I found a use for the Mobius Strip Tank, check out part 2: kzread.info/dash/bejne/h6iF1M6oeKeZc9I.html

@FIRE_STORMFOX-3692

4 ай бұрын

James I have an idea! I was thinking about how to make the fastest feasible tank, I realized that the real problem is the sprocket system, what if we moved the track with magnetic fields like a maglev, with very low friction between the tank "wheels" and the track, magnetic suspension and acceleration. this is a very sudden idea so I just leave it here in the hopes you understand what I mean, I was literally thinking about the rocket tank the soviets made when I realized that friction is what's really keeping a tank from reaching higher speeds, wider tracks may help too im not sure.

@FIRE_STORMFOX-3692

4 ай бұрын

I got another idea, what if we segmented the body to allow it to flex over surfaces? Almost like a millipede. ( I'm a crazy soviet scientist with nutz ideas if you haven't noticed)

Truly an example of a solution in search of a problem.

@colonthree

6 ай бұрын

ACTUALLY... the tracks will get more evenly worn, lasting twice as long (in theory). :'3c

@TheOfficialOriginalChad

6 ай бұрын

@@colonthreethis is not an issue with tanks due to the surface area of the contact patch being so much larger than if both sides had to be interlocking with the drivetrain.

@Smona

6 ай бұрын

​​@@colonthreealso if the vehicle is designed for dirty ground there could be a cleaning unit on top that cleans the side that's next gonna touch the sprockets

@davidswanson5669

6 ай бұрын

@@SmonaI was thinking similarly, but I’m sure there’s flaws in the logic. Still I like the idea of accomplishing something useful to the “inside” when it enters the “inside” track position.

@conorstewart2214

6 ай бұрын

@@colonthree actually you just design the outer surface to be more wear resistant with the ground and the inner surface to be more wear resistant with the sprockets and drive gears. Making it like a Möbius strip just means that both sides have to do both and hence compromises need to be made making both sides worse at both. So it would wear better and perform better just with a properly designed normal track.

they use mobius strips for conveyor belts, it helps with surface wear

@NekitGeek

6 ай бұрын

Why bend not wear strip more?

@toesandfingers

6 ай бұрын

because both sides of the belt become the surface, rather than just one@@NekitGeek

@DadofScience

6 ай бұрын

I thought I'd seen this in play on mine site conveyors but couldn't be sure that was what was going on. (Edited for clarity, i.e., bad English)

@jaydeep-p

6 ай бұрын

​@@toesandfingershe was asking that wouldn't the bend in the strip cause wear?

@Marc42

6 ай бұрын

​@@jaydeep-pIf you stay well below the elastic limit it should be ok, not permanent deformation caused.

Best line ever..."we don't do these things because they are easy....We do them because we THOUGHT it would be easy" LOVE IT!

@infidelmat

6 ай бұрын

Needs to be a Tshirt

@Izelikestea

6 ай бұрын

a true engineers lament. i legit snorted

@Speed001

6 ай бұрын

​@infidelmat great, now some bot is going to actually do that... those websites that steal content and sell it on shirts.

You would need 11 links for the 180° because it’s the pivot point that gives you that 18° of movement, not the link itself. 10 links only give you 9 pivots so the tolerance was spot on.

@aaronsalmon270

6 ай бұрын

Beat me to it.

@link7417

6 ай бұрын

Its silly really how easy mistakes like that happen but we all have those moments ❤

@regularfryt

6 ай бұрын

This is one of the two hard problems in programming: caching, naming things, and off-by-one errors.

@GeorgeSanger

6 ай бұрын

An example of the fence post error, I believe

@link7417

6 ай бұрын

@@regularfryt i think you had a off by one error there x3 just poking though as I fully agree whit that list

This technique is used in industrial belt conveyors to distribute the wear on either side before you get into the cording.

Actual uses for a mobius track: -If you want a machine to stamp a repeating pattern into concrete, you could make it half the size with a mobius track. -It will increase how long rubber grip pads will last, because they are only contacting the ground half as often. -You could use it for a belt in an airport, again to increase the uptime before you have to replace the rubber gripping surface. -You could use it to tip material off the side of a belt in a factory. -If you put in two twists instead of one, you could have a belt with a different surface texture for only part of it's run. Not sure why you'd need that, but it probably has a use case somewhere. I'm running out of ideas here, reply if you have a good one that nobody else has suggested!

@Hugh7777

6 ай бұрын

You'll have to have twice as many grip pads, or if flat, it will become thinner just as fast.

@ShakesB13r

6 ай бұрын

Its not usefull on its own, but in theory you could use the bend to give the chains a 3D path enabling either: A tank that has only one track (and can only drive straight) or tracks that flip to the side on the top side, leaving more room for armor or the important Parts of the tank on the side.

@luckytrece4985

6 ай бұрын

If you put a pair number of twists it will not be a mobius strip, it will have two parts like an untwisted strip

@robonator2945

5 ай бұрын

couldn't it also double the life of a something like a belt-sander? Obviously it'd still be using the same amount of material, but it'd only need to be replaced half as often.

@bow-tiedengineer4453

5 ай бұрын

Probably not a great idea, because then you'd wear the idler wheels faster, and those are way more expensive than the belts.@@robonator2945

as others in the comments have stated, it would wear both sides of the track evenly. if you put grousers on both sides (single side?) of the track, all of the grousers would wear at the same rate and the entire track would last twice as long compared to a normal two sided loop of track (that only runs on the outside).

@UltravioletNomad

6 ай бұрын

I know that works for surface wear, but I question how this affects the joints between chain links since there's so much wiggle room I imagine those joins might be weaker and more susceptible to vibrations.

@jurajvariny6034

6 ай бұрын

@@UltravioletNomad perhaps make the links not be joints but compliant?

@scilens1049

6 ай бұрын

think McFly... picking up mud and stones, and deliberately twisting the tracks to put all that into cogs and wheels, the wear and tear of the joints... this must be the single most stupid idea there ever was considering all tracked vehicles EVER.

@azrielfriedman3595

6 ай бұрын

@@scilens1049 actually making one entirely out of peanut butter is a worse idea

@scilens1049

6 ай бұрын

@@azrielfriedman3595 dont give him content-ideas :D

James!! Ive got an excellent suggestion for a possible use of the mobius strip treads: cleaning! with mobius treads you could clean debris regularly from both sides, ensuring that they cant get bogged down! Think about it, treads can now go through mud or sand or rocks. One brush per tread means that every two rotations both sides get cleaned (thinking like a bristle brush). Or for overkill, a brush on each corner would constantly clean both sides but the brushes only need be on one side. Obviously this isnt an issue for huge tanks, but for small ones it might really benefit. What do you think?

@k_the_v

6 ай бұрын

16 likes already? Apparently my idea isnt a terrible one, Hopefully James sees my reply...

@Hugh7777

6 ай бұрын

@@k_the_v The, um, flipside of that is that both "sides" pick up mud etc. Think about it, treads have been going through mud or sand or rocks through two world wars.

@k_the_v

6 ай бұрын

@Hugh7777 yes, full size tanks can handle just about everything. However, we're talking 1/4 or smaller treads, so rocks and sand are a far bigger problem.

I'm thinking about using the twist in the track to make the next Bendy Tank! Look out for that some time.

@darth_dan8886

6 ай бұрын

I wonder if there's any value in trying for a tank that contacts the ground _with_ the bend itself. A really narrow track with full drive benefits of a wide one?.. But probably would have lots of sideways forces.

@matteomascaropennacchi2220

6 ай бұрын

Dear james, Please read my comments: I love this Tank wheel and I love yu magnificent Ideas, I love this tank too and its genius❤

@man-great

6 ай бұрын

May be Bentley tank?

@SoaringMoon

6 ай бұрын

10 Links only have 9 connection points. That's why 10 links didn't go 180 degrees.

@dragonslayerslayerdragon5077

6 ай бұрын

I was hoping you'd adjust the pitch and yaw of the drive motors, opposingly so the twists went around them, ridding us of that conventional flat track. Great work btw.

1:50 10 links is only 9 joints, each joint twists 18 degrees, so you would need 11 links (10 joints) for 180 degrees.

@nidhu595

6 ай бұрын

yes, however each one has one link so shouldn't it be 180 anyways?

@77gravity

6 ай бұрын

@@nidhu595 Consider just 2 links, with a single joint, gives 18 degrees. The first link provides zero degrees, only subsequent links provide angles.

@nidhu595

6 ай бұрын

@@77gravitythat makes sense, but what about four links connected in a square, then there are four connections and therefore 72 degrees of movement, since the track is connected to itself, we make up for the "missing" link

@ChrisBLong

6 ай бұрын

A classic Obi-Wan error.

@anthonymadorsky1551

6 ай бұрын

Correct. But the last and first link also joint, giving the total of 10 joints.

One advantage: you could put a larger diameter turret on the tanks. Because the tracks go vertical and create more space in the center for the turret

@shred1894

6 ай бұрын

It would make the tank taller which would be a detriment to it's overall silhouette, which would in turn decrease it's survivability in combat. Not to mention the decrease in reliability that comes with having more than one axis of articulation between each link of the track.

@hamjudo

6 ай бұрын

The treads could cover the bottom of the tank with no gap, while still allowing a turret on top. The tank wouldn't get stuck on top of a boulder in the middle of the road.

@wolfganghorn7492

6 ай бұрын

@@shred1894 but you could sink a wider turret further into the tank, thus decreasing the silhuette, additionally the vertical portion of the track could act as a onetime use spaced sidearmour.

@ESPkenner48

6 ай бұрын

And tracks could act as a side armor, althoug Im not sure if it would be a fail or a feature

@shred1894

6 ай бұрын

@@wolfganghorn7492 First, you will end up with clearance issues for the barrel of the main gun by doing that. Second, using the track as armor is a bad idea because the moment it takes a hit you can't move anymore, which opens you up for follow-up hits.

I don't think there is a practical use for this, but the idea is very original. Great video again!

Sometimes ya just have to build something because it sounds cool. Great work!

I have a childlike grin on my face watching this. I love you for doing this. Awesome.

This was an excellent motivation for a build. It was highly effective at being entertaining.

This is glorious! It doubles the life of your track pads

just when you think he can't make anything more practical and utilitarian he comes out with another banger like this!

"We don't do things because they're easy...we do them because we THOUGHT they'd be easy" I'm stealing that!

Nice video as always :D . As an idea for a future video : Tracks /wheels with convertible (in and out) rubber pikes or plots to enhance traction at a flick of a button . To do it , each blade as 2 plots with outside rubber end , and they're normally retracted by the use of elastics or springs , and at a flick of a switch , a slide plate mechanism push these plots out of the track on the ground side to enhanced traction .

The ideal turning position could be software controled: Only leave 1/3 of the mobius total length as the slippy part (just enough for one contact surface length to be full slippery if in the right position) When turning, software calcultes the exact slippy part of the inner turn circle to be inside and provides torque only to the outside. "Tank turn" unfeasible though.

@Nevir202

6 ай бұрын

Could be done, but you'd then need stepper motor so the controller would know where the tracks are, and to calibrate regularly incase the motors lost any steps, or the tracks slipped on their sprockets. But I think you've misunderstood the issue. At 12:02 he points out that in the situation where one side is slippy and the other grippy, it CAN'T turn because the grippy part just drags the whole thing forward. SO what you'd actually need to do, is make sure that if you give it a turn command, it only tries to turn when both tracks are in the same phase.

That's a very cool tank build. Very nice.

Impressive build as usual!

If you were able to switch between the Mobius strip version and the circular version, then you could easily flip from sticky threads to smooth treads as needed. Just stay in circle treads all the time, use the Mobius pattern to switch to the other side, and then go back to circle treads. Great way to give you two options for driving around

If I remember correctly if you cut your mobius strip again you get 2 interlinked twisted loops. Love the idea for the tank. Keep up the great work. God bless

@mkesenheimer

6 ай бұрын

No, this is the case if you cut a doubly twisted loop in half.

@darreno9874

6 ай бұрын

@@mkesenheimer I'm sorry that is not quite right, make a mobius band cut it in half and then in half again along the strip and it creates 2 double twist mobius bands intertwined. The first cut makes a double twist mobius band the second makes what I've described above. I've just done it to check, give it a try 😁

@mkesenheimer

6 ай бұрын

@@darreno9874 Ah, I misread your first sentence. I tried it out. You are right, if you cut the möbius loop again after cutting it once, you get two interlinked twisted loops. However, my statement is also correct. If you cut a doubly twisted loop, you get two interlinked loops.

I wonder if the tank can take advantage of the articulation of the treads to better deal with uneven terrain.

What might be an interesting use (although a bit of an engineering challenge) is to make the twist switchable. So In normal use, you'd have non twisted tracks with either the smooth or grippy side in use. Then when you need to change grip, one of the track joins would twist on each track and allow both tracks to do one loop and effectively change their surface over. It wouldn't be a Mobius strip then as such, but the twist capability of the links would allow this 'flip sides' option.

@Stereomoo

6 ай бұрын

Maybe make it a single link that's split, so it can spin 180 and then lock back together, rather than make one of the joins even more complicated.

@ZwilnikSF

6 ай бұрын

@@Stereomoo Yup that could work. What I'm thinking is with the 18 degrees of spin rotation in each of the links, you could effectively flip a join around somewhere so the following links rotate around by the time they get to the front sprocket wheel.

@Stereomoo

6 ай бұрын

@@ZwilnikSFif you had a little knob sticking off the ends of one of the links, you could have a slot next to it on the body that either has the knob continue straight along (no change) or diverts it to flip it the other way. then you just move the slots while it's on the bottom part of the track, and whichever one's available back at the top it'll follow. Then have a free 180 pivot between that link and the one "ahead" of it. I guess really you'd need 3 paths, continue straight, then 180 clockwise and 180 counterclockwise. Though possibly it would untwist on its own if you let it. (or springload the loose link to encourage that)

Lawn mower tank? There may already be one in your videos, I haven’t looked. Great content James

I kind of want to see a mechanism that can deploy extra grip on tank treads with the push of a button. Maybe it can rotate a cam that pushes down on a spring loaded grip in the tread as it runs underneath?

1:50 If the difference between two links is 18 degrees you have to have 11 links to get 18 degrees 10 times. It’s not because of tolerance, which you seem to have gotten spot on right away. I really liked this video, well done!😄

Hey bud what a interesting design challenge, nicely executed 🎉

It would be a good tank for shedding muck and debris from the treads. Good for preventing jams and wear

@jurajvariny6034

6 ай бұрын

idk, the debris would fall back to the bottom tread..perhaps having air compressor to clean up instead?

@jasonyesmarc309

6 ай бұрын

​@@jurajvariny6034or a rectangular surface halfway down to bounce debris outward like rain on a slanted roof. That way you don't need to run a compressor.

Well, that's me subbed to this channel! Nice work.

Awesome project mate ❤️❤️✌🏽✌🏽

This is great project, bro

When I saw the thumbnail my first thought was "why would you want to do that?" Fortunately, you answered my question right at the beginning. :) Also, pedantry time: a "bogie" is an assembly of two or four wheels that is independently suspended or articulated. That is, the wheels are (usually) fixed in place, but the assembly is suspended or articulated independent of the rest of the vehicle. With your design, the wheels are just fixed to the frame, so there's no bogie involved. Which means they're not "bogie wheels," they're just road wheels.

@8:01 extremely glad you made the tracks symetric 😂

I love how when you commit on a project, you commit fully. You cover a print bed with a whole tread piece.

To reduce vibration, move drive sprockets(any sprockets really) away from the ground. Add grooves to track segments and corresponding lips to the rollers to keep the tracks aligned on the ground.

This reminds me of screw tanks. Might be interesting to try to make a version that can drive on the twist without going flat (don't know how it would work though).

Well done!

These guys are amazing! Thank you for the great educational content! Mobius Single track! (tracked motorcycle?)

With 10 pieces you only get 9 joints, so you need 11 pieces for 180 degrees I think. What an inspiring, curious video! Thank you!!!

Another fun video thanks James. I want to build a tank for my kids to ride on/in but don't have a feel for motor size and drive train they are about 20kg but want it to go up a decent slope. What motor /battery combo would be about right. Thanks.

Could you have an adjustable grip on a tank track by have an inside and outside that have different properties and then slant the tracks in or out depending on the desired property?

fascinating. Makes me wonder if it would be possible to have one really long criss crossing belt with forward only mobility or possibly tracks that extended around the side in some kind of nested pretzel situation.

@bmxscape

6 ай бұрын

yeah look up how 3d printers move the print head

@2:02 LOVE it, lol. "We don't do these things because they are easy, we do them because we THOUGHT they would be easy."

@Alluvian567

5 ай бұрын

Wish you could do clips less than 5 seconds, that one is a clip I would share, but really needs to be 3 or 4 seconds long.

Great video!

is it better for longevity? the opposite side of the track normally doesnt make contact with the ground but by swapping the sides constantly it would reduce wear?

You're telling me a worm drives this gearbox?

I think that is brilliant engineering.

It would be interesting to see a special link in the track that can spin 180 degrees, and a system that can switch it's orientation to add the Mobius effect for a single loop of the tracks, and remove the twist after that loop. This would switch which face of the tracks is used on demand, meaning you could engage or disengage the extra traction on demand rather then it switching on its own each rotation

That's pure genius! Maybe one day we'll be able to invent one without the twist in it

i got a question related to your previous tank with the wheels on the links, if you just had 2 tracks would the wheels in the links let the tank turn better without rubbing the tracks on the ground? cause i think that would put less stress on the motors but let me know if im wrong.

Just interesting to see a comparison of the same parts running with a flat track.

Have you considered slots instead of holes to allow for adjustments during assembly? Or does that not work with the 3d print material?

what happens during/after the transition period between flat and grippy lengths while on a smooth surface like the big ramp?

Could you which the side of the möbius strip on the fly and use the twist part to help dig a tank out being stuck in mud, sand, and snow?

I wonder if a mobius strip pulley belt could work. What effect would it have compared to a typical belt?

How long is the print bed, you printed the body slices of the tank on???

1:41 No, there is no tolerance error. You calculated it perfectly.

-This has probably been done before, but as you described the issue with long track vehicles like the megabots experiencing high friction when turning...- -Could you add lateral wheels to each tread link to grip in one axis and slip in another, reducing the friction?- -I can foresee issues with more focused stress on those wheels and their bearings.- -Possible solution would be a spring loaded pads which may slide laterally but spring back to center position? (Not sure how that'd cope under stress)- -Of course, the more parts you add, the more maintenance required and more potential points of failure, especially when applied to each individual tread link.- -I'd love to hear your or others take on this problem and solution.- Just saw you have already made a video on omni directional tank treads, about to watch it now. Sorry

It would be fantastic if there was some sort of link in the middle that you could control to have it be either the smooth or the grippy part.

I guess one advantage would be for this design if the tank was running in an extremely muddy/wet environment where the effectiveness of the tread grip is compromised, you could have a brush/cleaning device within the mechanism (maybe by the bogey wheels) to clean the outer tread surface whilst the tank is in motion. Although the outer tread of most common treaded vehicles are designed to allow the tank to negotiate the terrain without cleaning.

@jamesbruton can you use them upside down in water as a wormwheel for propulsion?

you should 3d print a custom slope-rig. maybe something on a screw so that you can finely adjust the slope while doing a friction test. this would be cool because you could find the exact limit for friction, and itd be a bit more repeatable than just finding a nearby object to prop it up to some random height. and mabye you could have a tweakable first step height, so you can figure out what the largest step things can go up.

An interesting use would be for sand traction, with the twist on the bottom it would dig into the sand to go where it otherwise couldn't. With a flip mechanism it could then go to flat track mode for hard surfaces

"we don't do these things because they're easy. we do them because we thought they'd be easy" i felt that in my soul

James! Maybe a quick clip in your next video. How well does it run upside down??? Would the tapering contact patch and tilt backwards help it with mounting taller objects without extra grip pads?

What if you had active grip? Like a cam that press the grips down with a servo, or lets them fall into a recess when not needed.

Interesting! With the two different tread surfaces, you can *eventually* execute a turn, and you can *eventually* climb up a smooth incline. That's a pretty good compromise in my book!

The advantages I can think of is that you basically have double the surface area to wear out, so the lifetimes of your tracks are extended quite a bit. It's not a lot of flashy functionality that you gain with it but cost-wise a mobius strip might have a big impact. The fact that the tracks can pivot in an extra dimension might also make your tank able to deal with even more uneven terrain than a normal track can. for example if they can twist when in contact with the ground (might have to redesign your bogey wheels for that) they might make more contact with surfaces that are tilted differently perpendicular to your track.

When I saw the thumbnail, I said to myself, "It's cursed. I love it."

"We don't do these things cuz they're easy though. We do them cuz we thought they'd be easy." Inspiring words 😂

Would it work if you flipped it over and had the twist on the bottom? Would it have a better grip?

every time this guy says "track" it reminds me of duck quacking and i cant unheard it anymore

Very cool. I wonder if more twists would let it drive in water better. The twisty part maybe acting like a corkscrew propeller.

“We don’t do these things because it’s easy, we do these things because we thought it would be easy” As a programmer who has tried to write things to do a very simple task which ends up being a lot more complicated than just doing the original task, I have never heard a more true statement.

a twisted upper tread causes more friction which is amplified as the tank's scale increases closer to real world proportions and it may still work but it will also cause more stress on the treads. You'll also need to re-engineer the rollers to handle dirt and debris being carried into the inside of the tread.

Just curious, what machine you will make if flipped it and using twisted part on the ground? Maybe it will be like use screw shaped driven mechanism combined with belt mechanism?

Mate didnt know you could possibly have so many sponsors in one video.

We're gonna need these mobiius tanks to fight in the upcoming hyperdimensional wars

Thinking about this being used in an armored vehicle made me realize this would be horrible for going through the mud. Instead of most of the mud being blocked by the track, all the mud gets forced between the track and the drivetrain because the track now only has 1 side instead of 1 "clean" and 1 "dirty.

what kind of filament do you use for these engineering projects?

Hello! I love your videos and your projects! What CAD software you use / what software would you recommend for beginners?

I love it! Curious why you’re not using slots to help with tensioning (vs making new gray parts), apologies if this was explained in another video, I haven’t watched all of all of them ;)

Equal wear on both sides, but greater potential to get muck onto the sprockets? The flex between sprockets will probably also have pros and cons. Interesting stuff!

Interesting idea for a harvester if you think about it. Because what was outside becomes inside, it could be made of scoopy cutters and drop off stuff in to a wide chute out of the middle of the wheelbase to the centre of the vehicle when the tracks twist after bringing it up.. might need more action on cutting since track segments stay still when down... anything not cut gets squished.. maybe it has a purpose though.

Is there any way that the mobius is beneficial for kicking off dirt, potentially? Or alternatively, some way it could be used for deliberately picking stuff up and then dropping it into a bin of some sort under the twist?

Suggestion: rather than using Mobius track with uncontrollable switch between rubber and slick sides, make a rigid (standard) track with rotating central part within each segment with one rubbery side and one not. I mean, that each segment may have H shape, where vertical lines are the axis, that connects it to other segments, and horizontal central axis allows perpendicular rotation of a flat part of the segment with a pad on one side. So the track will look like this: HHHHHHHH. Then you give the track no freedom of perpendicular rotation, except in the upper part of its trajectory, where you put a mechanism to overturn pads controllably, when needed.

@MatchaBarnes

6 ай бұрын

Great IDEA!

@boss_bonard7573

6 ай бұрын

cool idea!

would be interesting to have a double twist such that along the ground you have smooth treads, then a twist to a grippy tread that could be lowered as needed, or raised when turning, then twist back to smooth again at the other end of the tank. wouldn't be a mobius then, but still a twisted tread tank

This track design might work quite well in sticky mud - The twist will allow the mud to fall off.

Would like to see it driving on the twist side. Surprised you didn't flip her over!!

I want to see it full size now... colinfurze??

Sometimes it seems this channel is on a mission to explain to Matthias Wandel how useful 3D printing can be. 😀

@arifinaja963

6 ай бұрын

I wonder if people know this name

I'm thinking about the problem you mentioned with tracks needing to slip a little. Could you do a treads made of lateral bars that turn in the direction of travel? Think of something like a snake.

i imagine for the desync of the smooth and grip parts of the tracks that maybe having tracks that could go 180° on demand could resolve the issue, like a mobile piece in the upper part that would make the 1 way track flip to the other side. i wonder if that's possible or even make sense

Where do you get those handy worm gear motors from?

There might be an interesting way to expand on the idea of rotating the tracks along multiple axes. Using some sort of doughnut shaped sprocket and idler wheels might allow the tracks to self adjust and change their angle with respect to the tank over the surface, while the top portion remains flat with the body of the tank. It may be possible to make it so that the tracks form a 90 degree angle with each other (both at 45 to the body) at maximum angle to maintain contact while driving along a valley, or V-groove or something, instead of riding on only the edge of the track. From the front, the tracks would look like \-/ when the terrain looks like \ / instead of l-l

2:03 I think "We didn't do these things because they are easy, but because we thought they would be easy." might be my new shop slogan.