Category: Bots

Any posts about the robots!

Your Waifu is Back…. and Still Trash! Rebooting the Dumpster Miku: The Designing

chorl
what a title. we live in such a society

Poor Dumpsterbot. After the initial build in 2019, it might be the highest mileage robot I’ve ever built – literally, not figuratively. It’s driven through probably five conventions at this point, to great fanfare…but the shitty Miku Blue spraypaint I put over the shitty gold spraypaint NHRL put over the original green paint just flaked off in large pieces over time.

It was already showing its cracks in Houston in 2022. I decided to retire it for Momocon 2023 because it was just too decrepit to be funny:

There was like… no more miku left because all the stickers gradually fell off. And so, YWIT just sort of lived on that workbench being shuffled around until I tossed it in *somewhere* to move to the New Robot Trap House. It then lived on a hangar shelf for the better part of the year as I attended to the everything else that needed me screaming and running in a circle.

But with the NRTH having reached some kind of ignition/criticality state earlier this year as I managed to birth Stance Stance Revolution, I decided to revive it for Momocon 2024. Well that came and went…

Some time in early June, I pulled it out and decided to see if I could get a local auto body place to strip the paint off and start over. What I learned during this process is that America has pretty much decided it’s done making or building anything, for a variety of reasons.

I mentally had a “Probably around $250” estimate for stripping or at minimum roughing up the original coat, then blasting it in obnoxious candy-Miku-Blue. I had a bunch of places, even more Bubba-n’-Sons looking corner auto shops, decline this (admittedly rather small) work and give me farfetched tales of costing hundreds of dollars to boot up their sandblaster. It might just be the area and I didn’t go exploring far enough out or deep enough into the hood, but all of these shops seem to be hooked on big-dollar insurance claim jobs.

I get it, labor and input costs are higher than ever, making fewer and fewer products worthwhile to repair in our society. Just throw it away and make it China’s problem. That’ll never come back to bite us in the ass or anything, right? But then I got a reference to a nice hole-in-the-warehouse shop whose owner would allegedly paint anything.

This was the state I delivered YWIT’s emptied shell to him, and just two days later, for only $150, I received it back like so!

Fuck it, I just left the whole $200 there as a tip for not giving me a runaround fairy tale about the role of the President in deciding the inflation rate. Absolutely galactic, brilliant glossy single-stage Miku Blue!

So much of my value add to both my own projects as well as organizations I am a part of is simply knowing where to get things made/done. This is a critical part of keeping costs and lead times (and frustration) down. I had a bunch of favorite service providers back up north, but have been slacking establishing those same relationships here because the industry is a lot more dispersed here, and I have mostly been a fully DIY, self-contained universe for the past handful of years.

Plus, it’s not like this was just some old dude in the back of a shed – they had some very good looking work going on, and I wouldn’t hesitate to bring Vantruck here for some severe “paint correction” work (a.k.a please rescue my orange peel and runs because it’s not worth putting anime girl wraps on)

Okay…. with the Dumpsty chassis looking THIS GOOD I had no choice but to press onwards and revive it!

The Wishlist for a New Miku Dumpster

As usual, the inspiration for this whole affair started with a random motor.

Well, back up a bit. The random motor bit is nice and all, but I did have a list of wishes for YWIT ever since I fired it up the first time.

  • Drivetrain-wise, it used four Pololu 25mm gearmotors that I had left over from who knows whatever robot years ago. I made the choice back then because I was actually targeting it for the 12lb weight class. The dumpster alone was about 8 pounds, so I was basically making a beetleweight with a big hat. This meant the bot was limited to around a slow walking pace, turning on concrete/smooth indoor floors was a challenge, and I was losing a motor per two events or so (three in total) just from wearing them out under heavy loads! Like I said, highest mileage robot.
  • It likewise had the issue of very low ground clearance because of the small size of the motors and small wheels. It had to be helped over most obstacles including cable protectors and any higher than about 1/4″ gaps in sidewalks. So really, it was operated in open areas with low foot traffic indoors (like at Comicpalooza) or in limited smooth patches outside in full c l o u d z mode. Commuting with it was quite difficult.
  • The battery cavity was small, in order to work with packs I already owned at the time, 4S 1.8Ah ones. So I carried up to 2 or 3 spare batteries. Each one was good for about a half hour at most before it got too sluggish. I lugged around a shoulder bag full of mixed lithium batteries and pointy hand tools all the time – how positively quaint.
  • As for the smoke generators themselves, I was donated two CosClouds early prototypes by Spoon Makes which I basically drove into the ground and put through immense abuse… and they took it! Only real downside was that their capacity was limited… because they’re supposed to be worn and hidden on costumes, whereas I am basically putting wheels on a fog machine. This meant I stopped to refill it every 15 minutes or so.

So basically, I went into the new build with the following points of functionality in mind:

  • I’m going to size the drive motors for continuous operation with no thought given to a weight class, and likewise, the power parts will grow to accommodate it.
    • That said, check the giant bag of Banebots 1.625″ wheels in the photo. I wanted to keep using these wheels because I actually have about twice as many as shown in that bag (this has gotten out of hand… now there are two of them) and really only wore out a few.
  • In retaining the wheels, I’ll need to drop the axle height relative to the drive motors (a portal gear system, in a way). This will necessitate a little “lump” by the wheel that’s still relatively low clearance, but as long as the wheels are what roll over the skinny extension cord first and not the body plowing into it, we’re good.
  • The wiring for the thing will be actually planned, with places to mount things properly. The existing wiring was very “thrown in there” and I lost at least one of the CosClouds units once just by breaking the ass of it off at the connector interface, and the battery probably landed on it or something.
    • Specifically, I’ll spec a larger battery encasement than I’ll probably run – say, for a 3300 or even bigger battery, if I choose to do so in the future. Otherwise, I can still just run the packs I own.
  • I’m going to be adventurous and explore the drone enthusiast vaping rig ecosystem myself and see if I can put some heavier duty parts on it. The current generation CosCloud system looks great, but I’m seeking a lower profile blob or brick form factor. Some initial eyeballing at local vape shops (literal vape shops…. not my kind of meme vape shop) turned up some candidates I’ll go revisit.

Other than keeping these guidelines in mind, I was just out to build a damn robot again, man. Remember the quote from the end of Operation IDIocracy 1.0:

It’s time to just shit out some beetleweights. 

- me, at some point recently

Alright, so about those motors.

I have a lot of motors. Not only from my own collection, but back in 2021, I also “inherited” in a way much of the EE lab and machine shop stash of the late Dale Heatherington, my O.G. robot mentor.

I helped the family clean up the workspaces and the house, and identify things of historical or cultural value. Many of those items, such as early hand-wired PCB prototypes of Hayes Microcomputer products, went to the Computer Museum of America, a local institution. And some of them I personally delivered to the Smithsonian on a commissioned run to Washington, D.C. last year. There was absolutely no way you could convince me to trust UPS with any of it.

There were also plenty of things of no historical or cultural value. One guess as to what I ended up with! This photo is probably 2/3rds of the motors I have, by number, but less than 10% by mass. To the left is another 7 foot tall rack that’s full of….. much larger motors. Way too big for this project.

(BTW, organizing The Stash like this took weeks. I was basically combining three standards – mine, Dale’s, and my old chaotic ADHD pile. 97% of the house-related efforts of the past year have just been making my shop. I pretty much otherwise only mow the lawn…)

I dug around for a few choice candidates. I was looking either for two motors that were powerful enough on their own to be plausible, or four smaller ones that were still larger than the Pololu motors. Dale’s collection is a lot more vintage than mine (literally… than me in general) and contained quite a few old hobby robot legends like Pittman, Globe, Buehler, Maxon, Escap, etc.

Names that middle/high school me would have coveted from the AllElectronics (RIP) or MECI (RIP) catalog. Now all superceded by shitty Chinese outrunners. shakes cane and creaks

The motor on the silver bracket in the center of this lineup ended up being the most interesting. It was some kind of servomotor used for motion control, as it had a very fine encoder on the back and a MXL timing pulley already attached to the output. Dale had helpfully scribbled using a marker the Important Motor Numbers: 172 RPM/v, and 5.2 ohms line to line.

That’s really all I needed to know, because combined with the sheer size of the thing, I knew I could use two of them only and drive it on 6S (22V). And then it’ll still be spinning slow enough (3900 RPM or so), that I’d only need a roughly 2.5:1 or so reduction to achieve a healthy 7mph speed. That’s reasonable jog territory, and can be accomplished in one gear or belt stage.

They were torque beasts – 172 RPM/v becomes a (theoretical) 7.8 oz-in/A torque. I measured the stall current to verify the resistance, and so concluded the system should be capable of around 100oz-force of push per side through that 2.5:1 gearing with the 1.625″ wheels.

Probably not something I’d choose for a combat drivetrain these days, but this drivetrain will be incredibly smooth and quiet!

(I am so, so not sorry to anyone who has to deal with this private electronics surplus store in my basement if I accidentally and irreversibly drive Mikuvan off the cliff instead of perilously close to it)

With my Random Motor Inspiration, it was time to start throwing down lines.

A few critical elements define the initial sketch. First, the overall length was constrained by the fact that I have to lower this thing into the Dumpsty chassis from the top. The wheelbase was fixed as well, given the position of the existing wheels. Next, I set the ground clearance I wanted, referenced from the bottom of the chassis.

That really meant this drive pod housing could be one shape. Man, it’s nice working within existing systems, even if you’re the utter fuckup that designed the existing system in the first place! I keep coming back to the thing I told the former 2.00Gokart students – some times you have to design and make the first one shittily to know what to design and make better next time.

Even at this early stage, I was already looking at a portal gear drive from the wheel axis up to the drive pod body, where the two wheels per side will be linked by a timing belt linked to the intermediate gears. The motor is probably sitting at one end and driving another timing belt to reach down to the intermediate gear shaft.

I decided to play around a bit with the whole “smooth and quiet” part and generate myself some helical gears. I haven’t used this feature of Autodesk Inventor in forever. The helical gears should hopefully mitigate some of the inevitable whining and whirring of 3D printed gearboxes.

Inventor makes the helical gears using an extrude-along-a-helical path where the helix is already calculated for you, based on your inputs to the Design Accelerator tool. I was planning on just whipping these gears out using nylon filament, so I was after their basic geometry, to which I can append other features.

I do a thing where I pre-emptively shrink the gear tooth profile inwards using said Design Accelerator tool, because 3D prints almost always end a bit fat – with extra material, or simply surface irregularities acting like it. In the tool, you can enter a total backlash (slop) desired and center distance compensation, which effectively makes the tooth skinnier in the model.

I extruded the original sketch and hollowed it out to make a basic gearbox casing. Bearings are specified based on what I already own – drive axles are type 6801 12mm bearings, and the intermediate shafts are MR148 8mm thin-section bearings. I added a “registration feature” to the bottom of the drive pod so it can align with the existing cutouts I made to the bottom plate of the chassis.

All of these dimensions were kind of in flux and were changing as I made new geometry. For instance, the casing had to get a lot deeper once I added…

…the timing pulley to the intermediate gear. I simply stole a model off SDP-SI, cut off everything but the tooth profile (performing my pre-emptive profile shrink too), and imported/inserted a body into the gear part, then bridged the two to fuse the bodies. This robot is definitely an act of 3D piracy across multiple vendors.

I’m not sorry.

The belt in question is the 3mm HTD profile that I mentioned is my go-to for manufacturing on my tiny nozzle equipped Ender 3. I elected to use a 9mm wide belt to handle the torque of the drive motors.

The belt length I needed was discovered by a bit of back-and-forth using SDP-SI’s Center Distance modeling tool. I started with the dimensions I was hoping for, and it tells me how wrong I am. I then feed its recommendations back into the CAD model and see if I can make it work. Usually, the answer is “Yeah, fine, you’re right. Have it your way” and I then have my retribution by buying the timing belt from a random Amazon store instead of the company.

A 105mm center distance with 20-tooth pulleys actually works quite well, so excuse the glibness. I added a very tiny amount of overhead (the 0.05mm extra) as a hedge against ever needing a tensioner.

Here’s one of the intermediate drive gear + pulley combos. It will be riding on a live 8mm shaft, so the bore will be sized for a moderate press fit. I’m simply going to cross-pin the gear to the shaft to keep it in place.

Continuing on, I made placeholder parts for the lid of the gearbox and the input and output shafts. The same 1/2″ hex shafts with retaining rings to hold the wheels will be used.

After importing the wheels, I was able to size the shaft length and snap ring groove offset positions much better.

At this point, I dragged everything into the main assembly for a visual test fit. I like it so far! This test fit allows me to determine a way to stand it off from the inner side walls and also where to put mounting holes. A little bit of dimensional tuning later, and now it’s time to figure out where to put the motors.

I might have already intimated that these motors are quite large for what they’re going to be mounted in. At least, this drivetrain is going to take up far more space than the old Pololu gearmotors! I had to keep in mind where the lid servo (remaining unchanged) was going to swing, as well as make sure I leave space for the future electronics package and the still yet to be fathomed vape cannon.

I decided to keep the motors in the front for center of gravity reasons. I’d rather this thing attack obstacles on the ground with the heavier end instead of potentially kicking back and tipping over backwards.

To mount these things, I decided on simply ring clamping them, versus doing a face mount using screws. It kept the gearbox housing as a single 2.5D shape with a flat face to put down on the build plate, and it was deep enough (35mm) to give plenty of circular area to hug the motor.

Notice the small design change to the center rib with the two holes in bosses on the ends. I changed it from a straight-across rib to a curved one. The curve acts like those fences made of zig-zagged pieces of wood and adds a little more rigidity to the result, plus helps disperse stresses from the print process and adds some stability during it too.

The motor will sit like so, in the loving embrace of a circle of fiber-filled nylon.

Clamping ears for the motor are now modeled as well.

I change my view preference depending on the time of day – at night, I’ve long preferred this quasi-wireframe mode with the softly hidden edges. It lets me “select everything” as I need, is not as irritating to look at as a straight wireframe, and also works better with the generally darker night skins of the software. It’s also very aEsThETiC.

One random trick I’m adding, largely because I am non-committal as hell about the eventual belt drive ratio, is a way to easily adjust the motor up and down a bit and hence the tension of the belt. This is accomplished using a split clamping sleeve that has an offset hole in it. In this case, the offset is 1.5 mm, enough to let me swivel the motor around a central axis a total of 3mm. It should be able to accommodate any random pulley setup I can think of!

All I’d need to do is partially tighten everything with the motor belt installed, then just flick the lever, rotating the motor around until the belt is tensioned.

I’ve moved on to sizing the input timing belt and pulley. Back to the Center Distance tool we go!

A small amount of dimensional massaging (adjusting the vertical position of the motor axis using the big clamp feature sketch) and I have a pretty good solution. This is actually a 2.66:1 ratio, which is a fine conservative increase from the 2.5:1 I had in mind. With the motor in a center position in its tensioning ring, I can use a very common 60-tooth timing belt.

Here’s a full view of the drive pod from the “outside” of the bot with the casings hidden. This was pretty much ready for showtime.

The pod will be mounted on each side using four holes. Two will be in the main gearbox casing, and two will be on a Big Combo Spacer.

So… the part I care about is basically done. I generated an in-assembly mirrored model to check everything out from a space claiming perspective.

After test-printing a gearbox casing, I went back to make a design change to require no support lattices. It was kind of annoying picking the support droppings out of everything, when really only one area (the motor clamp ears) needed it. This version uses a single clamp bolt and some crafty angles that I just tell the slicer software to shut up and deal with.

In another sign of noncommitment, I added a series of breadboard standoffs (the four vertical pillars here) each of which contains three holes spaced 0.5″ apart, making for a small 3×4 grid of holes. This means…

…I can add WHATEVER BATTERY AND ELECTRONICS TRAY I WANT. At any point I want. Like this battery bucket, which is sized for a 2500-2600mAh 6S lithium pack. I already own a 6S 2200, which will be a bit loose in here, but whatever. That’s what not falling down the stairs is for (….oops)

On the other side, another Metabracket supports the RageBridge2 I used for the drive controller, as well as the…. I’m sorry, did I say earlier that all of the wiring should be planned and the electronics should have homes and stuff?

Well, consider this some kind of cash-under-the-table flophouse or a “free rent with terms and condtiions”. I just made a bunch of slots and holes to run zip ties through. The vape cannon power supply, Pololu R/C relay, receiver, BEC…. they’ll sure mounted to something alright.

This concludes the design of the important bit of the new Dumpster Miku! Next up, the fun that is fabricating and assembling it. You’d notice a scarcity of vape cannon information, which is forthcoming – at this point, I was still unsure what form it would take.

Building the Stance Stance Revolution 2

chorl

It’s about two weeks before Motorama 2024! Plenty of time to finish a robot and test it and get to know it…. right!? Theoretically, most of this bot could just appear overnight after a bit of press play and walk away. We’ll see that it wasn’t THAT easy, but it was still a super streamlined build, with machined parts being made while the 3D printables were materializing.

As alluded to in the previous post, my Ender 3 has been the workhorse for making small power transmission parts. I don’t think I’ve bought a gear or pulley in a long time, except things like extruded pinion wire I used on Susquehanna Boxcar. I equipped this Ender 3 V2, a little outdated these days but perfectly functional and smooth, with a 0.2mm nozzle so it can really hit all of the smaller details in gears down to about 32 pitch (0.8 module) or timing belt pulleys down to roughly the 3mm HTD pitch.

I’ve tried things as small as 2mm GT and MXL, but they’re not that clean. So, much of my “all in house” mechanical work focuses on the larger sizes.

This build was an opportunity to bring the Markfrogs back online after sitting decrepitly in a corner forever after the big move. This thing here is basically a classic car – it’s technically a “Mark 1.75”, being in the chassis of a Markforged Mark One but the extruders and controller of a Mark Two.

It was provided to me as the original Overhaul 2 sponsorship package (that’s 2016 if you’re keeping track) and has produced basically all the bracketry for it and Overhaul 3!

So let’s just stuff some carbon fiber in it and GO! The Eiger slicer software has evolved a lot since I last used it a bunch, so the UI took some getting used to. I was able to use the 3D representation of the fiber laying to fiddle some dimensions on this weapon motor mount. Basically I wanted more perimeter loops of carbon fiber, so I had to adjust the wall thickness of the mounting hole area to let it run some lines through.

Here’s a visual test fit of the weapon motor bracket and the drive gears. Somehow, an almost 9 year old machine that’s been sitting mostly dormant the last handful of years and got thrown in a van and then into a corner just wakes up and pounds out a carbon fiber inlaid part.

While making very crunchy bearing sounds, too – those belt tensioners are facing a desperate deferred maintenance condition that I really need to address!

Most of my nylon filament was in abject condition, of course, having picked up a ton of moisture from sitting around. Even a closed container isn’t that weathertight in the long run! So I had to bake my nylon spools (and threw the dessicant packs in for kicks too, to refresh them). I ended remembered too late that gas ovens produce water vapor as a primary emission component and ended up simply steaming my nylon for over 24 hours.

So… uhh, oops. Slight delay in the build as I hunted down a small electric convection oven on Facebook Marketplace to use as my dedicated filament roaster (and future epoxy setter, urethane curer, and so on). Obviously this meant I had to roast each spool for about the same time to get them even remotely printable again…

My supplemental order of Aliexpress worm gears also showed up around this time. The bot will ultimately use 20 tooth gears (these are 30 tooth in the image) but things were cheap enough that I just ordered a small pile. There’s a nice drawer labeled “Gears and Gear Accessories” they can live in!

I designed a few different wheels for the bot as well and tried each design out. They differ in weight as well as philosophical approach. I started with a basic “solid” wheel that could be printed using a sparser infill. This lets the wheel act a bit as a damage sponge as the infill can crush in response to being hit. I also made a basic spoked wheel which weighs a bit less. It also did take less time to print, so I decided to press on with that design for now.

At the end of the week, here’s a pile of completed parts. I decided the weird t-nut pinion gear was not going to stay in the final bot before I ship out. It was definitely too flexible. It’ll do for some basic testing, though.

I merely made a revision to the gear design which used a large hollow bore I could press an aluminum round into and drill and tap like a normal human.

The next parts to arrive were the weapon discs from SendCutSend. I went ahead and ordered a pile of them as well. 10, to be precise. I’m hoping this bot design stays around for a bit or else I’ll have some interesting yard Frisbees.

The long print job was the unibody, which took something like 28 hours on the Mark 1.75. It was the machine I trusted to just blast through the job without poking it or adjusting it!

The completed chassis. It’s not made of Onyx – I can’t afford that stuff any more, so it’s instead just generic Microcenter carbon fiber filled whatever. Definitely smells like nylon, but it makes a substantially different sound when you tap on it and is slightly more flexible. Somehow, despite me putting the most shit-tier mystery filament into it, the print quality was impeccable.

(By the way – that stuff comes pre-wetted. I don’t know if they extrude and reel it up in a tropical rainforest or what, but 10+ hours of 90 celsius or more drying is needed before even TRYING. If you’re not warping the spool, it ain’t hot enough!)

The next op was to make the disk hubs. These are just made of small chunks of 2″ round aluminum. I had remnants of a thick-walled tube that could be quickly turned down and bored out to size.

In lieu of a mill, because over the winter I sold the Benchmaster, Master of Benches and HAVEN’T BOUGHT ANOTHER MILL YET I made several drilling jigs for the parts I’d typically use a mill for. These were dimensionally tuned to tightly grab or press onto the part. I use them only for spot drilling holes, then press them back off and finish the drilling operation without them.

I didn’t want to give up the Benchmaster, Master of Benches, but I cared more about having a quill and having DROs and longer travels than its historical value. So after putting it up for sale at an obnoxious price to deter most people, I got a message from a guy who has a small collection of antique machines who was interested in restoring it as part of his vintage shop. Naturally the sale value was much more reasonable than the obnoxious go-away price. Not trying to turn a profit on it so much as maybe pick up some tooling for the Future Robot Trap Mill.

I went ahead and made three hubs, two for immediate use and one for if somehow an opponent reaches that deep into the bot. By that point I’m guessing the rest of it is hosed already, but…. good to have a backup nonetheless.

The disks interface to the hub using these four dowel pins pressed into the flange.

For the weapon shaft mounting blocks, I did the same get-jiggy-with-it operation on a chunk of 1″ wide, 1/2″ thick aluminum bar. This jig manufactures two blocks. It contains the drilling pattern as well as two marks for where to saw it in half.

I made the driveshafts as planned – just turning a shoulder, snap ring groove, and partial shoulder onto a 3/8″ aluminum hex bar. The small shoulder is for the bottom shaft bearing, and the big bearing sits on the half-10mm-half-hex portion. The gears were drilled out for the 10mm bore, and I added two little dimples to let their set screws get a more positive grip.

I think if I were to do this over again, I’d just replace the screws entirely with a single 2-3mm roll pin or something and have less things that can wiggle loose.

It’s starting to look like some kind of weird clockwork mechanism now. The future double-ended motor shaft is made from lengths of 304 stainless steel which can be picked up in 3mm undersize precision ground fit. No need for the case-hardened linear bearing grade stuff here since the forces are relatively low!

The shafts are cut to slightly shorter than the total length between the chassis pockets that house its support bearings. Then I just move the worm gears to where I want them and marked locations to put small flats (using a Dremel) so the set screw on each can grip. This whole assembly was already so smooth that the gears could somehow backdrive if I turned them with some effort!

Motors prepped and being installed with the new shafts. This just involved pressing their stock ones out and maneuvering the new one in place.

The next item to arrive was the side plates from CNC Madness. This operation is hands down the cheapest way to get composite flat parts made quickly right now, and I leveraged their 3mm and 2mm carbon fiber for the weapon uprights. This took just under a week from when I hit the Order button.

All I needed to do was add the countersink holes and the bot was suddenly together! I chose to use large #10 thread-forming screws for plastic (“Plastites”, if you will) instead of heat-set or coarse tapping inserts. Keeps the weight down and gets the point across for the strength of the material I’m fastening into!

The wheels are retained by these wide-face E-clips. No screws here, everything is made of laziness.

After the worm gears were firmly secured by the side plates and lubed up, I found out they in fact could backdrive quite readily. I attribute this to floating the shafts on ball bearings so neither radial nor thrust force caused a bunch of extra friction!

Weapon assemblies undergoing final assembly! The ring gear is attached to the hub using eight countersunk screws, with the aluminum hub flange being threaded to accommodate. Overall, it’s quite a compact package. As I said before, the only thing I’d like to change here is backing down from the gigantic 6200 type bearings I already owned. At least this thing will never fail due to that!

The bot’s entered the “difficult to look at from any angle” stage of assembly here, and was mechanically completed the weekend before I left for Motorama.

The electronics of this thing were done dirty. The 660mAh 4S battery just sits in the cavity in the center designed for its size range and the bottom plate holds it all in. The ESCs are leftover SimonK AfroESC 12 amp units from forever ago, when I bought a few dozen and have slowly since used or given them away in various ways.

The receiver is just a shucked Hobbyking TR6Av2 (or FlySky FSR6B) receiver that I’ve used for… oh, I’m not sure, 13-14 years now? They’re somehow still around and being sold, and my transmitters still work! Odd to put it like that, because it would be equivalent to using a 1992 model radio in 2006 when I first could afford/switched to then-new Spektrum 2.4Ghz tech.

The power switch is a random Fingertech switch I’ve had forever. Everything’s just hot glued in place and point-to-point wired. It’ll basically be impossible to service!

As a last touch and nod to its cultural inspiration, I made some cringy heart rims for Stance Stance. I ended up only bringing these and the 5-spoke wheels to Motorama for weight issues.

Check out the finished product! I’m very proud of how this bot turned out. It looks very sharp and clean, in my opinion. I decided to not paint it in its usual magenta and blue for Motorama since I didn’t want to take everything again, but will do so for future events!

Here’s a video of the worm gear drive! At this point, the left side still had a bit of a sticky spot which I never quite figured out, but it went away with a lot of driving.

The handle is extremely linear and predictable, since the worm gears basically act as an amplifier for motor drag and braking. I was definitely satisfied with how it drove, but only the event can show how durable and reliable it is.

Why was I such a stickler for weight? Because this is what the thing ended up at~ That’s 0.4 ounces under the limit. It’s just so full of gear. Figurative AND literally! I’m actually not sure where it can get any lighter. Perhaps the weapon hub bearings will be a good start, because it’s very much two hard shells and a very creamy, soft center. I’d like to try and transfer some weight into protecting the front, rear, and bottom some more.

The rest of the week before I left for Motorama was spent putting some more of the spare parts together and some test driving dancing in the driveway. Altogether, Stance Stance Revolution 2 was a pretty clean and enjoyable build that needed some design thought to execute, but it wasn’t like I had to devote all four of my remaining brain cells to designing a mechanism or making some obnoxiously complex part. That…. is for a different build coming soon.