Tips on Getting Started, Part 1 - Cura

Getting Started with Cura

My coworker from the first post suggested that I print existing models to learn what to expect.

I printed 8 cookie cutters from Thingiverse, then started printing the Pip-Boy pieces (also mentioned in the first post). Later on, I downloaded things like Open Forge terrain for D&D, D&D figures from Shapeways, and watch stands from Thingiverse.

After the first couple of items printed, I probably could have moved onto the "difficult" pieces. But as a caution: just because it was modeled in 3D, doesn't mean it will print well.

Profiles in Cura

Cura has a "basic" setting that didn't work for my first print - I ended up jumping straight into "Expert mode". Expert mode uses Profiles to manage general settings for what material you are using, and how fine you want the details. This is primarily addressing extruder temperature (melting the plastic), the bed temperature (so there's a consistent temperature once the plastic has been "printed" - allowing for regular adhesion)...and then Layer Height for detail (the smaller the number, the finer the detail). A distant fourth quality is "in-fill" - if you have 100% in-fill, it will be a solid object. More plastic, longer printing, heavier...20% is considered "enough", but if you want additional heft or strength...

If you need to use gcode to print, these profiles will be included in the gcode instructions.

Standard profiles can be found on the lulzbot website, and probably anywhere you downloaded Cura from. (I did fast printing for a long time. It's rare that I use "fine" printing.)

Adding Useful Information

You bought some PLA/HIPS? Great. In File>Preferences>, you can put the Cost/kg. This will give you an idea on the cost of your model - it's probably cheaper than you think. My current standard price is about $25-30 / kg.

Rules for 3D printing

It's ridiculous to have rules for this, right?

1. The object needs to be small enough to fit on the printer bed. (I think the Lulzbot Mini has a 6" x 6" x 6" area.) One of my early-modelling projects was designing a 9" diameter braiding wheel. I cut it apart in quarters in Blender, then printed the 4 pieces in Cura.
2. The printer can only reasonably handle 45 degree angles as it builds vertical layers. Beyond that, the plastic has nothing to layer on top of. If your object has overhang issues, Cura's answer is "Support: Everything". It will leave some rough parts where you remove the support, but it doesn't use a lot of plastic - and doesn't cause your model to collapse as it would without the supports. (I've aborted a half-dozen printings because of not having support turned on.) Cura is an all-or-nothing choice, when it comes to supports.

Slightly Advanced Choices

Rotating the Model

Sometimes I'll change the model's orientation to the printer bed. Usually so there's less support needed, or so that the smooth surface from the bed. Cura's generous with rotating (and bringing in models) - it will always bring the object up into the printing area. This is nice if you don't create your objects above the origin point in Blender.

Scaling the Model

Ugh. I think my biggest issue with Blender is scaling, due to its use of "Blender Units" or BU. They actually export as millimeters. I'll talk more about the measurements once I talk about Blender in-depth. Fortunately, Cura is good about scaling your models. My initial braiding wheel was usually boosted by 28:1 scale in each axis.

Printing Multiple Objects

When I'm printing multiple small objects, it's convenient to load them all onto the platform in Cura. This reduces the start-up time for the printer - the Lulzbot Mini needs to scrub off the plastic on the extruder from last printing session, and auto-level the bed again. This tacks on 3-5 minutes, which becomes a more onerous task if you're printing things one after another. Under Tools, you can choose to print all at once or one at a time - I recommend one at a time, so that the temperature is consistent for adhesion.

The Software Tools

Overview of the Software Tools Used

The best part of these tools: they work regardless of OS - Windows, Mac, or Linux. There's a couple pieces of software I installed on my 2008 Mac Pro (this is nearly 8 years old). It has 16 GB of RAM and is running 10.9.5 Mavericks. I have a Linux laptop with 8GB that can handle Blender.

Cura

The first piece of software came with the Lulzbot Mini - Cura. Cura is an open source "slicer". Basically you need a slicer to create instructions to send to your printer. You can put multiple objects on the virtual bed, scale/rotate them, and add supports (we'll cover this later). The instructions are exported in "gcode" - mostly important if you are putting those instructions on a memory stick and putting the stick into your printer. (This is not an option for the Lulzbot - it needs a computer hooked up to it.)

If you are just downloading models from the internet - that's ALL you need.

Blender

The second piece of software I installed was a 3D modeling program, to create new objects. I settled on learning Blender - none of the software I found was strictly meant for 3D printing. Blender is also open source/free. It has a lot of features, including animation and video editing that I won't be needing. I considered Google's Sketch-up - it's supposed to be much simpler and easier to grasp. (As it wasn't meant for 3D printing, it can sometimes require MeshMixer to make it a solid object to print.) In the end, I was going for a complete learning experience, and wanted more tools than I needed. If you're a student, you might check out Maya - a friend mentioned he got a 3-year license for free/cheap. Tinkercad and Fusion 360 are often used by other 3D printing people.

The file type Blender saves is ".blend", but you can export it as an .stl file, which is what ...most? slicing software use. If I have made progress on an object, I will usually try to save it every 15 minutes. My naming convention is similar to what I practiced when learning ruby - 5.2.1. This would mean I've gone through 5 major revisions, I am on the second minor version (but pretty much version 5), and the first minor tweak to the minor version. I have a simple text file, where I take quick notes on what the new version added in case I come back to a project 6 months later.

If you are looking for a simple design+print solution, you can stop here.

Octoprint

Octoprint takes over the "print server" aspect. My Lulzbot needs a computer to push the gcode to it, but it doesn't care too much about what computer does it. I picked up a Raspberry Pi B, a wireless USB stick, and a 8+GB micro-SD card. I would probably wait a month or so before adding it to your process - I'll eventually have a documentation of how I set mine up. The cool part of Octoprint is that  if you attached a cheap USB camera (goodwill=win!), you can watch what it's printing or even get a time-lapse done. Another benefit of Octoprint is that you can have multiple computers feed their models to it - laptop, desktop...it doesn't care.

The Start is not the End

The Disclaimer

Disclaimer: I am not an artist, electrical engineer, or a professional programmer.

I thought at least SOME of these would ruin the experience. I was horribly wrong. And not the "you need them all". You need none of these skills. Maybe someday I'll develop extra skills along those lines.

The Beginning of the Maker

I like the idea of making things. I have a dozen or so "MAKE" magazines. My dad had a woodworking shop in the basement where I grew up. One of the things that religion focuses on is the Maker or Creator - it's a high calling.

You want to feel good about yourself? Create something. Do art, cook, weld, drill, glue, sculpt, music. (Gratitude isn't a bad method to feel good, this is about making.) I cook. I like some game design...but I'm not really an artist. I like architecture, but not freehand.

The 3D Print Maker

At one point, I start saving towards a printer. I wanted a list of a dozen or so things I wanted to make, before I started shopping. Was this a fad for me? How serious was I going to be about printing? It took about a month in my off-time. Custom cat-toy feeders (too easy? Print a new one with smaller holes)...game pieces, a specialized pill dispenser (controlled by Arduino, Raspberry pi?), a braider's disk for the girlfriend, dinosaur cookie cutters, flora for D&D games, a shotgun loader for a Nerf gun, a tootsie roll stamp (look up Toot-Sweet Factory from a long time ago). The final game breaker was a PipBoy for Fallout 4. Found here: http://ytec3d.com/pip-boy-3000-mark-iv/

Researching the Printer

I will start by saying it's painful. I joined meetup groups (no responses), I browsed local Reddits. None of my friends were into it. None of my family had done it. An uncle of my girlfriend had tried a kit years ago, and had replaced his stepper motor several times - he has the part, but didn't bother, and I don't know if he ever actually printed.

Eventually through networking at work, a coworker mentioned a guy down on 6th who had done some printing. I tracked him down for lunch.

His experiences:

• Also a kit: he has an electrical engineer background
• Yes, a heated bed is awesome - he installed one later on
• "Auto-level" on a bed is needed - it gives your printer knowledge on the slope of the bed, if any
• Printers are not really that noisy (reviews all had checkmarks on noisy), not more than a paper printer
• Only ABS is toxic-fume smelling. PLA smells like waffles
• PLA itself is natural except for dyes...you can get "natural PLA" without dye - kind of food safe
• Moisture is indeed bad. Invest in a cooler with a way to suck up moisture. (Or only print with one reel at a time, and don't let it sit for 6 months)

My Lulzbot Mini Purchase

I went with a Lulzbot Mini, for about $1300 on Amazon. Tom's Hardware gave it a  strong review as a plug-and-play printer. I wanted to spend time printing (and designing 3D models), not repairing the printer - troubleshooting what was wrong today. A different Tom did a great youtube walkthrough of the setup here. The 6" heated bed is nice, the auto-leveling bed is great.

I picked mine up in October 2015, and it's been a great experience.

Ordering Plastic

I ordered a kilogram of PLA from Amazon at the same time - this is a lot of plastic. If you are printing for a couple of hours every night for a month, this is about a month or two of material. (If you want to print with HIPS, Amazon was my source for this as my local stores don't carry it.)

I also found a selection at Fry's Electronics - I even found some on clearance, so I picked up some more. There's a local electronics shop also on the Eastside of Seattle called "Vetco". Really great people, knowledgeable and interested in projects. They had a lighter selection of plastic, but they carried the parts for the Octoprint.