(NaturalNews) I spent most of the holiday working on 3D printer designs and calibrations, and I’ve learned a tremendous amount that I’d like to share with you. This is all very practical information you’ll need to have for the upcoming launch of www.FoodRising.org where I’ll be posting open source downloadable 3D printer files that you can print on your own 3D printer.
The biggest realization so far is that the Lulzbot TAZ 4 printer is not working with the filaments needed to produce these functional, water-tight objects. This is a disappointment because I love the Lulzbot company’s open source philosophy and overall sense of innovation and optimism. I’m optimistic that their new Lulzbot Mini — coming out in February — will overcome the filament feed problems I’ve experienced with the TAZ 4, and I will of course purchase one of the Minis and review it as soon as possible.
The photo below shows the filament jam problem that happens when feeding either Colorfabb XT or t-glase filament into the TAZ 4. At first, I thought I had this solved by installing a second fan to cool the extruder and prevent so-called “heat creep” from melting the filament. But even this second fan only worked part of the time.
In fairness to the Lulzbot company, the TAZ 4 printer was really designed to print PLA and ABS, both of which it handles quite nicely. These newer filaments — Colorfabb XT and t-glase — came onto the market long after the TAZ 4 was ever designed. Colorfabb XT, in particular, requires a higher print temperature than what the TAZ 4 can really support. (It likes to print at 250C, but the TAZ 4 tops out at about 238C.) The new Lulzbot Mini reportedly supports hot end temperatures up to 300C!
This photo shows the “heat creep” filament jamming problem that occurs in the Lulzbot TAZ 4 when you try to print Colorfabb XT (the white filament) or t-glase (the green). I’m confident this problem has already been solved for the new upcoming Lulzbot Mini, which I’m really excited to try:
And this photo shows the disassembly and cleaning of the TAZ 4 extruder:
FlashForge 3D Printer working great with zero problems so far
Searching hard for something that could print Colorfabb XT and t-glase filament, I bought this FlashForge 3D printer from Amazon.
You can read my Amazon review of this printer at this link.
The first thing I noticed when I received the FlashForge 3D printer was the robustness of the extruder. The extrusion head, cooling fins and fans all seemed really rugged. I purchased some Colorfabb XT filament at 1.75mm (that’s the diameter used by the FlashForge) and fed it in using the auto-feed option.
Today, about a week later and after completing probably a hundred small prototype prints, I have not had a single filament feed problem or jam using Colorfabb XT. This is extremely important to note because it means I can start a print and walk away from it without having to fret over what might happen to the filament. In fact, I’ve been able to start a long print before going to sleep and then wake up the next morning with the completed object looking great.
The Colorfabb filament, however, turned out to suffer a problem all by itself: It doesn’t print water-tight objects. I discovered this the hard way after wondering why water was leaking out of the objects printed with Colorfabb XT. It turns out the filament just doesn’t fuse together as well as t-glase. (More on that in a follow up article.) Or, possibly, I need to run it at a much higher temperature such as 265C which most printers don’t yet support…
T-glase filament in the FlashForge
T-glase filament prints well in the FlashForge. You have to slow it way down on the first layer, of course. I’m printing really slowly, at 20 – 30 mm/s with a speed reduction down to about 40% for the first layer. This is working well, but it’s not speedy.
I did discover one issue with t-glase filament that I was able to troubleshoot. The FlashForge filament loading utility does not pre-heat the extruder heat to a sufficient heat for t-glase filament. So to load t-glase reliably, what you need to do is pre-heat the extruder head to 240C – 250C, then run the filament loading utility before the extruder temperature drops.
Similarly, if you’re printing with t-glase and you hear a “thumping” sound during the print, this is an indication the filament feeder is slipping because you don’t have the heat turned up enough (the filament is not “soft” enough to easily feed through the 0.4mm nozzle). You might experience this problem if you try to print t-glase at anything less than 240C. You’ll have far better success printing at 240C or even 245C, where the filament is soft enough to be pushed through the extruder at the expected rate. I suffered a couple of ruined prints before I finally figured out this was a temperature issue.
The Dremel 3D printer appears to be a FlashForge
The good news in this is that the FlashForge Creator Pro I’ve been using is performing quite reliably so far, and although I don’t have a Dremel unit, chances are it’s based on the same hardware and manufacturing process, which means it’s probably reliable, too. The only potential limitation is the 230C print temperature of the Dremel unit. This 230C will likely not be hot enough to reliably print t-glase or Colorfabb XT. It will work fine for PLA and ABS, however, but neither of those filaments are suitable for the projects I’ll be announcing at www.FoodRising.org (I will announce my official filament recommendation soon).
I’m really excited the Dremel company has the vision to jump into the 3D printing market, and there’s no question that the objects I’m about to release on www.FoodRising.org will spur lots and lots of sales of various 3D printers. The Home Depot even carries the Dremel unit, so this is a sign that 3D printing is really going mainstream.
The Dremel has a 100 micron build resolution, which simply means 0.1mm layer height. You won’t even need this precision on the Z-axis, since you’ll be printing at 0.3mm layers with my designs. (Which is far faster to print anyway, and has far fewer problems with first layer bed adhesion.)
By the way, don’t be distracted by 100 micron claims of accuracy across 3D printers. The truth is that none of the 3D printers have 100 micron accuracy along the X and Y axes. They only have this accuracy on the Z-axis (vertical). So if you think you’re going to design a perfect sphere that has 100-micro accuracy all around its surface, think again… it’s not possible with today’s consumer-grade 3D printing technology. This is why many of the parts I’m designing are so difficult to design: the geometry is daunting when considering the limitations of today’s 3D printers. Just making parts that fit together snugly is quite a challenge all by itself.
Recommended FlashForge 3D printer settings
The FlashForge Creator Pro printer has a 0.4mm nozzle, which is more precise than the 0.5mm nozzles on many 3D printers. For this reason, I am currently running the following settings with very good results:
TIP: You can use a #9 metric socket to remove one of the extruders from the dual-head FlashForge. This will get it out of the way so it doesn’t scrape your 3D object while the other head is printing.
Layer Height = 0.3mm (no, don’t think you’ll get better prints at 0.2mm or 0.1mm, it doesn’t actually work out that way. The 0.3mm filament bead is more reliable. I’ve tried all the layer heights and 0.3mm is the best by far when you’re using a 0.4mm nozzle.)
Extruder temperature = 250C when printing Colorfabb XT or 240C for t-glase. The FlashForge company told me not to exceed 250C or I might melt the PFTE tube inside the extruder head. (I did actually melt one, come to think of it…)
Print speed = 20mm/s to 30mm/s. Yes, you have to slow these down due to the geometry of the parts I’ll be sharing with you soon. Many of these parts have inside negative space cylinders, and if you try to run those at high speed, you’ll get unintentional string bridging across the negative space. Those have to be printed at 20mm/s.
Infill = 100%. Yes, 100% because many of these objects have to be water tight. Some of the objects (I’ll note each one) can be printed at 20% infill.
Infill overlap = 70%. Yes, this seems high, but remember we have to close all the gaps in the object to prevent water from leaking out.
Retraction = 3.5mm – 4.0mm.
Shells = 4. You need to run 4 solid layers on top and bottom, plus a 4-layer shell thickness. Yes, this seems excessive but again we are trying to achieve water tight geometry here, so the 4 shell layers are needed.
Bed adhesion = Elmer’s purple glue on top of Kapton tape works great. For smaller objects, I’m even getting good results without using the glue at all. T-glase has very little shrinkage, unlike ABS.
With these settings, it’s going to seem like your print head is moving very slowly. But remember that you are churning out 0.3mm layer height which is thick. This means your total print time is a lot less than you might imagine. I have tried all sorts of variations on all these parameters, and I’ve found that the best output is achieved with the thick layer height combined with a slow print speed and a hot extruder. Essentially, you want to lay it on the bed HOT and THICK and SLOW, and don’t make any kinky jokes as I’m describing this, you deviant!
Don’t try this at home: If your 3D object gets knocked off the plate during the print and you let it keep printing, here’s what you get: MODERN ART!
Extruders allow you to make your own filament by recycling previous prints. For some filaments such as t-glase, you can even use up to 12% water bottles and milk jugs. Yep, you can turn trash into useful objects through the combination of an extruder and a 3D printer.
I’m currently awaiting the arrival of the EB2 Extrusion Bot shown here:
Once I receive this, I’ll get it up and running and share the results with you. I purchased it with the grinder, too, so I can chuck water bottles into the mix and see what happens. Now all I have to do is run around town and do a little dumpster diving to find some water bottles. Fortunately, they seem to be everywhere…
My main question is whether this consumer-grade extruder can produce filament at a consistent diameter. The diameter of the filament is absolutely crucial to reliable printing, especially when we’re talking about parts that need to fit together and be water tight. Fortunately, I have the microscope in the lab that I can also use for a close-up visual inspection of filament tolerances. A good set of extremely accurate calipers also comes in handy.
Sign up now at www.FoodRising.org
If you want to be alerted when I announce my freely downloadable 3D printable objects, just visit www.FoodRising.org and subscribe to the email list. I’ll be announcing the DIY videos and downloadable objects to the list all throughout 2015.
More announcements coming soon…