2334: Slide Trombone

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Slide Trombone
Remember the CPS 2000, the super soaker that was discontinued because it was too powerful? Relatedly, can I borrow your tuba?
Title text: Remember the CPS 2000, the super soaker that was discontinued because it was too powerful? Relatedly, can I borrow your tuba?


In this comic, Megan carries her "old" trombone, a brass musical instrument with a movable sliding piece used to change a musical note's pitch, which those offscreen apparently haven't caught sight of since the 90s (presumably the 1990s). These offscreen people don't suspect anything unusual of Megan's trombone until it turns out that it contains a water gun, which she uses to soak the other characters. It is unclear whether she has somehow hidden the water gun inside the trombone, has disassembled it to produce a hybrid trombone/Super Soaker device, or otherwise modified the trombone such that it can shoot water as a water gun would.

In the second panel, she is priming the water gun by pumping air into it, following the sequence of pump actions used for the Super Soaker. During the first "slide" action, the user pulls the grip towards themselves, increasing pressure within the water reservoir of the gun. During the second "hiss" action, this grip is pushed away; a valve prevents air leaving the chamber, though a small amount usually leaks out. Part of the joke here is that a slide trombone also has a slide mechanism, held in a similar way as that of the Super Soaker, but which serves a completely different purpose. In the case of the trombone, when the slide is extended, the total length of tubing between the mouthpiece and the bell is extended, thereby lowering the pitch of the sound that is produced (there is, however, no comparable air chamber). This similarity between the two devices enables Megan to use the trombone's slide as if it were a Super Soaker's.

In the third panel, she presses the trigger, causing the compressed air within the water reservoir to push water from it at high speed, hitting the off-screen targets. One cries out in surprise, while the other expresses the realization of what had happened to their lost Super Soaker (that Megan had taken it as an alteration to her trombone).

In the title text, Megan asks those offscreen about the CPS 2000, a water gun which, as is mentioned, was powerful but too powerful, causing injuries to those shot by it and allegedly leading to its discontinuation. Megan then, in connection with her previous question about the Super Soaker, asks to borrow a tuba, most probably to hide the CPS 2000 water gun inside. Her reasoning behind needing this tuba seems to be that the CPS 2000 is seemingly larger than the Super Soaker originally stored in Megan's trombone and thus would require a larger vessel (this use of the tuba may be cause for loss of friendship with an experienced player).

The CPS 2000 referenced by Megan was developed primarily by Lonnie Johnson (inventor) and Bruce D'Andrade for Larami's Super Soaker product line. The "CPS" within its name refers to the "Constant Pressure System" used in certain water guns (its technology can be seen in this patent by Bruce D'Andrade). In this system, a rubber bladder within the water gun is pressurized by the user's pumping action, which draws water from a reservoir and pushes it into the pressure chamber, filling the bladder like a balloon. Once the desired volume of water is stored within the toy, the water can be released by means of a spring-loaded trigger and valve system. Upon release, the rubber bladder pushes the water out of the pressure chamber and out of the front nozzle, hitting whatever targets the user desires it to. The "constant pressure" of the CPS's name refers to the fact that the bladder will exert the same pressure on the water throughout the shot, ensuring consistent power and range, as opposed to air pressure Super Soakers, whose power will die off during the shot as the pressurized air within the pressure chamber expands, expelling the water but reducing the pressure in the toy.

The Super Soaker that Megan uses in this comic is also referenced in 220: Philosophy and 517: Marshmallow Gun. If the water gun featured in this comic is the same as that depicted in previous comics, it would likely be a Super Soaker 50, the first widely available pressurized water gun. It could also be the less common but earlier model the Power Drencher or the later SS 50 Classic Series, Super Soaker S.E., or the 20th anniversary SS 50 rerelease.


[Megan walking along carrying a trombone.]
Offpanel voice #1: Hey, her old trombone.
Offpanel voice #2: Cool, I haven't seen that thing since the 90s.
[Four quick shots of Megan moving the trombone's slide back and forth. It makes sound, but not like an ordinary trombone.]
FX: Slide
FX: Hisss
FX: Slide
FX: Hisss
[Megan does something else with the trombone, and it shoots water at the offpanel observers.]
FX: Pshhhhh
Offpanel voice #1: AUGH!
Offpanel voice #2: So that's where my Super Soaker went.

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I can't find any source saying that the CPS 2000 was discontinued because it was too powerful. There's plenty of reasons why products get discontinued, and this product had various points of criticism apparently. --NeatNit (talk) 21:09, 17 July 2020 (UTC)

It's not verified but it appears likely. The nozzle of the CPS 2000 was 2.5x larger than advertised on the box and had a prominent safety warning affixed to it. It shot water with higher pressures than ever before. There was a hullabaloo around somebody losing an eye from it; there's no proof this happened but such hullabaloos are still bad for business. The model was discontinued and no water gun with comparable power has ever been mass produced for consumers since. It's notable that you can shoot water with as much pressure as you want to the point of cutting metal from a distance (see water cutter, found in well funded makerspaces as an improvement from the laser cutter, plasma cutter, cnc machine) and the metal of a brass instrument could be made to hold higher pressure than plastic. CPS 2000 information from https://nerfpedialegacy.fandom.com/wiki/CPS_2000 23:58, 17 July 2020 (UTC)
Industrial water cutters use an abrasive (often garnet), as it is hard cut a material with something softer than that material. The water isn't doing the cutting, it is just there to provide pressure. In theory a high enough pressure pure water jet would cut metal, but it probably wouldn't be clean. To quote Randall, imagine throwing a ripe tomato into a cake. Probably not Douglas Hofstadter (talk) 05:05, 18 July 2020 (UTC)
For clarity, these cutting machines usually referred to as water jet cutter (or "waterjets"), rather than "water cutters." JohnHawkinson (talk) 12:59, 18 July 2020 (UTC)

There are actually two versions of the CPS 2000, and although it is true the original version is the most powerful retail super soaker, the mk2 version was only slightly less powerful. Several water guns were released 1996-2000 with comparable power. Take the CPS 2500 - it was released 2 years later in 1998 with the same pressure chamber as the mk2 CPS 2000, while adding a nozzle selector. It is my personal belief that Laramie (the company behind Super Soakers) actually shortened the pressure chamber in the mk2 to make it more reliable, not to make it safer. The mk1 longer bladder chamber (and associated higher pressure) can cause the firing valve to get stuck closed by the high pressure behind it, causing trouble as either the trigger broke or users over-pressurized and burst the bladder. Could be wrong, but you can only work with so much pressure using plastic parts. In any case, my source on the question of comparable power http://www.isoaker.com/Armoury/soaker_listing.php has a list of all known water guns sortable by their output, range, power, reservoir size, etc.; sscentral.com has really in depth information on the physics of water guns, including a list of water gun related patents (http://www.sscentral.org/patents/ this one is I think the one that most closely resembles the technology and design of a CPS 2000, Figure 4-6 diagram the pressure bladder, Figure 7-9 the other mechanisms of the gun). Hopefully these provide enough information as to how these water guns work. 06:15, 18 July 2020 (UTC)
From Wikipedia (citing this page): "The CPS 2000 has been criticized for its low field life (how long it can last between refills) depleting its pressure chamber in only 1 second and only being able to fire 4 or 5 such shots before needing to be refilled, and the large number of pumps that it takes to fully pressurize (20-24 depending on version)."
I'm no expert when it comes to water guns, but shooting for just 1 second, with 20 pumps (!) required in between, does not sound fun. Maybe it was discontinued because they came up with more fun models?
--NeatNit (talk) 15:24, 18 July 2020 (UTC)
Good point, I'm trying to imagine kids really getting a kick out of pumping for 10 seconds, firing once, and having to pump again. Not fun. Combine that, reliability issues, and all around better models (from your link, iSoaker.com, lists lots of guns with better overall ratings), and I don't see the CPS 2000 lasting long in the marketplace. Plus it probably cost more, being bigger, which probably didn't help sales. 16:14, 18 July 2020 (UTC)

This should come standard with all spit valves. 21:36, 17 July 2020 (UTC)

Maybe I'm too knowledgeable about musical instruments, but this doesn't seem funny even as a satire. And there are lots of musician jokes about trombonists. Cellocgw (talk) 23:34, 17 July 2020 (UTC)

Randal probably doesn't play these instruments. I don't either and don't yet understand why the joke is painful to you. It would be good for us to learn to respect musicians like you better. Is it because it's disrespectful of an expensive loved instrument that requires great dedication to own? 23:58, 17 July 2020 (UTC)
No, we are good at disrespecting each other. It's just that the proposed "pump action" is nothing like how a 'bone works, or could work. Maybe I'm just being too pickyCellocgw (talk) 11:57, 18 July 2020 (UTC)
Seems to me that in this comic a super soaker was embedded within the trombone. Not at all related to the normal operation of a trombone, and not intended to be. --NeatNit (talk) 15:10, 18 July 2020 (UTC)
I think Randall just felt that the way a trombone slide goes back and forth reminded him the way a Super Soaker is pumped. It's just a silly joke, not intended as a serious comment on how trombones are operated. Barmar (talk) 17:08, 18 July 2020 (UTC)
I'm not a trombone player. I googled trombones and learned the trombone in the comic is being held wrongly, kinda upside down and like a water gun rather than an instrument, with the mouth piece very distant from the user's mouth. I play piano myself and don't usually see pianos disrespected, but they are very intricate machines involving great skill to make. It's notable a water gun is a much simpler machine than a trombone, which needs each part to be the perfect dimensions to make tuned notes. It looks like turning a trombone into a supersoaker might require hiding a reservoir in the flare, rigging the mouth piece with a one-way valve to collect air when "pumped", closing all the other valves and rigging a way to open the reservoir as a trigger. You would likely need to remove the reservoir to play the trombone again, and it may be a damaged from the pressure and airtight seal around the reservoir. Brass may also corrode from water. I'm wondering if it's exciting to see a trombone and then shocking and frustrating to immediately see it used so impossibly without any actual trombone experience demonstrated in the comic but I can't know. 18:25, 18 July 2020 (UTC)

I do play trombone and am impressed at that instrument is so accurately represented. A 'Trigger' on a trombone refers to the a valve, typically on an extra length of tubes called an F-attachment. this was both drawn correctly and used with good effect. Essaunders (talk) 11:51, 20 July 2020 (UTC)

Bagpipes. That's what I'm thinking next. Like this or this (possibly ), but wetter. 15:23, 20 July 2020 (UTC)

I was also thinking bagpipes. The tuba seems like a rare physics fail from Randall, the bell would disperse any amount of pressure and not be a very effective soaker, unless you think the whole gun is hidden inside, in which case, what's the point, really. 16:09, 20 July 2020 (UTC)