Open Source Ecology OSE Apprenticeship, 14 Oct 2021

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From YouTube: OSE Shredder

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Will it shred? Design concept - https://docs.google.com/presentation/d/1gBzUfp90sB8Ad_KbpchvK54A7JNbo0TJ4ZqT5qIOIP4/edit#slide=id.gb328b2d63d_0_9 - Development Template - https://wiki.opensourceecology.org/wiki/Open_Source_Shredder_v21.10

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A

Let's cover the filament shredder, well, the plastic shredder. So once again, where do we find this info? uh Follow me on the log here: the osc shredder concept, design and cad they're here already, so, what's the concept design look like.

A

And what's the cad look like um so concept is, that's that's the concept.

A

Two powerful motors three inch: bearings three three-inch shafts. There's a shredder chamber, shredder mounting table.

A

uh Additional things in here that we don't show are naturally blades and spacers, there's also scrapers on top, which are fingers that come in from the like from the edges. So you you're like clearing off any plastic. That's I think it's just to clear the blades. The plastic doesn't end up collecting around the blades um once again, precious plastic shredder is a good thing to look at for comparison.

A

And here's- I just put this thing forward here and here I showed the bearings on the inside and it's when we talked about that, but I actually, uh let's put them outside and the way they do it in the precious plastic is what was the idea for putting them inside it was that the blades go right up against the flange of the bearing and therefore rotate against that, and you have no wear no wear wearing of parts, but you can achieve the same if you put the bearings out and put a little collar that goes butts up against the blades.

A

Now that's convenient in that the the bearings are accessible and free of the melt, the shred zone, so it does make sense. uh So let's do this. We do have this three inch, bushing material just cut slices to whatever size we need there. So what does the cad look like? Well, shredder pro? They say it costs 2200 bucks plus motor.

A

uh They they actually do have quarter inch plus what no plus motor, which will be. I don't know another thousand or two.

A

The gear down is the big deal there, motor they say no motor and gear down. That's that comes kind of together. Typically, what are their.

B

A

They got this particular figure of um like 2000. They talk about torques, that they're running at full operation at 2, 000, newton, newton meters.

A

uh What do we have.

A

Well, first of all, let's think about what is that, like two thousand, can somebody picture what two thousand newton meters is? Let's talk about two kilograms to kilogram meters.

C

B

D

A

Like yeah, how much you're pushing at that meter distance like if you're spinning something it's pushing you so 2000 newton meters, what they recommend is about 200 kilograms at one meter. So, like you have this lever, you hold it there, it's 200 kilograms. So right there, it's a lot.

A

Our system has three times this.

B

A

B

Has three times.

A

C

That's the 370.

E

Titanium plastic.

A

Well uh say what.

B

A

It's we're using the large hydraulic motors. We are.

F

A

Of the game on that.

F

A

So what do we do? Yeah? This is not filament makers. This is um heavy duty shredder. So this this kind of stuff like getting towards like shredding making gravel for driveways, is uh where you want to go with this.

C

So my take is that hydraulic motors just do.

G

A better job of being able to take like torque and retention and resistance than electric motors.

A

And then some yeah that's an understatement. Yeah I mean they're just much more robust, much more torquey, much more lifetime, they're, all enclosed they're self-oiled, because they they're they've got oil so as opposed to gears on the outside, like in their system. It's all internal lubricated in in uh what is called hydraulic fluid, which is an oil so.

E

How do hydraulic motors fail? Basically, because if they lose hydraulic pressure, then that's the only way they lose their lubricating.

A

Well, for example, if you're, if you take a car with hydraulic motors down a large hill, you're, still spinning the motors by an external force, okay, so you're going across your rockies there, it was nice multi-mile, yeah,.

E

An insanely, far distance yeah, you keep them up too much.

A

Yeah and there'll be a little bit of residual hydraulic fluid in there and actually, if you're not putting a lot of force on them, it should still be fine. It's like yeah yeah, so.

H

That's cool cool.

A

No, I haven't really had them fair, like these ones know what you can see is leaks like if you blow out a seal because they do have rubber seals. um I haven't really seen that I have seen the small pumps which are connected to the engine. Their seals can blow up yeah like if they're driven, dry, yeah. They they heat up and and get destroyed.

A

You can't pump them anymore, um but no they're, quite robust. The cool thing about it is compared to electric here. You've got enclosed parts, so it's good for dirty environments. That's a that's a cool thing and they have so much torque that you can. You can drive them at multiple range of speeds like you can go super slow.

A

So, for example, you can have a single solar panel, like 300 watts, on our tractor, and we will move that it will move slow. It will move like very slow, but it will have the same torque. It will still push that 4 000 pounds, so you can think of, for example, a great application of these solar hydraulics, which I think is coming. That's that's like everything's gonna go to solar autonomous hydraulic because um or it could be electric too, but hydraulic is easier.

A

uh The complexity and cost factor is it's literally like 10x over over electric right now or.

G

When you fly new flywheel hydraulics.

A

When flywheel to hydraulics you'll need some wind some wind to do it, yeah.

A

um 10 minute lesson: so what do we have here?

A

Like that's the current design, so I mean there's nothing here, but uh so hydraulic motors they're actually just put two of them on what you could do is you can have a gear between the two shafts, where one shaft drives the other here we, since we have spare motors, we can use them directly, they're connected to chain couplers, double uh double chain couplers with 80 chain 80 weight chain, which has like a working strength of like 4, 000 and breaking strength of like 20, 000 pounds or so there's plenty of give and strength in the couplers.

A

Get you twice the torque. So if you drive it with two motors, you've got twice the torque. um The bearings are on the outside. It's a box, half inch steel, eight inch. We need a table for this underneath it we want to put a screen, that's that conforms to the actual blade well since our blades. So here what I did on the blades, what's what's this blade stuff happening here?

A

That's cut out of an 8x8 square. I just drew something up, uh but the thing about this is that if you have this on a shaft, if you just did a circle, they'd hardly meet up. But if you do it on this diagonal there they will overlap quite a bit. So this blade using eight by eight inch, half inch wide half inch thick plate.

A

You can get good overlap with the blades, because you do want that. You want them moving against each other. It's like, like scissors, that's kind of scissor action there. Now the blades in the middle, like they won't, engage much.

A

You might have like a like the blades in the middle. They might allow like bigger chunks to fall in. So, in fact, this kind of blade design might be advantages to chewing up things that in the video that we were watching yesterday, they would actually chew things up because, for example, imagine you put a round thing inside this shredder. Well, the teeth can't really grab it. But now, if you have that flat spot, oh yeah, the teeth might grab that because it falls deeper down into the mouth. So I don't know.

A

Maybe this will actually work better for grabbing hard to grab things, but it's not as efficient in terms of how many bites you take per minute, because mostly the outer teeth will be doing a lot of the.

D

The shapes of uh machines that are swallowed in plastic they are around, but the teeth were only like three or four of them, and they were kind of square themselves, even though it was a round shape.

B

D

Think they sort of thought out that process of having something that looks into it. What's.

A

D

Invariably, yeah, it's deliverable enough to small, pretty big things but yeah, because you're getting less teeth.

A

Yeah yeah, it's just there's different ones, there's ones that have a lot of teeth for for, like taking more small bites for a smaller particle size. If you've got bigger teeth, you just grab bigger bites of things like the big shredders for rocks and things yeah they're huge, and they have a spacer.

E

Needs to basically the the furthest longest point, um so the corners of the of the cutting blade, the treading blade, need to basically practically touch the spacer of the other shot right.

A

Yeah practically touch come close to it like I would leave some gap like 10 inch or something yeah. um But what do we got.

G

Okay, so I feel like in my mind this whole entire time. I was imagining that these blades were going to corkscrew up both of the shafts and sort of turning it in with each other, but these are distinctive.

A

They're distinct blades hung on a square shaft, so the cutout there is.

A

Well, what's missing there, it's the inner tube right! So what's what this is riding on?

A

Is that ah I'm not gonna draw it right now, but you see the cutout is square. That's the the four inch tube half inch wall, which goes around the shaft, the shaft we so through the holes. Just like we did on the tractor. We welded on and that's an easy way to address the issue of having huge, hexagonal shafts. Typically, people might use like a hexagonal, shaft or whatever here we're taking off the shelf, three-inch material and off-the-shelf four-inch tubing and making it turning into an attachment system for high torque attachment system for blades.

A

So that is not going to slip on you, it's geometrical hold and we will uh slip them onto the tube one by one. So these can come off. We can, if you don't like these blades and put on some other ones.

A

If we don't like this, we'll put on quarter inch uh like eighth inch, bl yeah quarter inch is what oh yeah so uh precious plastic uses quarter. Inch blades here we're using half you'll, get twice the bytes out of quarter inch blades, but about twice small bites and maybe we'll end up doing that because we want higher throughput of smaller particles. So we do less screening and take smaller bites altogether.

B

So how do you mount that again, I don't know.

A

So you've got the square tube on this right around the shaft, like on a tractor truck.

E

Theoretically, same.

A

Thing as on the tractor wheels.

A

Easy way to do it, I mean this is a hard problem, but it's a simple solution, because otherwise you'd have to get hex shaft, which is a specialty product. It's it's not cheap um and you don't have hex bearings that size. How are you going to get hex bearings of of three inch size? So what you'll notice yeah take a look at uh the precious plastic video to appreciate the complexity they have to go through because they're machining everything down they're machining hex shaft down to rounds, because you can't get hex bearings.

A

We can actually print hex bearings like we've done them some prints up to like one inch, shaft hex bearings.

A

But if you look at it's actually useful to appreciate what they're doing uh for you to get a feel of how radically we're simplifying this. So if you look at shredder pro.

A

Build it yeah, take a look at that video and look look at the heroic effort they're going through, so you got lathes and.

F

To make a full and continuous weight.

A

But look at what they have to do so look at their shaft. That's all machined.

I

Wow look at this ninety-four percent of people believe company culture is important.

A

B

F

Insanity I mean look at one face: how much effort.

A

Is it to machine that shaft.

F

And again, a braid switch one face counter, clockwise, etc so to assemble.

A

This axis, you also.

B

Start by the bottom, also leaving around one millimeter.

A

F

On this one, the teeth of the blade should face clockwise, and you should so. I mean look at this.

A

I

A

Video, it's a nice video. They do a good job, communicating so yeah and you know they they go.

F

Box laser cut plates, yeah cnc, cut open right. All we're going to do is electric box starting, but optional step is to weld four of the thread bars.

A

To have a faster maintenance job.

F

Then you need to prepare your plate by oiling them, as we will, but not paying.

B

Them due to tight.

F

Adjustment in terms of price.

B

The bottom plate so yeah we'll throw.

A

Their shredder prepare.

B

The side, walls and.

A

B

F

A

Access to everyone on the planet- that's not it. Ours is more likely than removing they can talk about even 3d printing. You.

F

Might need and for this task, lift the two axis together and slide them in the box.

A

Then reinstall the middle plate, that's part of the ecology, here's a little higher attack, great work and it's great.

F

Center, the axis by placing few static leg, couplers measure.

A

F

D

Nut and the side.

F

Wall, you have a collection of adjustment.

A

Spacers, I would advise to laser cut a bit more than needed.

F

Place the needed number to make it touch the this will avoid your axis. To move then install the bearing and tighten them to the same torque.

E

B

Everything's really well, then place.

F

The fifth place: no.

B

Install the gears close, the box, bearings.

E

F

A

uh We could sacrifice.

A

From one sprocket to the next here we have two sprockets next to each other, with a chain wrapped around two of them. It's a double chain and it's a flexible. It's a flexible coupling high strength, yeah.

I

Yeah but the shaft is not correctly connected to the motor.

A

B

But you can drive.

C

It's not a step coupler, it's got play, but we drive it more or write each motor individually. Is that correct? You can.

A

Just because I'm wondering even.

C

If there could be a configuration where you beetle one motor back, you know and oh.

A

See that's the thing uh in um because.

D

Here they are fixed right guys. I mean they're.

A

D

So you cannot control them.

A

You cannot control them individually, but here we can do differential speed based on speed control of each motor. So that would be another feature. The other thing is when you get stuck like, say you throw a wrench in there literally, you will back up and do that kind of motion. We could have, for example, a sensor of our controller, which says if the voltage reaches higher or no no pressure gauge.

A

If the pressure gauge on the motor reaches a value and we have those, we use that in the ceb press- that's how we sense uh where we press the bricks. So you just do that? Reverse it. If you see that happening, reverse it and chew it again, that would be custom code. That's not in marlin.

A

We don't have that there, but uh if.

I

G

Take one of those motors and do something else with that.

A

Yeah yeah, that's the whole modularity of the building block construction set approach, so we use the same thing. We already used those motors same motors on the large trencher wheel like the six six foot trencher. We use them on the tractor wheels. We use it on augers and now we're going to use it on a shredder.

A

We use it on tractor drive, so it's pretty cool uh same components can do everything? That's why, uh with the construction set approach, you get this other 10x factor of cost savings if the parts are truly interchangeable.

A

Okay, yes, we've got that shredder, but now we got. We need to use the second tractor. Well, we could do it put it on a second tractor, so you can have like all this other function based on parts that you reuse, giving you just cost savings, but pending that being easy, like that's the human enterprise part, is you have to make it super simple to disconnect like legos and stuff, like that? That's what we're driving at to the point that technology simply becomes more accessible to more people. That's.

C

All in the gbcs and.

H

C

Product ecology, it seems like electric and hydraulic motors and shafts and couplers.

G

C

Things are like necessary developments for this to truly be an open source.

A

It is like if, at the end of the day, you want to have a ball bearing machine that actually goes down to ball bearings and it's not too hard. That's basically a grinder type of a grinder, but yeah you do have to have those components right now. You struggle a lot with everything being interchangeable, because a lot of things aren't like they're all different.

A

So there is good work to be done if you make more parts interchangeable. So it's easier to maintain the thing it's. The control. Control of the technology goes back into people's hands, the same old same old that you hear me saying, but because there's so much, the standards like standardization is good as long as you don't reduce to to homogeneity.

A

But if you have a construction set approach with a smaller parts, smaller set of parts, you don't go too homogeneity, because you still keep a diverse system because you can make so many configurations.

A

So the construction set approach is for diversity. People sometimes critique saying. Oh well, they'll be just total mass market herd mentality kind of thing happening here, but no, you still retain the construction set aspects which allow you to do more, not less.

G

A

Of 110 items and that's the ultimate construction set there, and this that's where it's going. People will be able to assemble molecules at that level in the future too. So that's a common.

B

A

But it's unevenly distributed.

I

I literally did a workshop a few months ago with a missed on a particle-based active manufacturer, yeah.

A

It's a thing we might think it's so so complicated, but no I mean I mean technology is just crazily uh evolving and then it actually, I think, has implications on that we talked about free will.

A

Well I mean I think that does have implications because then, like all nature versus nurture well, that completely shifts the equation to nurture and change because of what? What, if you could implant a chip in your brain or some biological system that completely changes who you are you can make? That decision is that still self-determination is that still free will you can have the free?

A

Will, I think, to do that to augment yourself, but we know that things aren't the way like if you're born a certain yeah like, I always like to think it's always nurture, because that's just minority model, that's my mental model, how I run my life, but uh you can learn things you can expand and all that.

I

I guess okay yeah, so that's that's a different take on literature and it's a nuance. I didn't quite catch. My conversation yesterday, yeah.

G

Self-Nurturing.

I

As opposed to yeah,.

A

So, let's build some crazy things: okay, where are we on now?

A

Let's nurture some metal.