Happy Esperanto Day 2016!

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Happy Esperanto Day!

In honor of Esperanto Day, aka. Esperanto Literature Day, aka. Zamenhof Day…

I hereby invite you all to learn about or to speak the international language Esperanto. Here you can buy the book The Hobbit (in Esperanto)!

And as a bonus (bonefiko) here is a link to your very own model of Zamenhof that you can 3D Print!

And… you can easily learn Esperanto via the Free online DuoLingo course!!

duolingo

https://www.duolingo.com/course/eo/en/Learn-Esperanto-Online

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Fixing Mesh Issues & Layer Gaps in 3D Printing

So today i had an interesting experience. As i have been lately, i sometimes go to the library to print out parts I’ve designed for my custom 3D printer project. While they print i use the time to crunch out upcoming essays for for school.

But this time instead of the printer happily moving along and producing perfect parts i got a rude awakening. The parts that came out looked like picture #3. Instead of my corner pieces being printed with two triangular pyramids and four “arms” they printed with one triangle, a “tail” and two “spaghetti blobs” on the side in a mess. It looked more like a deformed geometric fish instead.

Looking for info online i found helpful information on the Ultimaker Forum. It seems if i go into Layer view beforehand i can see what it will print out like and see any obvious gaps before hand. X-ray mode is even more helpful in a situation like this because if there are any faces or walls that have problems they get highlighted in bright red.

As you can see on mine, the bad models have several red triangular “internal” walls. The models have internal walls because they were created in Solidworks as assemblies from smaller parts and “digitally glued together”. Normally that shouldn’t cause a problem, but for some reason it did.

Currently i’m using Solidworks 2007 to create my 3D models. I wish i could use a good Open Source CAD program that works in Ubuntu Linux, but sadly none really exist. Not to my liking anyway. FreeCad has potential, but has a long way to go. OpenSCAD looks decent, but is for people who have mathematical minds. Sadly i don’t. And Blender has amazing graphics, but is not a CAD program. If someone could combine the beautiful elegance of Blender while stripping out it’s over-complexity and merging it with FreeCAD, and taking the user friendliness of Solidworks it would be perfect. Oh, and it has to be cross-platform (meaning runs on Ubuntu Linux). So until that day i’m forced to use a proprietary CAD program on a otherwise useless proprietary operating system, either on it’s own machine (or run in a virtual machine like Virtualbox). Far from an elegant solution. -End Of Rant. lol.

For me my problem was some sort of issue with the internal walls. Normally this should not be a problem. Since my version of Solidworks does not export whole assemblies as STL files (instead each separate part is exported into STL), I’ve been using 3dContentCentral to convert my CAD files into single STL files. Apparently the issue i ran into arises when i export my assemblies into single part files before converting them to STL. If i instead upload the entire assembly (and dependencies) and convert those to STL files it seems to work fine. Somehow that makes a difference when fixing whatever was wrong with those internal walls/faces. Whatever. At least i’m happy to find a solution.

I wanted to fix my bad CAD models from the beginning, but for example if i had a bad STL file that was not created by me and i still needed to print it, i could turn to Cura’s expert settings. In Cura’s expert settings there are some tools that attempt to “fix horrible” models that would otherwise fail to print correctly. I could have gone that route to print them anyway, but for me the better solution was to fix the source of the problem which was a bad CAD model.

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So, all in all, check your parts before you print them. Cura’s x-ray mode and layer mode are invaluable tools that can help you avoid problems with your 3D printing endeavors.

This site also gives some good tips on bad edge geometry and bad STL meshes.

Project Updates November 2015

80/20 1020 Extruded aluminum t-slot y-axis 3d printer bracket
80/20 1020 Extruded aluminum t-slot y-axis 3d printer bracket

The first update is that i’m still steadily designing new parts in solidworks for my custom 3D printer. This photo is one of two y-brackets that will hold the 1020 size t-slot extruded aluminum (from 80/20) y-axis beam. It looked good in Solidworks, now it just needs to be fabricated (3d printed) into a real-world working part (as with many other parts).

Y-bracket for custom 3D printer
Y-axis bracket for custom 3D printer

It’s really fun designing parts and then seeing them become real functional parts. Recently I’ve even been looking into a local program for CNC machinist training as a job. Apparently there is a large shortage of qualified CNC machinists in my area along with a booming and returning engineering and manufacturing hub here in the area.

While i was designing new parts and fitting them together i found a few minor problems with a few of my old designs being off and not lining up properly with the 1020 extruded aluminum. So i spent some time fixing that and cleaning them up a bit. Good to find those errors on the computer first than after i make the parts.

I received the prototype PCB’s for the XYZZY Motor Controller 1.0, The downside is I’ve found numerous errors that i missed, so I’ve been trying to fix those. But then to compound those problems the main circuit itself has a problem where the HIP4081A h-bridge chip circuit is only driving a motor (in this case a test load LED) in one direction. At first it was shorting out the other direction, but now i think it just loads the current down and does not activate one side of the hbridge. It’s actually driving me crazy trying to fix it and find the cause of the problem, but it’s still quite a mystery. Perhaps electronics is just not my thing. Perhaps i really should give up on that project after never being able to have good success. But i don’t know.

In plant breeding news: i was able to harvest three corn cobs this year. Two were decent sized purple husked corn cobs, the other was a good multi-colored flint. The third one had lots of kernel color diversity, it even had several speckled kernels, and chin-marked ones, and even some that had both speckles and stripes! I recently found purple sweet potatoes at Whole Foods and i will be trying to sprout one and grow my own slips for next year.

I was also able to grow a few good squash this year, some good progress on the pea breeding, and an excellent year with Joseph’s Watermelon Landrace. Sorry, i didn’t get good photo’s of the watermelons, but i had some excellent red sweet watermelons and some good yellows as well. Especially for Northern Colorado, the watermelons are the plant breeding project i’m most excited about and ironically having the best success. Can’t wait for next year! And all this despite it being an incredible difficult and strange gardening year!

Rediscovering 3d CAD because of 3D Printers

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This past week (maybe 2) I’ve been utterly obsessed with 3D printer stuff. It has gotten me excited about 3D drafting and CAD all over again. Simply because you can create a 3 dimensional object on a computer in a matter of minutes or hours and render it to look completely realistic, but now because of 3d printers you can actually make those objects (if you so wished)! Awesome!

Yesterday and Today I’ve been playing around with Solidworks again. My ancient 2007 version of solidworks. lol. But it works non-the-less. Although i’d love to try out Autodesk 123d Design (which is free). But, why oh why are there still no good CAD programs that run nativity on Linux. Especially if you have a Mac version. If it runs on Mac it can easily be ported to Linux. Why do you think the Arduinos and the rep-raps, and open-source, and so many other great things have taken over the world by storm? Yes it’s because they are great products, but also because they are cross-platform! Okay, End-Of-Rant.

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But Seriously, i actually really like designing something in CAD if it’s something i’m excited about. Today i ventured into the realm of something relatively simple, test tube racks. But sadly there are not currently very good designs for test tube racks available. Which actually surprised me. The three best places I look for pre-made CAD files are at 3dContentCentral, which is the oldest site of this kind that i ever encountered. It is mostly for people who use solidworks, but the great thing about the site is that it has a tool that can convert to and from many different CAD formats, including solidworks formats, IGES, STEP, STL, etc. The second is GrabCad. GrabCad is a new community also aimed at engineers sharing CAD models freely. It dosen’t have the nice file converter that 3dContentCentral has, but it has a vibrant community that provides feedback, help, and will check out your designs. Someone on GrabCad actually helped render the nice  looking wood rendering of my 1950s style test tube rack. How nice! Thank You! And the third is the famous MakerBot Thingiverse. Thingiverse is less focused on CAD formats and instead is focused on creative designs optimized for 3D printing. At minimum an STL file will be available for anyone to download and print on any 3d printer they have access to. I currently dont own my own 3d printer, but am currently using the Lulzbot mini that currently resides at my local library. How’s that for public access?!!

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So these are the three test tube racks i modeled today in Solidworks. Not super amazing i suppose, but i’m proud of them. My favorite is the nice wooden 1950s style test tube rack. I partly chose to start with that one because i have one that looks just like that looks like it was made by a monkey in china. It seriously is not as nice as my virtual one and not anywhere near as fancy looking either. But also because it is the standard test tube rack featured in the banned 1960s DIY chemistry book: The Golden Book of Chemistry Experiments. It was just begging to be brought into the modern world.

I then ventured into modeling a simple test tube rack because there were none available that i liked. I may make a smaller version of this one for 3d printers that have small print beds. Perhaps one with only 4 test tubes.

The last one i modeled after a nice round plastic test tube rack I’ve seen on the internet. I don’t have one, but I’ve been meaning to buy one. But i wanted to model one in Solidworks and create one that fit on a Lulzbot mini 6″ X 6″ print area that other people could print out too. So i made one of appropriate size and then made it able to split in two to be printed easily. I really like how the design came out. I hope to be able to test it out by printing my own sometime.

1950s Style Test Tube Rack:

Thingiverse3dContentCentralGrabCAD

Economy Style Test Tube Rack:

Thingiverse3dContentCentralGrabCAD

Round Mini Test Tube Rack:

Thingiverse3dContentCentralGrabCAD