• aditya mehrotra.

3d printer upgrades: getting our printer to do a little more [updates]

So today I want to spend a little time upgrading the printer through what we think is the most important upgrade we can give it - a housing. Later we'll upgrade the housing to look at the print and automatically stop it if something is wrong but that's not a now problem. The reason we're giving it an insulated housing is because when printing PLA and Carbon PLA, these filaments don't warp so much so having the heat escape from the build-plate to the environment or having the filament cool quickly isn't really a problem. But when printing Nylon, ABS, etc, the warping of the filament due to quick cooling tends to make the part itself very warped and then it is much more likely to peel off the build-plate: https://prototypeinfo.com/standard-3d-printer-enclosures-uses/



But the problem with just getting one of these is they're expensive. So we want to make our own out of things we can get at home depot - simple and not too expensive. A case about the size we were looking at is something like this : https://www.3dupfitters.com/products/creality-crx-acrylic-enclosure-case-kit?variant=29232664674346&currency=USD&utm_medium=product_sync&utm_source=google&utm_content=sag_organic&utm_campaign=sag_organic&gclid=Cj0KCQjwvIT5BRCqARIsAAwwD-TYZoKfLujqyjuAoDoQk_rDAkzH0f7O4WZ_tNJ7Q6KvOe8R68_t0vwaAlqyEALw_wcB which is around 400 dollars each and is made of acrylic. So it was time to take a trip to Home Depot.


At Home Depot we found the following things:

After seeing these, a plan started forming as this was a much a much cheaper solution to the plastic panels/polycarb panels that were sitting on the shelf. Something like this:



Please note that this CAD was made after the thing was actually put together. But when you have four glass sheets, two pieces of wood, and some hinges, there aren't that many ways we can put them together. We decided to go with VHB tape to connect the panels to the wood for now and here's the result:



First we unwrapped the 3/32 glass panels. They're really sharp so I think we're going to go on Amazon and actually get some real glass protective edges so we don't cut ourselves.



Take that 2x4ft piece of wood and cut it in half to make two 2x2ft pieces of wood which will form the top and the bottom.



Then we started VHB taping on the glass panels the first two were done together so nothing fell apart. If re-done we might do this with GLUE and not VHB tape because I don't know how long the tape will last on the wood but we'll find out for sure!



That's the rest of the panels in and while this thing could support itself we grabbed two piece of wood supports and stuck them inside - mostly because we really didn't want to find out if the glass could hold the weight or not.



Little crooked - but we'll fix that when we actually glue them in :)



Now it came time for the hinges as well as some weather stripping around the printer for now just so we could protect our fingers. The actual stripping is coming on Thursday.



Printer inside, door on, and a handle made from the filament spool holder which wouldn't fit in the casing. We don't want it anyways since we don't want the filament spool inside the 3D printing case.


We're going to name this guy Phobos. As at some point we'll make a twin called Demios which will be a grinder/extruder/winder for filament that lets us be nicer to the polar bears and the planet (that was the idea for filament labs ONE. Which we'll talk about in a second. We'll get better pictures of this guy up later. And we'll run tests to figure out really what the build/print quality of the printer now is as compared to before.



NOW MORE IMPORTANTLY:

Now remember a while back we talked about Filament Labs? And possibly creating a solution for 3D printing from recycled waste? I want to revisit this idea. The thing is this. We need to figure out, before we start trying to build a solution, how exactly we'd plan to solve a problem like plastic pollution and there are many ways to do so. One approach is here: https://community.preciousplastic.com/academy/build/shredder


Precious Plastics is an effort started by someone to help re-use plastic around the world. The idea is to provide people with the tools to start their own plastic for-profit business which is a fantastic idea in my opinion. So basically how it works is you can be a collector and supply to a local shredder, you could be a shredder which shreds and supplies to makerspaces and manufacturers, and then the manufacturers can produce something with the shredded/recycled plastic.



This is the idea of precious plastics - so what I'm proposing isn't simply just something that can start one of these hubs. I'm talking about working with precious plastics to expand this ecosystem.


Filament Labs would work as a member of the precious plastic ecosystem and do a few things:

  • ONE: Organize cleanups in the area including beach, river, park cleanups and etc. Volunteers would wash the plastic and remove the labels and etc. We would also sort the plastic into different types.

  • TWO: We could supply these to a local precious plastic shredder, or in areas that don't have that community, Filament Labs would be a hub that shreds and recycles the plastic.

  • THREE: Any plastic we then receive and shred ourselves, or in places where we can receive plastic from a shredder, we would turn into 3D printer filament and sell them to schools, universities, and people for a discounted price.

  • FOUR: We would make tools that allows people to shred and extrude their own filament, open source, but very cheap so people can do what precious plastic is doing but in a much smaller scale (within a Lab or a home instead of within a whole community).

  • FIVE: For universities that want to discard 3D prints and excess filament and etc after its been used or a project has been finished. WE can setup those collection programs as well and the cycle re-starts.

So what Filament Labs would do is basically operate in the areas where precious plastic does not to expand the reach of the precious plastics project. And in areas where precious plastic's idea has not been introduced, we would work on starting that community.



So that's the idea behind filament labs now. Not as something that could be a competitor to this amazing project that already exist, but something that can work within that ecosystem to expand it and help us recycle more and more plastic. So here are things we, as a company, want to develop in terms of engineering solutions to problems.

  • A Machine that can extrude and wind filament very inexpensively.

  • And possibly a 3D printer that can print this filament really really well with an enclosure and everything.

  • If you buy our 3D printer then you get a discount on the filament for life or something as an incentive. And we will make all kinds of filament.

This is what filament labs could be. It doesn't matter if someone is already doing these things we can fill the gaps in what they're doing and help build a bigger community for plastic recycling. So what we're going to do is try to develop a really cheap filament extruder kit that people can buy at cost or build at cost for like <$200 but something that's really really easy to make. Most solutions right now are HARD TO PUT TOGETHER and EXPENSIVE so we need to do better.



So here's a simple case we can make for the product that would cost us in total about, 25+11+11+4 = 50 wish dollars? And this forms the frame and the casing for the whole product, let's throw in a roll of VHB tape.

https://www.homedepot.com/p/Everbilt-4-in-x-4-in-Oil-Rubbed-Bronze-Square-Corner-Door-Hinge-15015/202558096 already have one of these just need to grab a second.


https://www.homedepot.com/p/3M-Scotch-1-in-x-11-1-yds-Permanent-Double-Sided-Extreme-Mounting-Tape-414-LONGDC/205507375 that's another 20 dollars.


https://www.amazon.com/Irwin-Tools-304300-WeldTec-Auger/dp/B002WJTV0W/ref=sr_1_2?dchild=1&keywords=Irwin+auger&qid=1596037650&sr=8-2 this was 22 dollars and now we're up to 100. So we need to do everything else in <100-150 dollars to make this a really nicely-priced product.


https://www.amazon.com/Aobbmok-70RPM-Torque-Turbine-Reducer/dp/B07DYRDXYX/ref=sr_1_29?dchild=1&keywords=70rpm+dc+gear+motor&qid=1596037793&sr=8-29 let's say we get a gear motor with this output so that runs us an extra 30-50 dollars. That's 50-100 dollars for the rest of the electronics.


Now the filastruder is: https://www.filastruder.com/products/filastruder-kit is 299.99 so if we can't get it under this with a winder none of this makes sense. OR we need to make it smarter somehow. We can also look into a fully mechanical winder. That would be kind of cool. Mechanical winding/cooling. At some point maybe we want to put a grinder at the top but not right this second that would probably bring it up to 300 dollars but thing about it. 300 for a winder, grinder, and extruder is really good. We need to 3D print some parts for this and then get a few other things. We're not going to add the grinder right this second but we should plan for it. So it'd look something like this:


Now if all of this was like 300-400 dollars that's a really good price compared to what's out there right now. And we want to promote making this easy, and all-in-one solution.


What were the problems with the last version?

  • The barrel was too large in diameter, the auger did not sit very snugly inside the barrel of the system.

  • Too much of the barrel was heated only the front part should have been heated to make this easier on the motor.

  • Let's maybe not with the bang-bang control?

For now, I think we'll use our touchscreen and the Jetson Nano, when it's a product it would definitely change to something else - that one's too expensive. So let's first talk about what we have at home.

  • ONE: the auger itself

  • TWO: the wire we need to make everything hot (nichrome wire)

  • THREE: the motor controller, the thermistors, and the arduino and touchscreen as well as the jetson nano

  • FOUR: Insulation and etc.

So we NEED: The right sized pipe, a power supply, and the stuff to make a study case and then just to actually do it right? I don't think anything else is left. Note we aren't making the grinder right now.


Might be time for another short trip to Home Depot :)) - our glass panels are not in stock so there's no point picking up the VHB tape or anything else. But we can go get one piece of wood and start working on the rest of the system! We wouldn't want to put the glass on right now anyways. https://docs.google.com/spreadsheets/d/1Lh4LP3ZWDAw1VITRh-nhRhNX3j5vTii0vxzPC0tpvK0/edit#gid=0 This sheet includes only things that have been placed on the product itself - not development costs or anything.


So let's make that home depot list:

  • (1x) of the those Wood Boards

  • (1x) of that long "V" shaped channel that we can use to direct the filament after it's been extruder

  • (1x) pipe and cap we can use that fits the auger itself

  • (1x) roll of VHB, (1x) roll of kapton tape

What we ended up getting was just the board and the V-shape channel for the filament winder/cooler. There would be only one or two things left we'd need to get from Amazon. We need to get the gear motor and some other things.


https://smile.amazon.com/dp/B07BWBQXLF/ref=sspa_dk_detail_2?pd_rd_i=B0774HGZGX&pd_rd_w=Q4i3Z&pf_rd_p=48d372c1-f7e1-4b8b-9d02-4bd86f5158c5&pd_rd_wg=2UWC5&pf_rd_r=9MDNXAX7GFC45XGC6KG4&pd_rd_r=3b9dfc23-0f6e-4ae1-918f-81e88f2fefb2&spLa=ZW5jcnlwdGVkUXVhbGlmaWVyPUEyVFFSUDJQQzJEUllFJmVuY3J5cHRlZElkPUEwOTY2Njc1M0NNTUlESTVQMFVTTyZlbmNyeXB0ZWRBZElkPUEwNzA4ODc5M0taUDVXNkpJMlhUOSZ3aWRnZXROYW1lPXNwX2RldGFpbCZhY3Rpb249Y2xpY2tSZWRpcmVjdCZkb05vdExvZ0NsaWNrPXRydWU&th=1 this motor has 7 times the torque that the previous motor did. At the moment, we aren't going to use an encoder. Just straight voltage control it will do around 16RPM when we give it full beans. And it's rated for 70kgcm which is like 7Nm. We're going to use Kivy, the Jetson Nano, and that system to control our filament extruder instead of the Arduino because then we can make a touchscreen GUI. From tomorrow we can start the CAD on the individual parts and printing things like the housing or the coupler for the gear motor to the actual shaft. Remember to account for 0.003" tolerance and then shrinkage of the part.



So we have some WOOD filament we would love to use to print some parts for the Filament Extruder. That includes parts like the case of the Jetson, the mount for the thing and etc. For now we won't be drilling a hole in the top to actually put the plastic in we'll do everything else we need include design and install the touchscreen, the hopper, the parts for the extruder and etc. We really want to 3D print as little as possible, use as much wood as possible at the moment because it's cheap and easy to work with and we have a lot of it.

If we look at this diagram and compare it to how we constructed the extruder last time, we'll notice the agues doesn't go as far as we thought it did. And in-fact we really need some space at the end of the barrel - the melting chamber - before the whole things hits the nozzle.

And we need to leave like 36+15mm for the motor system so let's make that like 55mm for some clearance. Let's mark that out. So the rest of the interior framing we're going to try to make out of a SINGLE 2x4x96in stud wood. Then we drill a 1" hole in the middle and start mounting things to it.


Now the question is how hot do we want this thing to get - let's say 300deg C. And we have 28 gauge nichrome wire - how long a wire do we need if we're powering it with 120V AC.

So let's say we power with 12V, and we want to give the thing 1.55A to get it to 316degC. That means the wire needs to have a total resistance of 20 ohms. Which for this wire is... 4.0875 Ohms/ft which means 4.55 feet! So a lot less than what we have been using. This will get the system to work at 12V DC and not 120V AC. Which should help some things. We'll also need to get a 12V power supply at some point for this but let's measure out those 4.5 feet of wire. So we measured out 4ft 7in just for safety and now we know that 1.55A - 1.18A will give us the temp we want at 12V. We can actually hook this and the motor both up to an L298N probably. Let's check the current rating on the motor and the L298N. So the L298N is max 2A per channel but this works for the Nichrome Wire and it might be more reliable than relay. And the motor we got is rated for (rated current-1.6A)! Which means two L298Ns should be able to control the motor driver as well as the nichrome wire. Why is this working out so well :)!

So these are the things we would get to finish this thing off but I don't think we're going to buy them right now because we have substitutes lying around that will work in the same way. (Except the filament we might need to get some of that).


We're currently trying to replace our 3D printer nozzle with the 0.8mm again just so we can like use the wood PLA because that's pretty strong stuff - it's flexes instead of breaks which is Nice and then we'll go print parts like the Jetson case and the shaft collar and etc while we're assembling the rest of the structure.



So we're going to hold out on the rest of this until the rest of the needed parts show up on Saturday/Sunday. For now we've made some good initial progress.


#updates #omgrobots

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