Sunday, October 30, 2016

Help me, Obi-Wan

I'm in the middle of filling those Holocron orders. I'm already sick of them...been sick of Holocrons for months now.

Oh, but while I was restocking parts at Adafruit (I'm dangerously low on some of the Holocron components already) I rediscovered a very cute little OGG-based sound board they have there. It's got flash built-in, is visible via USB as a standard mass storage device, and can be as easily triggered from a free microcomputer pin as it can be from buttons.

So I actually could make a Talking Holocron without that much more equipment. Since I've kind of overtasked the CPU of the current Holocircuit already, this would be a re-purpose of my previous Cree-based board (or the next generation Cree board...long discussion there about what is going to go on it, though.)

And it would also be a good excuse to test Cree lighting of a Holocron; now that I've incorporated the internal diffusor I previously thought was going to be too complicated to do...

Wednesday, October 26, 2016

We Have Liftoff

A dozen confirmed orders for Holocrons now. I'm now a full employee at the job I've been at for over a year, health bennies, company iPhone and all. And I've been playing Kerbal Space Program, which went on Steam sale the same day the 1.2 update was released.

On the latter, I've managed Kerbin orbit (using fairly minimal tech...mostly early solid-fuel boosters). And returned, which was trickier; I'd burned all my fuel reaching orbit but fortunately apokerb brushed the very fringes of atmosphere. After a few orbits my velocity had decayed enough for me to re-enter.

I think I've solved the majority of the mechanical problems in the Holocron. I do need to hop to it on a couple of software tweaks before I ship, however.

Oh, yeah. And work just sped up a little. We've got a couple of big orders and the parts for them just arrived today. As I'm fighting with a cold and sleeping 10 hours a night...but otherwise feel great, better than in months. Years even. I may have to park the car again and go back to walking to work...

Monday, October 24, 2016

Do I hafta draw youse a diagram?

Making a sketch really helps. If you can draw well enough (I can't) you can use it to communicate with a client or a co-worker.

When you are using it to figure out something, though, all it needs to be is clear enough so you can read it yourself.

I made a few dozen sketches of Holocron ideas before I finally found the idea I was able to take through Inkscape, laser, and assembly of a prototype:

I made hundreds of sketches, mostly by hand but to-scale with the aid of graph paper, on how the thing assembled. But technical work is not the only place where a sketch is nice to clarify your thoughts:

The above is actually the only plan I had to organize the big fight in the Abbington Estate a chapter or two back in my current fanfic. I can pretty much puzzle out what I meant now...I think the lower left is Zip up in Lara's room searching for her guns, center right is Teal'c hiding Alister and the injured Winston behind the Tiger painting in the Blake Room, with the Hall of Armor on the right fork of the passage, and of course at center is the Great Hall which serves as hub for every game that lets you explore the mansion, and the more spectacular moments of the fight in the (first) Tomb Raider movie.

And then there's this:

This is me trying to make any sort of sense of the Deep Time of the setting. The vertical axis more-or-less corresponds to time (logarithmically) and depth in the Earth (for some parts of the diagram). Essentially, the first Ancient culture was on Earth in the 2-200 MYA range, and among their other activities built Core Taps (essentially using a volcanic vent as a power source) -- many along the Ring of Fire.

Following the Wraith War (not to be confused with the Unknown Entity summoned up by Amanda's "Wraith Stone") a small number of Ancient survivors, now called Lanteans, come back to Earth. This is canonically at 10 KYA, which is problematic as the first Goa'uld (who later calls himself the Sun God, Ra) also canonically arrives on Earth about that time. One of them tinkers up the Asterion at Thera, built on top of the Core Tap there. If you look closely you might be able to make out a bull's head and a "clue" of thread in my scratchy diagram.

If I had the space, the diagram might have indicated things like the Elder Dryas, the first human migrations into the Americas, the Toba eruption, etc. There are a lot of odd things going on around that period! Canonically (according to the games this time), the surviving Lantean "triumvirate" on Earth breaks up, with Natla imprisoned in a stasis tube and Qualopec and Tihocan going off on solo careers as, eventually, mad old gods to early Central Americans and some sort of (possibly Mycenean) proto-greco-romans.

Roll forward to 3,000 BCE; Ra is overthrown, and the first historical Egyptian dynasties start up (no word on what the Assyrians or Sumerians thought about all this). Horus remains and is still wandering the Earth up through the Bronze Age collapse (witnessing the Thera eruption close-hand), at last getting stuck in a canopic jar sometime around the Amarna period of the Egyptian New Dynasty.

Some Lanteans may still be hanging around, whispering into Plato's ear (or perhaps Solon's). And to Iron Age "Celts," as well, giving rise to some of the Arthurian legend as well. Plus donating Excalibur, and continuing to use the Ring Transporter-like Travel Dias system established in various remote corners of the world (and possibly on others as well...wherever it is that some of the events of Tomb Raider: Underworld actually take place!) Others are off Earth, eventually either dying off or Ascending, but before that join for a time in a great league with the Asgard, the Nox, and the Furlings. The last have never been heard of since.

In 1945 the Trinity test frees Natla, who in due time seeks out and is successful in finding the three parts of the Atlantean Scion. Which is lost when another of the Ancient core taps blows up as did Thera, taking out Lost Island (which the games do not give a clear location for -- and as it is clearly either analog to or part of lost Atlantis, can be defensibly placed anywhere that amusingly mobile island-slash-continent has been placed by writers since Plato).

About this time the Stargate is being moved from Giza (having been uncovered in 1938), and Ernest Littlefield uses it in the post-war years. It is seen in a Federal storage facility outside of Washington in 1968, and finally fetches up at Cheyenne Mountain when Ernest's fiancé gets the program restarted. Of course we know what happens then!

And, no; not all of that is in the diagram. Mostly I have Lara, who has joined with unknown reason with psuedo-archaeologist Commander Newberry in his Landmaster-like "Ark III," (the diagram wrongly shows it with the funky tri-wheel arrangement) who may be stumbling on something Amanda left for them to find that may have something to do with the Ancient core taps that either Horus or Natla or the Asgard were investigating...

I think I've worked out my current plotting woes to the point where Amanda wrote a "Hello, Sweetie" message in some extremely obscure ancient tongue (possibly late-period Lantean) on the back of an artifact with equally obscure markings, which Newberry found and which attracted Lara to his dig in New Mexico. Amanda's message points towards Mount Shasta but also leads Lara into focus range of the Green Sun concentrator solar power plant -- which Natla Industries built, on properly previously leased by a wildcat drilling operation she blatantly named "Qualopec Oil Prospectors."

I did make one big mistake choosing Roswell as my starting point for the "Lara in the Midwest" chapters, though. White Sands, and most specifically the Trinity site, are a little too far away to properly explain whatever it was that Natla has been digging for in the Roswell area.

Saturday, October 22, 2016


I finished the Stolen B prototype today and opened up the thread at the RPF to start taking orders.

(Top image is the completed "Stolen B," including a prototype assembly of the final lighting diffusor, support structure, and circuit with USB jack. Bottom image is a mock-up using borrowed "Temple" shell and the lighting module from the "Stolen B" to show off the combination of "Guardian" diffusion and "Gallifrey" circuit layers.)

The above is also why I spent a few minutes today developing a BOM with parts numbers just so I could keep track of all the pieces properly. Here's the BOM for the design I've been showing off in earlier posts:

20.1 “Stolen A," assembled
0.1.31 “Stolen” shell set Top Side (3 pieces) USB Side Bottom
0.1.41 “Counselor” diffusion set Diffuse top Diffuse side (3 pieces) Diffuse side USB Diffuse bottom
0.1.51 “Circuit 2” set (6 pieces)
0.1.61 “Standard” diffusion cube set diffusion cube top diffusion cube side (4 pieces)
0.1.62 Support set support top support side (4 pieces)
0.1.71 “Revision 3” electronics package “Revision 2” neopixel board USB jack Standard LiPo Capsense wire Magnet (4 pieces)

Tomorrow I'll probably solder up another couple boards, and scrounge and adapt from my discards pile to complete the "Temple," "Stolen A," and "Imperial Archives" prototypes. I need two Holocron gifts so at least two of those are going away (I can't see those particular ones, as they don't quite meet my standards for shippable product.)

Yes...working at a company that makes precision audio equipment has tainted me. I think in terms of QA and Reliability Testing and BOMs and MAI's now. But I need to; despite my original intention of making the cheapest possible kit that was also as smooth and simple to assemble as I could make it, the realities of the core design elements of the "Stolen" fork has produced a design that has a lot of individual parts and requires a fair amount of finicky work to assemble.

Now all I need is to add a proper tracking system for revisions...

Sunday, October 16, 2016

Out with the old, on with the new...


Yesterday was productive. Checks have arrived, bounced back from sick (after getting even sicker, that is), I finally did the "Gallifrey" circuit design for the Holocron and drew up my big attempt at the "Guardian" diffusion layer. Old-school; worked with ink (and lots of opaque white) on a drafting board because working through a graphics program was constraining my choices in the wrong ways.

While I was shopping for a new technical pen to complete the above I got an idea how to make the Wraith Stone work.

I've been pondering for months various schemes of multiple castings or fills to get the green inclusions. Well, after seeing some "ebony" Rub n' buff at the art store, I finally made the paradigm shift to accept casting the whole thing in translucent green, painting out the rest of the model, and dealing with the less-than-perfect way paint will interact with the internal lighting.

And actually, if I go clear instead of translucent color (using the LEDs to provide the color) I may be able to omit a casting stage and use the printed model straight.

So, yeah, I'm all inspired on this one now. I also came around on the qualities of the raised edge; a hand-worked look and resulting variation of thickness is fine. So cut the basic form from MDF then build up the details in Apoxie Sculpt. It's going to be built at about 3-up, scanned, and then printed to the actual smaller scale so not that painful to get the details clean enough.

Thursday, October 13, 2016

Bass Canards

Passed the worst of it. Money came into my Paypal. Then my late paycheck arrived. I put in a full day at work. And I mailed off the latest set of M40 grenades. I even got a little fiddle practice in.

One of the reasons I've been behind on the fiddle practice is I've been using my breaks to tinker with an acoustic experiment. I bet I could get it declared a "20 percenter." Considering we do, well, acoustic design at work. Or rather, the company does. I reload coffee machines.

So what I built was an experimental Cajon. These are drums made in the form of (and historically, from) wooden boxes. Because of the nature of the sounding surface (or tapa), there are a variety of different sounds that one can get from one, including a reasonable approximation of the basic kick-tom-snare setup.

I was cutting from scrap wood, so I used slightly smaller and non-standard dimensions. But what I really wanted to explore was the idea of porting.

See, the box itself functions as a Helmholz Resonator. Not the perfect spherical one, however. Like a guitar body, the acoustics are a complex blend of the air mass inside the volume of the cavity communicating with the outside through the tone hole and modified by the flexible materials making up the body itself. This is even more complex in a cajon as one side of the box is the drum head itself -- which has specific resonance modes itself (multiple modes, in fact, with different combinations of strength of the various nodes excited depending on where the surface is struck).

According to a university acoustics lab experiment I read, even though the 0,0 node of the tapa is around 110 Hz, there exists a second peak of acoustic energy of the cavity. They were studying how this is modified by changing the diameter of the tone hole.

Well, I thought I'd see if I could emphasize low frequencies by using a cabinet design trick; by porting the hole. Adding a tube extension essentially lowers the emphasized frequency. This, at least, can be readily calculated. I didn't bother, as I was making this from available scrap. Instead I simply experimented.

Adding the port instantly cut much of the supporting resonance in the 200-400 hz range. Which is where the strongest most characteristic strike tone had been. It brought in a new peak of strongly boosted frequencies centered at about 50 Hz for the tube length shown above. The wadding (which I added to before closing the box) was designed and effectively did muffle most of the original "box" tone, leaving almost nothing but the "slap" of hand on wood and a deep powerful thump much like that you'd get from a good kick drum.

Unfortunately another part of the experiment was not as successful. It did not seem possible to selectively reduce the damping (and the effect of the porting) to allow richer, more tom-like tones in other strike zones. Nor was I entirely happy with the "slap" of the loose edge I designed for a snare-like effect (too woody, although it did have a good slap. I can put more sizzle in by adding guitar string under it, but I'm afraid this might be audible in the "kick" as well).

If and when I get back to this (I saved a few other pieces of scrap wood) the next experiment is going to be making a bongo-cajon but using partial baffles instead of airtight partitioning. I'll see how the two air volumes communicate and interact.

A little more on-line research and I found some good technical discussion at a Cajon builder's forum. And, yes, the porting trick is well known -- there's a pair intersection between Cajon builders and speaker builders. There's also a style of Cajon playing (and building) that aims for a close approximation of kick-and-snare (and, somehow, hat). 

But I find I side with the larger community in that I miss the "wooden" tone of the classical Cajon. That is, the 200-400 Hz range which my ported and damped experiment specifically reduced. However, based on a slightly better understanding of the underlying math (one day I'll get around to reading the rest of that book I have on musical acoustics) I've decided to pre-calculate the dimensions (particularly the critical sound hole dimension) of the planned Bongo Cajon.

Wednesday, October 12, 2016


Come out into the sunlight; it's just beyond the rain
come walk with me in daylight, and leave behind the pain
in the darkest of the night, there is still a light, it's coming with the day --
so leave behind your midnight; today's a brand-new day

A while ago I was working on a mock-up soundtrack to an imaginary B-movie. Above is meant as the English translation of the Cantonese lyrics of the obligatory up-beat canto-pop end titles track.

I've been pushing for a while to get the Holocrons ready to sell. One of the side effects was putting in shorter hours at work -- whilst simultaneously spending money on materials and other related Holocron costs. This caught up bad this week, leaving me too short to even get groceries.

I just caught a nasty bug (feels like one of those nasty three-day flu's that put you flat on your back for two of those days). Got bad enough I had to go home early today and may need to take tomorrow off as well. Which is really awful timing as we've got a couple big orders coming in at work and this is only my second week as full employee. Looks bad, is what I'm saying.

My paycheck didn't show up today, either. Only thing that did show up was a notice from my landlord that he's going to pop a surprise inspection on everyone tomorrow. Yeah, tomorrow -- with the place littered from trying to complete those dratted holocrons while starting a full-time job with a new level of responsibility and being too broke to afford even paper towels and when I'm so sick I can barely stand up (fat chance of doing some whirlwind cleaning tonight!)

So, yeah, this is a low. Even more irritating in that my newer and bigger paychecks start arriving on Friday, I'll be able to afford the car repairs by the weekend, I just rented out some audio gear for the equivalent of two weeks at my old pay rate, and I have over a dozen people posting the "Take my money, dammit" gif for completed holocrons (and doesn't hurt at all that I have already purchased the material for a half-dozen of them).

So I just need to get through a few more days...

Friday, October 7, 2016

I saw a pocket watch

That pretty much sums up the current direction of Fusion360.

Fusion is a great ap, and the new pricing schedule is actually affordable. But it does have it's peccadilloes. Chief among them being that it is being revised and revamped so frequently there are no current manuals or online help sources or other instructions that actually apply to the real program (they all reference buttons, functions, or entire modes of employ that got taken out several program versions ago).

This updating is, also, forced. On at least three occasions I've had a deadline -- I had to finish a model and I only had a few hours to do so -- but Fusion360 (unlike every other, intelligent, application) makes updates mandatory. Stop work and wait for their extremely slow server (two hours wait to download the latest update, not infrequently). No, you can't work in the background. No, you can't put it off. No, you can't even "fool" it by turning off wifi -- because Fusion360 is so damned cloud-minded all of your data files become inaccessible when you go offline. No matter where you try to force their storage.

So the latest update pushed through (along with the ominous warning that the next update will require an OS update, forcing me to use an OS with known and serious flaws), and it took even longer to start working. The side panel where all of my files are accessed stayed blank for a frighteningly long time, and when I hovered the mouse over it.......

....I got a watch face.

Anyone who knows anything about the Mac OS flees in terror at this point. You should NEVER be that deep into legacy cruft where you see the watch face. It basically means some programmer screwed up bad.

Monday, October 3, 2016

Holocron history

This prop took forever. But there is reason for it. Basically, it isn't "a" prop. There wasn't a straight-forward design process from a base idea through a directed iterative exploration.

I was handed a kit to assemble and paint. I'd just been introduced to laser cutting and engraving, though, and I thought I could pimp it up a little.

The experiments worked. Well enough I ended up documenting the project for Instructables. And that's where the trouble started.

Enough people at Instructables showed an interest that I made my files available. Since some of the parts weren't originally mine, I had to come up with designs for those, as well.

It was through Instructables that I was contacted by the master of a Jedi Temple, wanting a custom design made for his students. I agreed to work on it. Many emails and iterations and a full free kit shipped out no charge and I stopped being able to shake the feeling that he wasn't actually going to be good for the cost of the final kits. So I parted ways with that customer.

Since I now had a new and tested shell design I tried for a while to generate a new holocron based around it. But I didn't like (and still don't like) and of the results.

The holocron does not yet appear in any movie. It appears in some games and animations; one appearance being the best documented appearance I've been able to find. This natural goal was blocked, however, by the seeming impossibility of achieving it with the materials at hand. So I continued tinkering with other alternate designs, trying to fold in various motifs from the Star Wars universe.

It was at that juncture that I opened an interest thread at the Replica Props Forum. I got strong interest there, but still couldn't satisfy myself with the design.

Took a break to work on other projects. Did the Retro Raygun, some other things. My Croft necklace was also a hit, and I gave it away on long-term loan, which led me to starting the Wraith Stone project, and that looked to require some advanced electronics, so I picked up the holocron project again just to be able to work out the charge circuit and load sharing and surface-mount issues on a simpler board than what I intended for the Wraith Stone.

And when I returned to the holocron, what I had seen as an unsolvable problem turned out to be trivial. The critical insight might have been a function introduced on the new lasers just installed at TechShop; vector engraving. In any case, I immediately moved to front position a design much more closely based on that one animation.

It is just different enough from my first holocron, though, that the lighting didn't look right anymore. So back to some very basic development to rethink how the lighting circuit interacts.

And, of course, late in the day I realized there were possible ways to get it to look even more like my selected source. The very first holocron was a three-layer model; painted shell, solid diffusion layer, then the vector-cut "circuit" layer. I finally broke through this paradigm -- first through having to add a diffusor cube, then through realizing an inner "hypercube" might be an even closer match to what was seen on screen.

And that's where I am right now; cutting out yet more test pieces to see if this idea works out, while my growing list of confirmed customers are demanding I let them give me money...

Which is of course the absolutely perfect time for a major change at my day job.

Sunday, October 2, 2016

The Wierzbowski Aberration

Got back to the metal lathe yesterday. Took an hour just to find where they had the tooling this time and set up the lathe and dial caliper correctly. There's a lot of little steps even starting from a pre-made grenade body and it wiped out two days of shop time.

In a fit of optimism, though, I worked out how to harmonize the varied sources for the best approximation of what the alternate Pulse Rifle loads look like.

Here's the situation: in the James Cameron SF movie Aliens there appears an iconic weapon which is described on-screen as firing "10mm caseless armor-piercing" and "30mm grenades."

The latter is for all appearances used by Ellen Ripley near the climax, by Lieutenant Gorman in manual mode earlier, and is worn in bandoliers by many of the Colonial Marines. And it is a popular replica prop -- more specifically, it is a necessary prop for Colonial Marine cosplay. And I am one of very few people who have made a machined all-metal version available for sale.

James Cameron admits to Aliens being "his Vietnam movie." There are references in prop and costume design to the American equipment of that war. The grenade attachment itself has similarity to the army M203. Because of both this historical connection, assumed doctrinal/tactical considerations, and some scant evidence from the film, various third parties have assumed there are alternate loads to the red-capped round Ripley is seen loading in the elevator scene (and using against the Alien Queen).

These sources do not quite agree.

To harmonize, I've put the movie first. The only dialog mentions are "30mm grenade launcher" and "M40 grenades." The main leeway I have in the movie references is that the scenes are usually in dim, often colored, light (the Lieutenant Gorman/Private Vasquez scene is monotone red light), and the grenades are rarely in focus.

For instance, this image; the scene is not in white light but it is unlikely the safety cap on this particular grenade is red. Blue is just barely possible. It also appears to have only a single stripe but as the grenade is slightly out of focus there might be two. It also appears quite strongly to have a straight-sided, flat-topped cap, with no curve or taper.

This is a cropped and rotated screen-shot from the elevator scene; identified with high confidence as the standard M40 load.

Of course, it must be pointed out that there were a very small number of "hero" grenades carved from actual aluminium snap-caps by the movie's armorer, Simon Atherton. The majority of what appear in bandoliers on uniforms are likely to be wooden mock-ups painted silver. I have seen images of one such, but insufficient provenience to know if it is screen-used. In several screen-shots the grenades show visible wearing or flaking of the red paint.

In any case, the aggregate data from the film is that at least three cap colors appear, those grenades are otherwise identical, and no other shapes are seen. With the exception of Wierzbowski (I'll get to that).

Next comes organized third-party listings, such as graphics found from various sources (one is tentatively sourced as from the Aliens Legacy Forum. As an example of these secondary sources, The Aliens Technical Manual has sufficient errors right off the bat to remove it from any primacy against other aggregates of alternate designs. It also, perhaps fortunately, has few images and relies on verbal descriptions. There are, fortunately, no real disagreements in nomenclature between these, although no two sources give identical selections. It is in the shape and coloration that the major disagreements lie.

Below this are individual fan-made creations, as most of these lack identification labels and many are guided primarily by technological limitations, not by artistic considerations. They do, however, take primacy in clarifying the kinds of details that a physical prop shows off better than does a stylized graphic.

Lastly, there is reference to real-world analogs and presumptions about mechanism and doctrine. I would love, for instance, to argue from real-world human-machine interface that different loads should be different tactually; the soldier shouldn't have to guess in the dark, or in dim red light, which of several otherwise identically shaped loads she is reaching for. But there is a ready-made answer within the film itself; the film is about the hubris of technological fixes and the real-world failure of all that fancy gear when facing a less technologically sophisticated enemy who is smart, tough, and on their home ground.

So here's the harmonization:

M40: HEDP (high explosive dual purpose), this is an armor-piercing shaped charge with sufficient blast radius to be used in antipersonnel mode. It is dual-triggered, on firing, and manually by removing the safety cap and pressing on the button. It has a specific groove pattern, a "parting zone" that appears to be a crimp, an a red plastic safety cap with one white stripe. There is some argument that "HEDP" is meant to refer to the dual-role as a hand grenade and may have no specific armor-piercing qualities.

M38: HEAP. Presumed optimized towards armor penetration, this might actually be a sabot instead of a shaped charge. It is identical in body pattern; it may be a poor choice for load selection in the dark, but might be justified as interacting with the Pulse Rifle's internal mechanisms. Going by the Newt close-up, this has the same plastic safety cap in green.

Here's where things get interesting. The graphic I found at Aliens Legacy gives all the rounds as having tapered caps. This clearly disagrees with the film. The Aliens Technical Manual only shows the M40 cap, and gives it as tapered. The tendency in other secondary sources is that the M40 cap has straight sides, the M38 tapered, and the M51A has a rounded top to the cap. The tendency is also in secondary sources to show all rounds as having double stripes. Most of this is clearly contradicted by the film. However; almost all secondary sources agree that the first three of the grenade family have an identical groove pattern.

M51A: Bounding anti-personnel. This is a clear analogue of the real-world "Bounding Betty" mine. It seems odd to put in a grenade, but this is consistent enough across third-party sources and fits so well within the milieu of the film we just have to assume some kind of auto-righting mechanism. Same groove pattern, straight-sided blue cap with dome; of the third-party sources that give each of the top three a different safety cap shape, the consistency is that M40 is square, M38 is tapered, and M51A is straight-sided with a rounded top. It isn't required that under every safety cap is an identical button, but given the auto-righting justification above only a sabot round makes absolutely no sense in that kind of dual role. (There are other button inconsistencies later, so even this isn't beyond possibility; perhaps they simply used the same shell with different loads.)

(A different problem with real-world analogs has to do with the specific blue. They appear to be a light blue, far too similar to the distinct "training round" blue standardized in the US Army. I guess we must assume that semiotic standard has changed by the period of the film).

There's a last interesting possibility; the clearly, tactilely distinct caps could be a late innovation. Given the murk of the film I don't think there is any scene showing blue-caps that can't be justified as having domed tops that just aren't properly visible in that shot. The same justification could be used to assume tapered green caps; this would make the "Newt" grenade an aberration explained as old stock from before the change-over (since they were pulling every bit of salvage and hidden-in-pockets ammo for their defense). It is also plausible they were all tapered at some point and the manuals are using outdated images.

For Aliens cosplay, however, straight-side caps is consistent. They are also easy to make. So this is why I say my props above are almost correct; the only change I would make it to add a slight dome to the blue cap.

M108: Canister. Presumably the Sulaco crowd didn't pack any, because they'd certainly have come in handy. The third-party sources are remarkably consistent in showing an identical groove pattern to the "big three," no safety cap, and a broad flat nose with some sort of black plastic disk. This is clearly explainable as some sort of disintegrating cover over the payload. A manual fire button also does not seem to make sense. There is some argument that what gets ejected would be different; does the body of the round fly downrange then a secondary charge kicks out the shot? In any case, this is a straight-forward build. (But also superfluous for straight-up Sulaco marines cosplay).

M60: WP/incendiary. The sources are a little unclear as to the exact weapons action here but white phosphorus is very, very Vietnam. The manual states white markings, all other sources give yellow. The sources (all sources are third-party, with one possible exception to be discussed) seem to converge on it having no safety cap, and a domed top with a wide, flat button. This is quite consistent with secondary employment as a hand grenade. The major disagreement in the sources is whether it shares a groove pattern with the "big three," or whether it has a unique groove pattern and a yellow paint band on the lower third.

And here's the Wierzbowski problem. In some scenes this one character appears to have a grenade with a yellow cap. And it appears to be the same square safety cap as the M40. So here's my explanation; Wierzbowski made a field modification. As issued, the M60 has a yellow plastic ring around a metal button (similar to that of the M40 but wider and less tall). Either Wierzbowski didn't trust this, or the ring functions as a safety and is considered difficult to wrestle with in the field; either way, he has replaced it with a discarded M40 safety cap and dipped it in the same yellow paint other marines have been using to paint slogans on their armor and helmets.

The other issue with the M60 is harder to reconcile. I'd argue against having paint on the sides as that could foul the weapon, but the only third-party depictions of the smoke grenade also show color bands on the grenade body. The tie-breaker has to be the movie; a yellow band should probably have been as visible as the yellow cap, thus, we have to assume this has the same standard body as the M40.

M61A: Smoke. This is the only smoke listed in any of the secondary sources, and in that source is shares a groove and banding pattern with the CS grenade. Doctrinal similarities seem to call for a variety of colors, and those would you would think have different nomenclatures as well, but none of that is provided. It has no safety cap, and a similar rounded top and broad flat button as the M60, lacking the color ring on the top (what I am assuming is a plastic ring that may function as a safety clip). The groove pattern is definitely different from the M40 standard, consisting of two wider grooves creating a defined band which is colored with (one presumes) the color of the smoke. The button may also share the same color.

M67A: CS. This is an odd one; it either shares a banding pattern with the M61A or has the same basic groove pattern as the M40, however, the majority of sources are consistent in giving it two narrow red stripes which may or may not be in shallow grooves. It has a gently domed top, no safety cap, and also lacks a button. For this, I simply have to wave hands in the direction of assumed Colonial Marines doctrine. Since they aren't visibly carrying protective masks, perhaps it was determined that this payload was unsafe to deploy at throwing-arm range.

M72A1: Starshell. The depictions are consistent; this lacks most of the standard groove pattern but has longitudinal grooves running down the length of the body. It like many of the alternate rounds has a domed top and no safety cap. It also has a button. The conservative answer here is that this is a self-righting shell, like the M51A, and thus can be hand activated as well as fired horizontally (instead of requiring the operator to point their weapon at the sky). Other possible answers are that the button is non-functional, or only looks like a button. Lastly, the technical manual claims it is marked with an embossed "S." This is not entirely inconsistent with the nature of the graphic depictions.

M230: Baton round. I didn't notice any depictions on my earlier searches. This has certain practical difficulties, depending on exactly what parts of the round can be and are extracted from the shotgun-like action of the weapon (hurling a metal case down-range would rather contradict the intent of a baton round).


Oddly enough, the general answer to the question of making alternate loads available for cosplay is a simple one; paint the caps different colors. This even applies to the Wierzbowski; cosplayers are more likely to want to mimic his documented field modification than the hypothesized standard-issue version.

The majority of the alternates lack safety caps, which is mostly to the good, but they also tend towards gently domed tops -- which are hard to machine. They also tend to buttons, which are a known labor issue (as a reminder, my last machining trip took over four hours just to set three buttons). About half of them also involve body colors, which could be an issue (especially if chambering is intended).

Lastly, they just aren't that interesting. Only the star shell is significantly different-looking and requires enough new machining tricks to be really tempting.