Flatpack - 13.6kg BEV

[hhills (Harry Hills)]

Thought I’d continue clogging up the forum with some build diaries!

Feast your eyes on this shiny stainless specimen

Flatpack was built back in the mists of time, the far distant year of 2015. It was one of the first good robots I had made and being about 18 I was yet to find my groove with regard to design ethos. I did what any other starry eyed chronically online ro-bro would do - copy Charles Guan. Without hesitation I ran away from chunky milled aluminium to slick laser cut jigsaw puzzles. Being able to design something effectively in 2d and have it interlock together with minimal effort was great for me. By this point I was working stupid hours in a stupid job selling toasters to morons in a hardware store so time was precious.

Splatted together a fairly respectable robot though and the ole build diary for it can be found here

It ultimately had some problems. Early days of brushless, being clouted during a cease and being made out of stainless in a full combat environment being the chief ones.

A few months later seven years had passed and I had moved down the road from a very popular venue for the fun centric sportsman class of BEV’s. I had tried my hand at a couple of interim builds but getting Flatpack out of retirement and giving it a fair whack at some rough and tumble was too hard to turn down.

I opened up what I could salvage from the old CAD model and cursed my horrific bad habits. A lot of sketches were cleaned up and models redrawn and I could try pushing parts around. I was fairly set on keeping the core of the lifter (pretty much the only useful remaining part) and just making a minimal frame to pootle around the arena with. The rough draft just used classic old argos drills LIKE WHAT MOTHER USED TO MAKE.

I went a little harder and switched up the drive so some more powerful 775 dewalt drills, had a cleaner sweep of components and a more reliable setup for the lifter motor. The plan was to get some HDPE cut (laser’d actually) but that fell through so I just simplified it to what was cheap on ebay and I could cut by hand.

In true bargain bin BBB spirit I found a dewalt by some bins and after stripping it found it to be really pretty nice inside - like a normal drill but lärge. The speed range worked out pretty well to - topping it out to 1100rpm in high gear and 330rpm in low. This put it in the 10mph range which is pretty sedate but still may prove too much for me in a small arena.

I had my bulkheads lasercut (again out of 5mm stainless for old times sake) and you can see how the drive motor interlocks. I love technology. Making a 00’s power tool fit a 2023 fighting robot is a breeze with lasers and a SW licence.

The wheels are 3d printed hubs with polyurethane tyres. The white on the right was my first slightly globby attempt and the grey is my “production” version. The front wheels have two 12*28mm ball bearings and the rears have a 17mm hex for a mini/morris wheel nut.

They each have a HTD5mm timing pulley drawn in to get that funky fresh 4wd.

In order to fix the corner I digitally painted myself into I once again returned to the parallel mounting of the lifter motor. The gearbox is one of the mystic and illusive Saturn 64’s driven off a single chain stage by the original SK3 motor.

The motor has a custom sensor board which the lovely Si Harrison helped develop and manufacture. The gearbox housings are also 3d printed in a ballsy move - I had wanted machined aluminium but couldn’t quite bring myself to spring the dolla it would require. About 50 pence of filament seemed a better deal.

Back when I worked in the nightmare carbon factory I had a lot of time to kill and so this little lad often came with me to work for the week and I could get odds and sods done before returning home for the weekends. I was able to test the theory of the lifter mechanism pretty well here.

I was intending to get this running for last year’s farm bash but it clashed with the opportunity to see a running Tiger 1 tank so it sat in this state until December time when I could pick it up again and look at finishing it off for the event at the end of the month!

“armour” is fitted in the shape of some 5mm aluminium and 6mm UHMWPE and I have had it running under its own power which was pretty neat. The gearbox is getting a slight rejig and I need to draw up some internal braces and mounts for boring parts like ESC’s and links but it’s way more robot shaped than it has ever been. Watch this space!

[Jack (Jack Franklin)]

looking like a lovely feather Harry, look foward to seeing it in action!

[hhills (Harry Hills)]

Cheers Jack, feeling a little outgunned compared to modern robots but should be all right for a knockaround.

Looking fairly sweet with the wedges and the side armour fitted.

Progress trundles haphazardly onward. Not quite as much got done as I hoped this week as I got bumped back to nights but I got into a decent routine of getting a few bits done in the morning before I crashed out.

I decided to reprint the weapon gearbox parts in PLA-ST as sitting over time the solid ABS had fractured at the bearing bore and it wasn’t a great print anyway as it was warped on one (non critical) corner. I’ve not touched PLA seriously in a long time as I tend to write it off as a material. I take partial blame for this as I buy the worst bargain basement filament known to man and don’t bother dialling in any settings for it. I took a little bit of time with this and while it’s not perfect I have two respectable parts out of PLA - ST and they feel robust enough to chance chucking them in a robot. Big ups to tree supports also. Love em.

Downside for maintenance is the whole bloody side has to come off to get them in or out which may prove frustrating. It did plop right into place in a pleasing manner though so it wasn’t a huge hassle.

Gear and key have been fitted on the output with a liberal application of our lord and saviour Loctite 638. The sprockets are going to get the same treatment as they’re only retained with a pair of grubscrews. I will flat or put a recess in the shaft to seat them a little better as they want to slip on retract sometimes. Potentially worth going up to an M5 too to be fair.

All slapped together and it worked pretty well on the first try! It sounds a bit rough, mostly due to the Insane Transmission Stack Up (& clown posse) but it is functional enough for the farm.

Still loving that motion! Wiring is going to be a bit interesting. I need to grab some heatshrink, some more wire (which helps for wiring I find) and something to stop any potential shorts on a metal chassis as I have to run cable over under and through everything.

Featherweight Combat Robot Lifter Test

[hhills (Harry Hills)]

Flatpack has finally had the wiring loom sorted and it can move and lift at the same time which is great for being a week out from the competition. It is a pretty poor showing compared to what I’d normally aspire to as I tried to hardwire as little as possible and keep spamming XT60’s to try and make my life less of a headache on the day if anything blows up.

As I clunked through my parts bin I found one of these combo link/fuse/light mounts I made a bunch of back when having a decent printer was new and exciting and I was still tentative about printing personal things during work time and with company material ( I very quickly became much more callous at that job and ended up rebuilding multiple feathers and a heavyweight in the workshop and nobody bothered me about it. I do wonder why it we went bust…)

You can see one in place here on the ill fated side flappin’ lightning style Flatpack THAT WE PROMISED NEVER TO SPEAK OF AGAIN

I elected to give it a whirl and a last outing in this Flatpack as it will be fitting to end out the era and really simple to kill 3 birds with one little PCABS stone. It takes a maxi blade fuse as the link and has a cute little technobots LED screwed in.

Running 4s in the end as I found the two surviving Hobgoblin drive packs and they took a few cycles without bursting at the seams and unleashing a lithium scented death mist. I need to cut up some foam padding (wilkos has gardening kneeling mats for a couple quid at the moment for all interested parties) I’m pretty sure the drive motors are 9.6v native so it adds a decent amount of pep. I still am in great need of a lid and have ordered some HDPE sheet to hopefully get here in time for me to pull a rush job one evening but if that fails I’ll have to make do with some chopping board or similar.

Roll on Saturday.

[Joe (Joe Brown)]

I for one greatly appreciate the side flapping, I don’t think I was into the hobby when you built that, it looks super cool, very fun weapon.

The final build of this Flatpack looks incredibly clean though, awesome stuff, can’t wait to see it in action on Saturday!

[Craig (Craig Croucher)]

Always loved flatpack, excited to see it revived! And yes the side flipper is very cool

[hhills (Harry Hills)]

Gosh, well wasn’t that fun.

I managed to nab some sheets of HDPE in time and was able to slap together a passable lid. Frustratingly they weren’t quite lined up and I had a 3mm gap where the two sides met in the middle but hey, it’s BEV spec and I was short on time and inclination so I just sent it.

The more eagle eyed among you will notice the addition of some draught excluders - which serve a number of stupid purposes. It was a funny idea (more amusing in concept than execution I admit) to give a smidge of ground game without trying too hard and it was a way of gently sweeping the arena of any debris. It also functioned as a false moustache as part of a clever disguise “well no sir, this isn’t Flatpack of old, it is An Brand New One”

It was finished up in the morning before I made the long and arduous journey to Crewkerne. Once there I stood around awkwardly for a hot minute before I remembered the broad strokes of human interaction and, more pressingly, that I had a robot to tech check. All good and it flew massively under the 11kg mark so that was handy.

I got a beer and charged batteries to wait for the first fight. My draw was first up with the super cool Hell’s Angel and the remarkably pointy Talon.

Dave ran the frying pan which made an amusing ‘Clonk’ when fired into other robots or the floor. My two opponents seemed very intent on waging war with each other so in the absence of any combat I elected to chase a balloon around the floor until a slot opened up. Flatpack was nippier than expected and was able to dart around in quite a sprightly manner. It wasn’t the most controlled I have ever been as I was fighting grip and the floor somewhat but I went the distance and lost out (deservedly so) on an audience vote to Dave and Hell’s Angel. There was some shouting of smoke at the end of this fight but it wasn’t anything electrical. Jury is out if it was a bit of MDF spraying out of my old DeWalt drills or just paint rubbed off the floor.

The one tyre that was softer than the others wore down to beyond realistically useful in that first fight - too much wheel spinning. The others showed almost zero wear after the whole event so I know what works. I had my next fight up against Chris and his wonderful axe robot ‘The Infernal Abuse of Fred’ where we both suffered from silly problems. Him, a grub screw and myself getting beached on the floor. Slightly limp wristed show - the robots too!

I had another beer and tried some critical drinking to solve the problem. The best I could come up with for the least amount of effort was bending the front wedge up at the leading edge to eek out a bit more clearance on that side. Running the robot backwards and forwards on the desk and the ground proved that I still had good wheel contact and I was more confident I could drive over every part of the arena.

Fighting Agamemnon I had a lot more control and was able to ramp off him a few times and generally prove an annoyance rather than a threat. It all ended underneath the Cat. Me trying to drive and lift with an additional 20-30kg on top proved too much for my fuse which blew leaving me dead in the water.

Flatpack did one whiteboard under the capable control of a small child. Amy did a great job and lasted for almost the full fight before twirling into the pit. Mechanically the robot is still pretty sound bar some sheared keys in the lifter output. The prints held up well and electrically it was solid too (fuse issues aside) Lots of cool notes taken for upgrades and I have a much better understanding of how 2 BEV gud.

I see much more power tool abuse and questionable Chinese electronics in my future.

[Nick_DSC (Nick Cole)]

Love a Harry Hills diary/report. When it drove well it was driven very well, but I wonder why that specific wheel wore down a lot faster than the others.

[hhills (Harry Hills)]

Silly thing Nick. 3 out of the 4 wheels were 60a polyurethane and I ran out of this whilst casting the final one (too many FW track prototypes) so in a pinch I cast it in the 30a I use on my beetles.

I think I could have gotten away with it if it was one of the fronts but oh well, chalk it up to experience

[Nick_DSC (Nick Cole)]

Live and learn and all that. But yee, loved seeing it at the weekend. The action on the 4-bar is very smooth and excited to see it again in the future.

[TeamBee (Elaine Day)]

Thanks for letting Amy have a go at driving, she was beyond buzzing

[hhills (Harry Hills)]

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Oh, absolutely I do. So, yes featherweights have remained rather dormant since April but I have been knocking out the guts of a rejig of good old Flatty. For those of you who don’t know my current day job is working at the rectangle factory. What I mean by this is I produce sheet metal parts for large solar farms and when you really break it all down I just make variations on a C or Z section - from about 50mm to 11m long. It’s all just rectangles man, it always has been.

To break the tedium a little I decided to make a robot using the same style and skill muscles I flex daily. I wanted to go further on the flat pack theme for Flatpack and try to produce a frame that’s folded from a single sheet. Limits on my patience and creativity mean that I actually ended up having a frame that’s 4 folded components in the end but one of them is pretty large. These were cut by lasered and I’m hugely impressed by the speed, cost and quality.

I was relatively impressed with the Dewalt drive from the prior BEV spec Flatpack so I got on ebay and tried to nail down some more. A little idle clicking and seven English pounds later I bagged a bare unit and a matching friend for about the same price. The back end will be supported with some printed nylon brackets that are yet to be drawn up.

The main frame is a decent chunk of weight but is pretty simple. The only lightening bit is the silly slots on the side. I intentionally left it a bit blank so I could make my own organic mounting holes for components as it’s all very nebulous at this stage and it’s BEV’s so it doesn’t need to be super serious.

All of the internal chassis is bent as well, alongside the actual link arms for the 4 bar mechanism. I added in the reliefs for the main chassis manually but all the rest is auto generated by solidworks’s sheet metal tools. Most of it is 3mm with a couple braces in 2mm.

I did a little sneaky and wrote a bunch of programs on the CNC press brakes then came in even earlier at work to quickly pump the actual folding out before it took time away from production.

I will say it is the quickest way of batching out a robot frame I have ever done. There are a couple of little wobbles - some hole stretching mainly (steady on) near the edges but it’s dimensionally sound. I got two of everything cut to meet the minimum order threshold so one is fractionally nicer and will be the main one. I don’t actually know what to do with the B grade one as sportsman isn’t agro enough to need a spare.

The links came out really well to be fair. They’ll be bored out for printed nylon bushes for the pivot points. The front link has some extra bolt holes that interface with a spur gear that drives the arm up off the big servos. There should be enough slop though I might change how I have the actual arm setup.

These are the most complicated (read: simple) part going into this robot as it requires me to not screw up a direction as it has an interlocking tab that braces and locates the lifting mechanism into the frame. This is what the 550 based servos I found on AliExpress bolt into. The plan is to have two of them with an additional spur gear stage driving the lifting arm so I can have positional control on the arm and have it on a momentary switch.

It was then snaffled out the door and dumped in the boot of my little old clio so I couldn’t check fitment until I go home. Luckily aside from the hole stretching and a teensy kiss with a file it all fell together into a robot shaped lump very nicely indeed.

The holes on top are piloted for M4 which may prove to be a little thin, worst case they get drilled out and Mr Rivnut Comes Round For Tea. Eagle eyed viewers will perhaps have noticed that there are two holes in the side of the chassis to be threaded for shoulderbolt shafts (with locknut too - not just relying on 3mm of thread!) because I really want go get 6WD on this robot.

For simplicities sake it may remain 4wd but I kept the geometry in to give me the option to live my best life if I can be bothered with the hassle. Next update in <6months!

[Jack (Jack Franklin)]

Working on bev things once every six months is very frequent imho - I barely touch Mucha Lucha!

Looking great harry - really into it. Makes me wanna do something metal - but just feels like so much effort for Bev’s/feathers tbh.

6wd would be awesome if you get to it! And I like the 90 degree gearbox on the weapon motor - a very handy form factor

Your threads are always a good read dude, will watch the progress keenly

[hhills (Harry Hills)]

Not really much to report but that’s never stopped me from posting an update before and I’m not about to stop now!

I stripped down the DeWalt drills I’m using for drive motors and began the slightly grim process of getting the sludge made from MDF, grit and grease off the motors and all over my hands, shirt and doorhandles.

They get locked off with grubscrews the same as normal drills (save these are M6) and still have the metrimperial mongrel 3/8" UNF/ left hand M5 output. That’s why I like these drills in particular, they’re just like a fatter, quicker and larger version of the cheap 550 single speeds. They’re a lot more delicate in construction however and you can’t just slap one where you would a normal drill. They need round the clock support, both emotional and mechanical to keep tickin’

I got a little unlucky with the eBay lottery in that one example is really surprisingly nice and the other is utterly shagged. The gearbox is fine as back in the 90’s and 00’s those Germans sure could make power tools but the motor absolutely has been mucked about with. It has had the flux ring removed, the trigger assembly replaced. This speaks to a shady repair going on at some point. This potentially will need a replacement so I’ll keep the search criteria rolling on eBay. It’ll do in the interim.

I got my gears for the lifter in the shadiest way imaginable. Literally wrapped in Chinese newspaper and taped up and thrown across the oceans. They’re pretty decent and sadly cost less than buying one gear locally.

They fit well though I’ll have to check the centre distance is ok once the bushing is fitted and there’s a shaft for them to sit on.

I have fitted the drive in as best I can to try and devise a sensible way of keeping them supported. Loose component placement is going on too. I’m thinking I’ll run identical bays with two servos, two batteries and escs running down each side. I’ll see what I can dredge up battery wise. See if I have another one of the nice new (old) turnigy 5ah 3s packs else I’ll use those 2.7ah packs I’ve had since like 2016. One of those was even in hobgoblin during RW running the contactor and RX.

This kind of hammers it home how mega they are compared to regular drills. Now I need to look at wheels before I go much further. Wondering how awful round belting will be for a BEV else I’m forcing a HTD5 around with some back breaker tensioners or trying my luck with chain.

[Joe (Joe Brown)]

Looking beautiful! Interested to see how the 550 servos are - particularly with presumably some sort of worm gear in that right angled gearbox?

[hhills (Harry Hills)]

Correct!

It’s a worm stage with one plastic gear which then stacks to spur. There’s some larger 550 servos which are rated the same torque but have a 60mm height and are all steel spurs (though still fairly fine pitch and width) I had a bunch of these that followed me home from an old job but have since moved them on (ones in Calum Jones Sgt bash on turret duty!)

They are fairly legit with regards to torque rating but they’re fragile and precious things, and need special handling.

Any shock and you are having a bad day.

[hhills (Harry Hills)]

Beep beep, c’est moi.

I have been chewing through the details in the background trying to niggle away at odd jobs in a sensible way. I have no clear idea how I want the robot to look overall but it will have some Flatpack themes. What that exactly is I’m not clear on but I’m channelling my inner Potter Stewart - I’ll know it when I see it.

Pulling the first in a long line of ‘pro-gamer’ moves I have elected to once again print structural components in a 30lber. The gearbox and some motor mounts in Flatpack were printed and survived relatively well. They were just PLA-ST and ABS+ so this zesty little number pumped out in nylon should be enough. All of the heavy lifting is taken care of with 3 M8 barrel nuts and a m6 captive nut so the material itself is working to its strengths.

It just stops the motor and the interlocking gearbox endplate from coming back and letting it spit several thousand planet gears out into the black void. I may decide to be clever and include geometry to envelop the ears of said gearbox endplate to stop it from ever twisting. The current plan is hope and a well placed m3.

This absolutely could be HDPE and translating it to sheet material would be trivial with a router template or even a jigsaw & hand plane but printing is zero effort and I am a fantastically lazy boy.

Right onto the most striking development. Track attack baby! So these hunky strips of rubber have been in my possession for a long time (about a decade) and they date back further than that. They are tracks from a Tonka bulldozer, way back in the mists of time when toys were made from metal, had sharp edges and all that yummy lead based paint. While they are lovely and perfect, they are pretty iffy from a spares perspective. It’s sort of uncomfortable for me to track down a vintage toy and butcher it for some rubber. Some things are sacred and I think old toys are super cool. If I find a basket case with usable tracks I am absolutely having it though. Luckily BEVs are sedate enough that I don’t mind chucking these out there to have a run around. I do have some china/homebrew based options that I will look more into if (when) these are damaged.

These trackwheels are just a quick printed test in ABS to see if my ad hoc measurements and PCD was right - they’re close but the pitch needs tweaking somewhat. It’s close though! The plan is to have two idlers and one driven straight off the Dewalt in low gear. Part of me wants to see how they do in high but with that track its effectively a 95mm wheel and that is going to get a bit special in a tight space. Powersliding with tracks would be awesome though.

Loving the slightly mismatched and slightly chaotic grouping of parts. 90’s power tool meets cnc folded frame with Chinese servos, electronize escs, vintage toy tracks and all held together with 3d printed widgets. Beautiful. Terrible.

[hhills (Harry Hills)]

There ain’t no tracks and there never was!

So I changed my mind somewhat and went back to wheels. I was having a lovely day at the Rectangle Factory when I got the call to park my favorite forklift outside as it was long overdue some new booties.

This bad boy was previously running on slicks and the new wheels added about a 3 inch lift to the front, made the tilt work properly and inspired a new set of industrial looking wheels for me robot.

I went home and did battle with the wrap function in solidworks and with a bit of mirroring and patterning I had made an approximation of the cool forklift tread.

The result was this wobbly pink silicone mould which is worryingly reminiscent of the nightmare Dune 2 promotional popcorn bucket.

I haphazardly glopped some polyurethane into this mould around a printed nylon hub. The old ABS ones held up way better than expected so a mechanically stronger material feels like a decent upgrade. I have gone super hard on the tread. I wore the 60a down pretty badly before so have gone slightly overhard with 85a. My aim is the tread will actually have a chance at working and I’m going to be on wood floors anyway so it shouldn’t be too skatey. Heck, they feel softer than the old robo challenge blue wheels we all ran BACK WHEN DINOSAURS ROAMED THE EARTH.

I pilfered the bins and found a suitably scabby 100mm blank. I had intended for this to be 1.6-2mm but I only had 3mm to hand. An extra chunky arse never hurt anyone.

I brought the printed mounts along so I could ensure a decent fit. They’ll bolt with 6 m8’s because they’re the only barrel nuts I have on hand and it’s hilariously overkill.

So that’s about where it stands for now. It’s marginally more complete as deadlines and POM loom like phantoms on the horizon. My next stages will be ordering belts and a second servo to get closer to being mechanically complete. I’ve send some drawings out to get a couple bits made as I feel the path I was going down was going to end up rather poorly.

The back bum plate extends to cover the belt, though it will probably get a little aesthetic kiss with a grinder to knock the corners off.

I’m trying to conjour up how I want the font to look. Something kind of spatula-ey would be nice as I feel that that is easy to make bon destructive to the floor. I also rather like the idea of making the whole front wedge lift up with some cut outs for Uberclocker style outriggers or pokey legs.

[hhills (Harry Hills)]

Since the last post I have now printed and cast all the wheels and fitted belts so the drive is mechanically complete. I need to order a single shoulder bolt and a scab a couple M10 nylocs (my work runs exclusively on M8 and M12 - sad!) but it it will run as is with a shaft collar to space the longer bolt shaft and if I dump a load of loctite into the current nuts.

So going off the outrigger chat from before I went to try and form a shape that looks fairly Industro-Tonka but also could be functional and not floor destroy-ey. I was also trying to make them fit onto a sheet of HDPE I have already so I don’t have to buy more. These are a printed mockup which will double as the router templates to cut them out of 10mm HDP. They’re just bolted together with a pair of M6 standoffs and pivot on an M8 bolt.

Pulling a bit of a gutsy move but slap bang on the front of the robot is a printed part. This little nobble is a lump of nylon which has 3x captive nuts and not much else. It’s pretty high infill and wall so I’m reasonably confident it’s BEV proof and if it does fail the part is still going to be held on by the bolted assembly through the steel. Eagle eyes will note the forks have a radius on the tip to help not dig in or have an edge to be bent up.

Gather round children, this is what your crumby little AliExpress PCB used to be. If you listen closely you can still hear the relays clicking on the wind. This is the guts of an Electronize FR30HX controller which was one of the entry level controllers for the early 00’s right through to 2012 or so when more, better options entered the market at the same price point. Back then it was £50 for one of these or several hundred for something like a Victor which had to come from the far and strange land of America. The control on an Electronize is pretty poor (for our uses) with the direction being switched by a relay there is a tendency for delay and coasting which as soon as you use anything else feels horrible to go back to.

But they’re charming. And they remind me of better (much worse) days. Being constructed of ACTUAL components and being through hole they are super intuitive to work on and repair even for the electrically impaired like myself. The fact they can still be patched back into service after 15 years is not something to be overlooked. I did a few bits of housecleaning, swapped a relay and ditched the horrible old wire with slick new 14awg silicone and slapped on some XT60’s.

Mounted up with the dual servos up front and the ESC’s loosely plonked in place. They’ll be bolted to the chassis but I wouldn’t mind printing a lil TPU mount to give a bit of sponge. In this one you can also see the front link arm is now a lovely machined part courtesy of @JohnWilliams CNC magic. It is now the nicest part on the robot by a nautical mile.

The servo is spaced off with a little printed widget which lets me get to the grub screws in the pinion without disassembling the lot. I also cut off the header pins from the servo and soldered a servo lead directly to them. I really want to get some longer ones as I had to make use of what I had and ghetto an extender on there but I’m not sure I will have the time to strip it all back and work it out. I should also make a cover for the PCB or at the very least entomb it in a nightmarish hot glue cocoon.

I set about making the arm. I had some thoughts but ultimately went for a duckbill spatula style made out of an offcut I pulled out the bins and chucked a couple bends in.

Rubbish photo as my phone camera doesn’t always want to focus because it has had a hard and abusive life. The core of the lifter arm is no longer a folded part, instead it is a bit of aluminum C channel which is just off the shelf with an angle cut one end and 4 holes driled in it. Simple but it works so well. I have to knock a couple more chunks out of it to clear the rest of the mechanism but for about 9 pound it was a great solution. The lifter arm is very heavy so I may end up pepper potting it with speedholes

Still a bit of an ugly duckling but still has some heart in there. I’d say the wiring loom is a bit of a rat’s nest but since having them as pets, their nests are much neater and more comfortable than the silicone coated nightmare I induced. That said it is electrically complete sans link n’ light. I want to plop the RX in a box in the front right pocket and have the link on the left.

I also want to keep the symmetry rolling for as long as possible so I will be trying to slip another one of the 2.7ah 3s packs down the side. The servos really need 24v as they are much slower than the other types I have used. In fact I have seen tectonic plates move quicker. But I have lasercut and folded my bed and now I must lie in it. My plan is to try find and fit some 18v (or even mild 24v) 775 motors to the Dewalts or just go extreme with the transmitter limits and run a 6s system purely to fuel the servos. Though I may also look into hot swapping the 550 motors to something with a little more pump. The positioning is magnetic so it should keep up if I ramp up the speed… maybe?

[hhills (Harry Hills)]

So with the clocks changing and having a couple days off flipping and folding 3 meter bars of steel all day I have had a little more energy to knock little bits off the list.

Bumbling back from the pub I had the sudden urge to operate power tools so I set about making the outriggers.

I was using my old template and router technique to make these parts from 10mm HDPE. I traced the template onto the sheet and roughly tessellated them as best as I could be bothered to.

.

They got roughed out with a jigsaw and were bolted to the templates and shoved through the router. I went the extra step and put a slight chamfer on these just to make them a little nicer to handle.

The assemblies were bolted together with a couple of standoffs and they’re done! It will take longer to get all of the little HDPE slivers out of everything than they did to make.

I also made some spare wheels, though with ulterior motive. I always want to make a 6wd thing and I feel if I can’t do tracks then this feels like a fair consolation prize. When I ordered my belts I also picked up some that were 5 teeth longer so I could look at adding in some tensioners and getting some wrap around a central pulley… Not great but it’s mostly for aesthetics. If I wanted a bullish drivetrain it wouldn’t be 20 year old drills and Electronize.

Pretendobot but it looks even more like a beefy die-cast toy. I think wheels weigh the same as armour so I might get away with it. I stuck everything on the bathroom acslr and I was tipping 11kg with everything minus lid (which will be plastic anyway) so I’m hoping that’s a fair margin for error. I’ll chuck it on the works scale before I celebrate anyway.

Oh I mostly sorted the servo slowness as well. It’ll still be a bit glacial but nowhere near as bad as I thought.