JimT

Thanks. It's good to know that the North America Support website has information on the UM2(non+) that also applies to the Go.

Thank you! My UM2Go has the spring too. Are the instructions for replacing the coupler on a UM2Go somewhere on the Ultimaker website? I couldn't find them. The UM2Go User Manual says that the instructions are on the website, but it doesn't have a link.

I've just replaced the PTFE coupler on my Ultimaker 2 Go. I wasn't able to find instructions on how to do this for the Go, so I used the instructions for the UM2+ on this page: https://ultimaker.com/en/resources/50672-replace-the-tfm-coupler The print head on the Go is similar, but not exactly the same as the UM2+. Step 6 for the UM2+ says To tighten the front two thumb screws, use the calibration spacer. Place the tool in between the aluminum plates of the hot end. Tighten the front two thumb screws until the tool fits securely between the plates, but can still easily be removed. I did not get a calibration spacer with my Go. Does the Go use the same calibration spacer as the UM2+? Where can I get one? Can I print one? Thanks!

If that's the case, then it is a bug in Cura, which should be fixed.

If you look at the footprint of the object, it does not come close to the clamps, so that's not the problem.

I posted this in the printer forum, but no one there responded. The Ultimaker 2 Go is advertised as having a build volume of 120 x 120 x 115 mm, but I am frequently unable to print objects smaller than that. I get a message from Cura 4.0.0 saying that it is unable to slice because the model doesn't fit in the Go's build volume. I have Support and Adhesion turned off, so they shouldn't affect the build volume. I've attached an example STL file that won't print on my Go, even though it is significantly smaller than the Go's advertised build volume. I've also attached a screen print showing the error message that Cura issues. Is the Go's build volume smaller than advertised? Or is there a bug in Cura? go_test.stl

The Ultimaker 2 Go is advertised as having a print volume of 120 x 120 x 115 mm, but I am frequently unable to print objects smaller than that. I get a message from Cura saying that it is unable to slice because the model doesn't fit in the print volume. I have Support and Adhesion turned off, so they shouldn't affect the print volume. I've attached an example file that won't print on my Go, even though it is significantly smaller than the Go's advertised print volume. Is the Go's print volume smaller than advertised? Or is there a bug in Cura? go_test.stl

For large pieces, you only cast a bronze shell, which is typically about 6mm thick. This usually means that you have to cut windows in the hollow wax to allow the investment to fill it, and use bronze pins to hold the interior investment in place when you burn out the wax. After you cast it, you weld the the windows back into the piece to make it appear solid, and then file and sand it smooth.

Centrifugal casting machines are the most common kind used by jewelers and they can give very good results. There is a wide price range. Here's a link to a relatively inexpensive spring-driven casting machine. It can handle flasks up to 4" x 6" (102 x 152mm), although the flask that is included with the machine is smaller (90 x 102mm). The wax or PLA model shouldn't be any closer than 12mm from the sides and bottom of the flask, and 25mm from the top, so that limits the size of the pieces you can cast. This machine doesn't include a shroud so you will need to buy or make one. It is unlikely to fail, but if it does, you don't want it to throw molten metal on you. Here's a link to a better (and more expensive) Neycraft Spincaster. There is a link to video on this page that shows how to use it. There are other machines that are much more expensive that have electric motors rather than springs, but they don't give significantly better results. I've seen casting into ceramic molds, but haven't done it myself. It's more expensive than plaster, but I don't think that it is a lot more expensive. It is a more time-consuming process than plaster, and is typically used for larger sculptures. Ceramic shells can't be used in a centrifugal caster, and they are rarely used by jewelers. Here is a link to an overview of the ceramic shell process. For best results, don't use ordinary plaster of Paris. Use a plaster that is formulated for investment. The biggest problem with plaster is air bubbles. There are vacuum systems that can remove the air bubbles from the plaster. I find that it helps to paint the plaster onto the model with a small paintbrush before embedding it in the plaster. This helps to avoid getting air bubbles on the surface of the model, which causes pimples on the surface of the metal. The issue with PLA is that it expands before it burns out. This can crack the plaster or ceramic investment and cause the cast to fail. To avoid this, you can paint a thin coat of shellac on the PLA before investing it. The shellac burns off quickly, leaving a little space for the PLA to expand.

It is possible. I cast this piece using a centrifugal casting machine because it is small, and it takes some force to get the metal to fill the mold completely. Larger pieces are easier. I've cast larger pieces in bronze without any special casting equipment. You will of course need some sort of kiln to burn out the wax or PLA and a way to melt the metal. I used plaster investment, and there are always some surface imperfections that you need to file and sand when you use plaster. Ceramic shell investment gives a better surface.

I've previously posted some of my jewelry designs that I made using a program that I'm writing in OpenSCAD and that I printed on my UM2GO. I've printed over 60 of them in PLA so far. This is the first one I've converted to metal. It was cast using the lost wax casting process, but using a 3D print instead of hand-carved wax. Although I have done several successful casts using PLA (like the bronze bust in my profile pic), I decided to use castable resin for this piece. This resin has several advantages over PLA for casting. I have access to a Form 2 printer and casting equipment at the local community college, and I used them to print and cast this piece. After casting this pendant in sterling silver, I used liver of sulfur to give it an antique-looking patina and increase the contrast. It is 45 mm long (about 1 7/8 inches), and contains more than an ounce of silver. The second photo shows the pendant with the original PLA prototype printed on my UM2GO. I like to print the prototypes bigger to make it easier to see the details in the design. I've made over 100 pieces of jewelry in the past 4 years, using a wide variety of materials and methods. This is my favorite so far. This is the first of a series that I think I'm going to call "Fossils of Planet Phaeton".

What kind of conductive paint do you use?

Beautiful!

Looks great!

And a couple of pics of the basic shape in the design at the upper right of the second photo. I made this one for February 14.

Here are a couple of pics of the basic shape used in the three bug-like designs in the first photo.

I'm so sorry about the power failure. Some other brands of 3D printer will automatically resume printing after a power failure. Perhaps Ultimaker could add that capability. I hope you can complete it. I'm looking forward to seeing it.

They certainly show self-similarity, but there is no recursion in the current version of my OpenSCAD module. Recursion is a specific kind of algorithm that I have not yet implemented in my code, although my code often gives similar looking results. The chapter on fractals in Daniel Shiffman's book, "The Nature of Code", has a good discussion on fractals and recursion. Here are a couple of sound bites from it. "While self-similarity is a key trait of fractals, it's important to realize that self-similarity alone does not make a fractal." "Another fundamental component of fractal geometry is recursion. Fractals all have a recursive definition." http://natureofcode.com/book/chapter-8-fractals/ My current code doesn't allow me to define a design with a recursive definition, so technically, my designs aren't fractals, although many of them do have self-similarity at different scales. I'm probably being a bit pedantic about this, but recursion is kind of a big deal to me. It would allow my code to generate designs of a much higher level of complexity than it can currently generate.

Thanks! The scarab-like ones are my favorites so far. I think of them as bugs from another planet. The filament is 3D Universe Green PLA. I bought a lot of 3D Universe filament during their Winter sale, and it is working well. I just started writing my OpenSCAD module in January. Although it is still quite simple, I'm happy with what the designs it can generate already. I have a lot of ideas for features that I'd like to add to it by the end of 2018. One of them is recursion. Recursion would enable it to generate true fractals.

It's the fractal look of your piece that attracts me to it. My OpenSCAD module is based on the concept of defining a shape, and then repeating it at different locations, sizes, and orientations. This can give fractal shapes, as well as simple geometric designs. I've just posted examples of both kinds in the topic "More Jewelry Designs". Your print is looking great!

I'm doing a design-a-day challenge in 2018. I might create several new jewelry designs some days, and none others, but the goal is to have 365 printed designs at the end of the year. I'm currently ahead of schedule. I just finished printing February 22. I previously posted some of my January designs. Here are eight of the February designs.

Looks very cool!

Thank you!

What's the advantage of changing the feeder motor? Does it improve the print quality?

Another four test prints.