SLA so far has been pretty much what I expected: really great resolution and detail but it’s more complex dealing with the uncured resin. Post-processing time and especially cleanup is more involved than FFF, so processing 3D prints in batches makes a lot of sense. We haven’t experimented much with different resins, cost of the resin feels like it it is much more than FFF printing, although it’s a difficult comparison since SLA prints use a lot less resin and the uncured resin can be reused if you’re careful.
But oh, what resolution compared to FFF printing! You’re hard pressed to see the height layer lines when printing at 50 microns (yes, that’s .05 mm or .002″) and ours will let us print at 20 microns if you’re willing to take the time. X and Y dimensional resolution is at 75 microns (.075 mm/.03″), which is something you’re not going to see coming out of a filament nozzle printer. Of course for those levels of detail it will take longer to print, although the Digital Light Processing (DLP) system helps make the individual layer printing time much shorter.
There’s some other minor differences, like the way you have to think about supports since the prints are pulled out upside down out of the resin tank. But it’s a nice tool and addition to the makerspace. Stop by sometime & we can show you what we’ve printed. We always have a class in November or December for folks to learn about 3D printing by making holiday ornaments, watch our events webpage or sign up for our newsletter to find out that date and more.
While makerspace folks are all about hacking things, sometimes it’s useful to get someone who makes them for a living involved. Our Rostock 3D printer was an early purchase and with some recent intermittent problems occurring and wanting to do some upgrades, we decided to take it back to the factory in northern Indiana where we bought the kit in 2016 for a tune-up. Besides, we figured it would be a great chance to see some of the latest improvements in 3D printing with a Delta!
We scheduled some time with Steve Wygant at SeeMeCNC in Ligonier IN to look over the makerspace upgraded Rostock Max V3.2 to see if he had some clues about the intermittent problems we were starting to see. If you’ve printed a lot, especially in an environment with multiple people using the machine, you can understand why it’s important to have a 3D printer that just prints. And one where you don’t have to keep tweaking settings to get things printed correctly.
One of the first things we learned: all SD cards are created equal. Ours ended up with a generic card in our Duet controller. Steve had a stack of bad used cards pulled from troubleshooting other printers. After upgrading the Duet firmware to the latest SeeMeCNC configuration, we also installed a PanelDue – an upgrade we’ve wanted to do for a while.
A hotend replacement with an improved connector and resetting the Cura settings/configuration finished the job. And after a month of trouble-free and much improved printing quality, I can truly say the time & trip up there was worth it. It’s really nice to have a printer with online guides and the support behind it to keep it running for over 6 years, plus it still makes prints that people are impressed with. And not having to pitch & buy a new printer when it wears or something goes wrong!
Last Saturday was Field Day for North American amateur radio, an annual ‘open house’ where 40k ham radio operators get out the radio equipment to make contacts and demonstrate to others how it’s done. We’ve helped out the local group PCAUXCOM the last few years by having a project to build or putting on an education session at their location.
We also showed off a prototype satellite tracker that Ian has been designing that was made with 3D printed parts from the makerspace. While it’s still a work-in-progress, the prototype uses data from a satellite tracking app to move a mounted antenna to follow the satellite as it passes the sky overhead. There wasn’t an ISS pass but Ian was able to show how it tracked another satellite during the presentation. The major components were designed in Tinkercad, the same program we use in our Intro to 3D Printing class, and the tracking hardware is moved by software running on a Pi Pico!
This last week I got to do something different during “bring your kid to work day” – provide additional STEM activities for the kids that came to MESH Systems in Carmel, Indiana. The idea came about when a parent in Greencastle, who often brings his child to Castlemakers, wasn’t sure if there would be enough to keep his son interested all day. Since his son really enjoys stopping by the makerspace, and he knew we’ve done many youth programs in the area, he asked if we could do something at his office. After some discussions with their HR person, we were able to put together an afternoon STEM session at Mesh.
There was also interest in 3D printing, so we started with a quick overview of the printing process. After starting our 3D printer making some parts and explaining how some of the 3D printed parts we brought were made, we had them design their own part to be printed using Tinkercad. The later afternoon kids were more interested in design, so we focused in on using Tinkercad to create objects and how it differed from other 3D design programs. Those that were left had access to other 3D printers, so we finished up on how to export and print their designs.
Thanks to Mesh Systems for giving us the opportunity to teach some of their kids about single board computing and 3D printing design!
This Friday night, at Greencastle’s First Friday, we’ll be trying something new, letting folks carve a foam block into a car, then propel them down a wire on Franklin Street.
For the first attempts we’re keeping it simple, although admittedly we’ve got bigger plans. For Friday night we’ve built a platform to put the foam block on, participants can carve the block into a car body, then will launch it down a cable using a CO2 cartridge.
In the future we’re going to try 3D printed and laser-cut wheels & want to also try using model rocket engines for propulsion. We’ve even thought about dual tracks for racing and putting an on-board micro:bit to measure speed and acceleration. Come join us on Friday night from 6-8 pm on Franklin Street in downtown Greencastle and to try out our first prototypes!
One of the makerspace areas upgraded during the pandemic was 3D printing. There’s been several printer upgrades and we even added a new liquid resin printer to the makerspace.
The most significant change has been to our delta 3D printer, upgrading our Rostock Max from v3 to v3.2. That included 3 major upgrades; a new printer controller board, upgrading the stepper motors, and a new hot end.
The controller board change went from an Arduino-based RAMBo v1.3, an 8 bit control board, to a newer 32 bit Duet WiFi board for the printer ‘brain’. The RAMBo board is certainly a good one, we’ll probably use it to build another 3D printer, but the Duet has major improvements in both usability and speed. The Duet is also WiFi remote controlled and since the control board is located internally, the former LCD panel and SD card was removal. We recently bought a PanelDue, so there will be a new touch screen control available soon when we make that upgrade next.
We also changed the 1.5 degree to .9 degree stepper motors. Combined with the Duet control board this reduces the printer noise level dramatically and improves printer quality/speed with the micro-stepping addition. A new hot end assembly also improves the bed leveling sensitivity and heating capability. Bed leveling and the ability to print higher temp materials are a nice improvement for this machine!
There’s been other improvements in makerspace 3D printers, including the Printrbot Metal Simple & an older now modified XYZ printer. We’re in process of setting up a workspace for a MoonRay S100 SLA/DLP 3D printer & will write up more about that in a future post. Come to one of our 3DPO (3D Printer Owner’s) meetups, the next one is 12/30 at 6:30 pm. Or stop by Castlemakers to learn more!
Pointing out the new ping pong ball lamp in the Castlemakers window on Franklin Street is a natural follow-up after writing last month about the micro:bit in the window. It’s a great fun, low cost project built by one of our member with items found at the makerspace, except for the ping pong balls.
Recently several of us started experimenting with ESP32’s, a ‘system on a chip’ device that’s less than $10. I’m working on a squirrel proof bird feeder using an ESP32 with a camera for squirrel recognition, more on that later. This project is built however with an ESP8266 module, predecessor of the ESP32, which cost even less. The ESP8266 modules, bought some time ago for $4, are still quite capable having both wifi and a control channel built in. Ian, who’s known to build things for the heck of it, turned an ESP8266, a bit of leftover led strip lights, some 3D printing, ping pong balls and some glue into a flashy user controlled lamp!
There was mathematics involved in figuring out the right way to spiral the LED strip up the side for tight ping pong ball spacing, which depends on the diameter of the 3D printed cylinder. What’s also impressive is the built in web server. If you’re at the makerspace and logged into our network, type http://pingpong1.local to change the lamp pattern. Pretty darn impressive for a $4 circuit board!
We’re thinking about creating a class to help folks build these. If you’re interested stop by to let us know, post on this blog or send us an email.
One of our more prolific makers, Ian Girvan, recently created a 3D printer using mostly scrap parts found at home and at Castlemakers. It’s impressive, using old computer CD-ROM and DVD drives for their stepper motors and mechanisms along with a second hand computer power supply.
What a great way to learn about 3D printers, brings to mind how the first consumer level 3D printers were created in the early days of the RepRap movement. I’ve been watching in awe the last few months as he figured out how to make the old parts work, only buying a very few new items like the hot end. He’s detailed some of his work for us on this webpage, it’s definitely worth a look!
Some meandering thoughts on successfully building a 3D printer based on old DVD laser head linear movement mechanisms and an old PC power supply:
Greencastle Makerspace has a great selections of 3D printer options (https://castlemakers.org/about-us/equipment/) to allow members and interested members of the public to get hands on experience with this Fuse Deposition Modelling (FDM) additive manufacturing technique. With 3 actual printers to choose from it all with varying sizes and mechanical designs, one might think that as a member, there wouldn’t be much desire for anyone to roll their own. But sometimes as they say, sometimes it’s the journey not the destination that provides the most enjoyment: – or at least the most learning opportunity.
The other activity that has some momentum at the Makerspace in recent months is the addition of CNC capabilities. In addition to the Carbide 3D Nomad, and more recently the Carbide 3D Shapeoko XL, we were gifted a generic 3040 type desktop CNC/router. (http://castlemakers.org/one-persons-trash/) This CNC had the disadvantage of requiring a legacy parallel port from a host computer. All though this could have been arranged, we felt that a better option was to retro fit it with a GRBL controller that has a number of advantages including being able to be used by any of the PCs at the Makerspace and not requiring any drivers of software that is getting progressively outdated. This exercise got me impressed with what has been achieved with open source Gcode parsers and machine controllers with cheap and ubiquitous embedded controllers such as the Arduino range of boards.
In conjunction with this, there seems to be an ever-increasing amount of outdated or superseded technology devices that end up in landfills or otherwise need to be dispose of or (hopefully) recycled/reclaimed to reduce potential environmental impacts.
With this a background in mind, I started wandering around google looking for options to use old commonly available electronic legacy components to create a 3D printer. What I discovered was a good number of examples of people using the head positioning systems from particular CDROM/DVD drives to successfully produce small print volume 3D printers. (To see some of these take a look at the links at the end of the post.) Using this as an inspiration, I decide that I’d get my hands on some DVD drives and see if what I had seen on the internet could be reproduce with minimal financial out lay. To this end I made a trip up to the attic, move the Christmas decorations, luggage and other various totes until I discovered a couple of PCs that had seen better days. A few minutes later I had a couple of potential DVD candidates in hand and returned to start the disassemble. What I found was a little disappointing. I was hoping to see some small 4 wire stepper motors combined with small carriage on rails carries the laser heads, all driven via a small diameter lead screw. What I found was the later models that used a standard (and no doubt cheaper) standard DC motors.
Back to the search.
A quick review of the computer hardware in the Makerspace, came up with 3 potential candidates and with the luck of the Makerspace, they all had stepper motor-based mechanisms. The basis of the 3-axis movement was in hand: – time to “glue” it together in some fashion.
Framing Things Up
In my Google travels I came across a design for a laser cut frame for this type of printer. Give the Voccell laser (https://castlemakers.org/about-us/equipment/ )is another one of the tools at the space I decided I’d make a couple of adjustments and press that laser into action to produce a plywood frame.
The Hot Stuff
One of the key pieces of a FDM 3D printing process is the hotend mechanism to heat up and extrude the filament on the bed or build plate. Also to ensure the initials layers of filament stick to the bed, the use of heated bed is often used and allows printing materials that would otherwise be challenging to get to effectively adhere.
The examples I found online of printers built at this scale didn’t use a heated beds but rather focused on limiting the materials printed to those that would allow unheated beds like PLA. I thought it would be interesting to include bed heating to potentially allow using more varied material. A small scrap of 50mm x 50mm 1/8″ thick aluminium was used as the bed. 2 1 ohm 7W wire wound resistors were attached to the bottom of the bed with high temperature JB Weld.
The resistors were connected in series and some tests run to see if the bed could be effectively heated with this arrangement. The tests were positive and this bed was attached to one of the DVD mechanisms in place of the laser head.
When looking at options for the hotend, it became clear that building a hotend from scratch, although fun (perhaps another blog post in the future) would probably not be within the spirit of keeping the over build time within realistic limits. As it turns out, eBay provides a large number of relatively cheap hotends with the necessary heater elements, temperature sensor, nozzle, cooling fans etc ready to go. I was able to purchase an E3D style hotend for under $10 shipped. I decide to go with this approach for now and leave the option to build my own for the future challenge.
Bowden Tubes and Extruders
Because of the very small motors that make up the DVD mechanisms I estimated that they simply would not be able to carry the weight of a direct drive extruder so it was an easy decision to look at a remote extruder with a Bowden tube to guide the filament to the head. This also factored into the selection of the e3d hotend.
Having manually pushed filament into a hot extruder it was clear that more power would be needed from a motor than was available in a DVD drive.
The standard for the consumer class extruders is to use a nema17 standard motor of around the 1-2 amp phase current. Back before we had CDROMs there were 5-1/4″ floppy disk drives and they often used nema17 stepper motors to move the heads. It may be showing my age, but I did harvest a few of these motors before disposing of them. Unfortunately, they are of the unipolar variety rather than bipolar which most common current stepper driver electronics are set up to work with. It turns out these motors can be purchased on eBay for less than $10. As fortune would have it, an eBay seller known to the Makerspace has an online store and provide a number of parts with no shipping overhead. This included the aluminum extruder itself. All up the extruder, motor and pfte Bowden tube came it at ???
We’ve still had projects at Castlemakers this summer, even with the Covid shutdown hampering our hands-on education efforts. One that I’m excited/impressed with is a high school student built project that includes programming, electronics, 3D printing and using a laser cutter – all made with items at the Makerspace!
Ever since we gave every 6th grader in Putnam County a micro:bit last year, we’ve wanted to do more micro:bit projects to help youth and adults see the power of microprocessors and IoT devices. And to get a chance to expose and use some of the some different fabrication tools often found in a makerspace. This summer Hunter Miller made a really interesting project, an edge lit sign controlled by a micro:bit. It looks a bit like an emergency exit sign with a disco like effect and instead our logo on it.
The design and case was modified from something created at the Cambridge UK makerspace, who was looking to create something to experience the different makerspace tools. We used our 50W CO2 laser to cut and etch an insert for a 3D printed case that with led lighting on the edge makes our logo stand out. Hunter, who was looking for something else to do this summer, then cut a section of a 2m LED strip and after some soldering connected the wires directly to a micro:bit. Then he wrote a micro:bit program using MakeCode that makes the LED strip change color and intensity.
It’s on display right now in our front window on Franklin St. Stop by and take a look or come in and we’ll show you how it works – the different lighting modes may have you dancing!