PrawnTech3D Lives Here!

( - responsible plastic)

Beyond just plastic

(This is now a big but mostly finished - and hard to digest in one sitting - page. Take your time...)

Getting harder:

As you've no doubt seen in your web travels, some plastics are very forgiving of temperatures:

PLA is one such that has both a wide range of usable melting temperatures, and also the material itself is made 
with a fairly wide range of melting temperatures and Tg. (glass transition Temperature.) This means that a (for 
example) PLA filament from Brand A is easier to print with at 185C while another needs to be printed at 200C. 

And with some plastics, those ranges are quite narrow and specific.And if you melt some at a slightly higher or lower temperature, the resulting melt has different properties. Not always desirable properties (think: brittle chalky powdery, bubbled / splattered, etc) but sometimes all you're looking for is a slightly harder product and then maybe the altering exact temperature makes sense.

Check HERE for a few of just the 3D printing filaments and know that there are literally thousands more formulations out there.

And speaking of "bubbled / splattered" as we just were: the troubles with PET and nylon are extreme example of hydroscopic plastics, that is, they absorb moisture. That means not just from being immersed in water, but - especially - from humidity in the air. PETG (the "G" is an additive specifically added to make it print better, but it's just PET plastic when you come down to it) in particular is famous in 3D printing circles for this. 

The answer in 3D printing ("FDM" or "FFF" additive manufacturing) circles has always been to cook the plastic for a few hours before using, thus driving off the moisrture. With nylon (PA) in particular, it's worth noting that the FFF community has seen cases of a dry PA filament exhibiting moisture symptoms towards the end of a large print. Their answer to this has been to place the filament spool into a climate controlled box and feed it out to the printer through a tiny exit opening. 

Also of note is that in some cases, it's necessary for a plastic to absorb moisture. Check out your nylon strimmer line sometime. Many warn you to allow the trimmer line to have time to absorb moisture from the air before using as otherwise it's too prone to shattering. This is a case where moisture is necessary. 

PROTIP: Perhaps if bottle manufacturers could be tempted to switch to PETG for bottles, then such bottles would be recycled into filament at a much higher rate, diverting them from landfill for several cycles. (Also note that the "virgin plastic" trope applies here, for every PET/PETG bottle or spool of PET/PETG filament we recycle, that's one less NEW bit of plastic that has to be created from petrochemicals..)

PROTIP: Also note that with solar PE (photo electric) coming down in cost all the time, and therefore the cost of heating and pumping / shaping plastic creates less and less of an environmental footprint, and we need to stop thinking of energy as a limited resource. All manner of new processes are going to be developed for clean energy production, and we HAVE to think of ways of using this energy rather than more traditional methods.

And harder yet:

It's easy to recycle aluminium - provided you have free and clean energy (Oh - see the last ProTi P above - Yayyy for vertical and horizontal thinking!) then you can make small induction forges to melt aluminium which can then be used for making dies for injection molding. The best part? You can (these days, very easily, it's built into some variants of the software) 3D print a mold of the item you want to make, mold that in sand, then use the sand to cast as many molds as you want for distributing around the world to other PreshPlast or similar Hubs. 

What I'm saying is that while we once thought in terms of doing things like molds one by one and needing to buy new materials and watch our energy budget, by adopting HUGE solar PV arrays and batteries, we can do things that once needed a factory to do. As a bonus, those solar installations in developing countries can supply energy to the surrounding places by providing charging stations for electric cargo bikes, other batteries, and USB devices. (We could also be the people MAKING those electric cargo bikes, hint hint. (And also see the next section, hmmm what can it be?) These are great directions to take a Hub and a dman sight better than those &*(^T%^!!! O Bikes and similar schemes that waste hundreds of million dollars between them, as well as millions of tonnes of precious materials that are now piled up several stories high around the world.

OPEN TASK: Someone with more skill in negotiating with large corporations that are desperate to establish their green credentials needs to speak to places like Tesla and ask them to support PreshPlast with solar roofs and battery banks / inverter systems. I mention Tesla because with their offer to put a peak load battery into South Australia a few years ago they proved themselves to have a viable large energy solution and also as leaders in the field. Other companies doing this, I can think of Neoen France right off the top of my head and there are by now literally HUNDREDS of companies offering solar / battery / inverter solutions, maybe some of them could be convinced to develop a "container solution" to compete with conventional internal combustion engined generators. Hmmm... Maybe this is another thing WE could develop and open source? That would create competition, which would create lower prices, which woul . . . Hmmm...

The thing is, PreshPlast machines are designed to be frugal on energy, so transitioning to renewable / battery power is easy. But because we see our projects ending up in underdeveloped places, we tend subconsciously to keep thinking in terms of energy poverty. Once you have the idea of practically free energy firmly ensconced in your scone, magic is possible. 

Things become possible.

I think I've already mentioned induction heating. Induction cooktops are great for food preparation, boiling water for plastic cleaning, etc. Once you acept the idea of almost limitless free energy, many new ideas become less crazy and more possible. So using an induction cooktop as your source of clean free hot water for washing is possible. Developing plastic washing and cleaning processes that aren't constrained by the need to be frugal with energy is possible. (And of course I don't advocate going batshit crazy with energy, but just to realise that instead of using a difficult bulky sledge hammer to crack walnuts it's now possible to have a small electric machine that can do the job faster easier cleaner and with less waste of effort.)

Then as mentioned there are induction furnaces for metals and some other materials. And straight-up electrically-heated furnaces for glass and ceramics. Even microwaves can be useful in some circumstances. 

Economy of scale fallacy:

Back for a moment to that energy economy.

A small scale operation for recycling glass locally using a small electric furnace is quite do-able. On the other hand, if you wanted to make a large glass recycling plant you'd need to buy electricity from the grid, hire technicians to maintain things. You could save on artisan wages by tieing one poor glass artist down to a contract, but your major cost would be the energy. For us, the opposite can become true - we can generate the electricity cheap or (once amortised) free, and have a dozen artisans working with the product. 

Working with other existing technologies:

Food dehydrating / room dehumidifyingtechnology:

The 3D printing community have long embraced the use of food dehydrators for drying off plastic filaments. A dehydrator base makes a nice slow (and generally lower than 500W power consumption - nice!) power unit for a drying process. Combine this with Peltier devices to condense the water and you have TWO usable products - dry plastic for further processing, and de-mineralised water for other processes. (And yes, there are VOCs when heating plastics but their release is minimal under dehydrating temperatures and in any case they won't somehow magically get into the water except under a combination of bad luck, bad machine design, and operator error.) As a further benefit, by using a fan roi recirculate the hot air off the other side of the peltier devices, you recycle that energy back into the dehydrator. MAGIC is possible at such small scales. (In a large scale plastic drying plant, you'd be stuck with using a refrigeration plant to condense the moisture out of the system. Such is the magic of small scale local operating...)

The 3D Printing (FDM/FFF) Technology: 

3D printing is now quite mature. With proper attention to the details and selection of materials, commercial quality results are possible. ALSO POSSIBLE are the 'adoption' of parts of the technology to processes. By a bit more attention to the design of those beam extruders, it should be possible to 'continuously' extrude (say) 2.4m beams, smooth perfect beams cut to industry standard lengths - without any more human intervention than monitoring the process from time to time, adding more material to the hopper, and clearing a pile of finished beams every few hours.

The GigaBot X is a machine suited to becoming a starting point for designs. From there we can actually move to something a bit less conventional, combining large format, multi-material, speedy, and capable of real-world applications such as the SUEVs (Small Utility Electric Vehicles) I'm proposing for under-developed locations. The hope is that first world governments also get the stick out of their backsides about small urban electric bikes and tiny trucks etc and realise that these are cleaner, cheaper, and better for all environments than ICEVs. (Internal Combustion Engine Vehicles.)

With regard to the clumsy heavy SUEVs I've seen, it's possible to manufacture bodies and frames using 3DFFF techniques such as making hollow panels reinforced with 'infill' which is a pattern similar to the honeycomb used by manufacters already - but better - and with minor tweaks it can be printed such that there are spaces for wiring and latch assemblies, hinges, etc. 

Imagine an idea. An open source system which lets any village to set up solar panels, battery energy storage, and manufacturing capabilities to produce materials and equipment needed in their location - including transportation and mobile machinery. (You know that this is beginning to approach the idea of a self-powered mobile facility that just traverses countries leaving new facilities in its wake. Not quite achievable yet but it could happen. The "PreshPlast Travelling Circus" comes to a town and that town is changed forever for the better.)

OPEN TASK: Someone familiar with vehicle standards, electric vehicles in particular, government lobbying, petitions, and activism to get laws chenged for small utility EVs, to do all / any of the above, help us design a safe vehicle, and help it get across the legal line as many countries as possible. 

Another idea: Using roller forming for plastic sheets. It's a repeatable process for metals already and could be scaled down and adpated for the plate press idea, and it could even be adapted to making more or less continuous sheets. Combined with wooden frames you can have yet another modular system for tiny and emergency housing, workshop welding screens, etc. 

Another one: One can buy '3D pens' now that use existing 3DFFF filaments. They're nowadays also used for plastic welding and repairs, and aren't all that hard to replicate, they're all known and fairlyt common technology. Combine such in-house-made plastic-welding pens with the making of the SUEVs and you have the beginnings of strong, safe, reliable SUEV technology.

Harder again, but do-able, or at least, imaginable:

In fairly broad brush strokes, here's some really out-there ideas:

Once you have: Cheap energy. Cheap manufacturing processes for a variety of products. And some resources to try things out. 
  • You can try to build systems to take the grunt out of the grunt work. Some recycling processes can only be done by humans at the moment. Removing contaminants from plastics, as in labels, dirt, glues, etc. If this can be automated given that we would by then have cast (and possibly also rolled, see up a few paragraphs) aluminium and plastics. 
  • You can see if an arrangement can be struck with the organisatyions currently stuck with the three storey high mountains of O Bikes and similar 'app to ride' bikes. Look - bikes are the answer, and piles of these hi-tech treadlies sitting as landfill separator columns are useless to everyone and everything. They need to be out and performing valuable jobs. Ticking time-bomb moment: Each of them has a Li-ion battery inside to power the electronics. One day those batrteries are going to poison the immediate surroundings and who knows how far that'll be given wind and water as well? Opportune moment: Realising that they have electronics inside as well! And THAT is another resource, they contain at the very least a bluetooth or GSM communications device, some kind of locking mechanism. and possibly a GPS as well. I could break that out for you but think: At least a low power consumption means of monitoring crops paddock livestock pens weather (and there are literally hundreds of thousand of these rotting away) or connecting a village to the GSM network or their local PreshPlast Hub for whatever needs. A way to pretty precisely locate resources, a way to make SUEVs that can be3 community owned and operated at a level where they're appreciated rather than abused. And if someone can be bothered to sit and test each system, a product you could put on the Bazar for people in cities to lock, secure, and locate their personsal bicycle. Lastly, a resource for yet another project I've dreamed up. (More on this on another page I think. This page is already a big thing to digest.)
  • Recycling other equipment and machinery. (This too is part of Project RCX: The Next Steps alluded to above.) Bear in mind that very soon there are going to be EV batteries getting thrown out by unscrupulous 'recyclers' and they really need to be taken out of thew environment and re-purposed or broken down to the point where a more complex facility can recycle them. 

But we can have plastics, glass, aluminium, some limited electronics, and who knows what other treasures every bit as valuable to One Army as plastics have been to PP.  And as a (rather HUGE benefit) we're saving the planet one recycle stream at a time.