, 149.7cm, 87.3cm, 174.7mm. Denver87 (talk) 16:21, 24 February 2025 (UTC)

Happy to share calculation notes, but here's the example for the dental drill: 300,000rpm = 5,000 rps; diameter of: 174.7mm --> circumference of: pi * 174.7mm = 548.8mm; 548.8mm * 5000rps = 2,744,000mm/sec = 2744m/sec; Mach 8 = 8 * 343m/sec = 2744m/sec. Denver87 (talk) 16:21, 24 February 2025 (UTC)

If you agree with the calculations, one of us can at least update it. Denver87 (talk) 16:21, 24 February 2025 (UTC)
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