This script has a *lot* of variables you can tweak.  I don’t even feel like I’ve put everything into this script that I want to, either.

an incomplete list of parameters you can adjust:

• knob radius
• knob height
• shaft hole radius
• shaft hole height
• set screw inclusion, radius, and location
• flatness of shaft hole
• rounding on top (thanks very much to http://iheartrobotics.com for the articles on edge rounding!)
• indentations
• directional indicators
• plus a lot more!

About

One of the most stressful things about making multiple copies of an electronics project is reliably locating interface controls that you like. Maybe you can locate them one time, but can you locate them a year from now? two years from now? And how much do they cost?

For example, I found some slide potentiometer knobs at Mouser.com for about $0.50 apiece two years ago, and they ran out of them… forever. I tried sourcing them elsewhere, and the best I could find was a seller that had them for $4.00 apiece (!!wtf!!). So that really sucks.

One strategy is to buy in bulk. But, buy too few and you may run out and pay twice for shipping.  Buy too many and you  end up with unused knobs sitting around not making your money back. That also sucks.

Round potentiometer knobs are somewhat readily available. But still, they can be from $0.80 to $5.00 each, and if you can’t find enough for your project, that can be problematic. Mostly I’m tired of paying multiple dollars for things that should basically cost $0.25 apiece. Aesthetics are important too, so having options beyond what’s out there is nice.

A different strategy is to print them yourself as you need them.  No shipping, no running out, and you get to call the shots on how it looks and how it fits. Now, I like this way. Plus, for my project, making the knobs just goes along with the rest of the stuff I’ve done myself.

Well... some are better than others. Limited success is better than no success at all.

Download

Click here to download the parametric potentiometer knob generator OpenSCAD script.

License

parametric potentiometer knob generator by steve cooley is licensed under a Creative Commons Attribution-NonCommercial-ShareAlike 3.0 Unported License.
Based on a work at sc-fa.com.
Permissions beyond the scope of this license may be available at http://sc-fa.com/blog/contact.

edit 2012-02-01 : my voltages were set to the makerbot motors, where the should have been set to the moons motor voltages. :-\

For my kids, I think 3d printing is going to be one of the important tools of their lives. It uses the stepping stone that I was given and takes it further. Now not only can you visualize anything your mind can think of, but you can hold a copy of it in your hand. No doubt that 3d printing at home is in its infancy, much the same way that computers at home were when I was a kid. So, to me, 3d printing appears to be the most likely tool my kids can have to propel them into their future. In my opinion, a 3d printer in the home will foster: problem solving skills, imagination, healthy non-conformity, the concept of iteration, no fear of being wrong or failing, and hands on application of the scientific method.

So, I’m in research mode. Here are the links I can find to commercially available sub-$5000 hobbyist 3d printers. I’m mostly focusing on fused deposition modeling type printers. The other technologies I’ve seen for 3d printing are either experimental, lacking in resolution, lacking in base affordability, or the media is too specialized (and presumably expensive).

MakerBot Industries has one called the thingomatic. These guys have been at the heart of the maker/DIY front and honestly, they have a lot of momentum. Their machines are iterating very quickly, and they have a huge community rallying around their project. Their laser-cut plywood product is undoubtedly borne from the DIY mentality their product aims to foster. They have some super nice features like an automated build platform, and a new dual extruder head option. They’ve generated a lot of buzz about attracting $10M in investor funding, so it’s likely they will be able to afford support staff for the foreseeable future. Has Mac software available and/or printing from an SD card. Their wiki and build instructions are incredibly detailed. $1,299 kit, $2,500 assembled.

Reprap, represents the wild west of 3d printers. It sort of kicked off the DIY 3d printer revolution happening now. As such, it’s really focused on bootstrapping quickly with the least amount of time spent on worrying about what the machine looks like. (what the machine looks like?? Look what it’s DOING!) There’s no official source for parts. That’s kind of the point, though. It’s open source, so you need to find someone who will print our the parts for you (and you presumably pay them)

botmill surprise! a presumably reputable source for reprap based 3d printer design. No exterior enclosure, all wires exposed. This machine will undoubtedly appeal to the mad scientist crowd. $1,395.00 assembled. Pretty cheap, actually.

Ultimaker The videos I’ve seen of this thing are of it printing really really fast. Designed and sold out of the Netherlands. €1,194.00 base (kit)

UP! best consumer based enclosure design. The machine itself looks great. Sensible and clean. Definitely made to alleviate concerns about reliability and reputability. Looks like a real product. Compact. Comes with integrated software. Higher on the price scale. Has Mac software. You’d think they could price it under $2650+~$150 shipping. C’mon, China. What the hell. Alibaba says I can buy whole laser engravers for that price.

RapMan. Pretty. laser cut clear acrylic. Alibre sells software, so they probably will support the machines they sell for a while. With the revolution happening at the pace it is, your mileage may vary on how long they do support it. (5 years?)

Bits from Bytes 3DTouch lots of options for number of print heads. mo’ printheads, mo’ problems. It may be the most capable from an aspect of possibilities, but the workflow must be significant to munge multicolor GCode. Maybe not.. It’s probably right on the edge of being past the scope of being a machine for the home.

buildyourcnc’s white ant I have the buildyourcnc.com blacktoe 2×4 cnc machine and it’s great. Their white ant 3d printer is still in active development, and given the flexible nature of their design ethos, this could be cool. The downside here is that you can’t buy everything you need right from them. You have to pick up some of the required parts from MakerBot. Which is kind of a drag. What I think we owners of blacktoe and blue chick machines are waiting for is some word about why an extruder print head for our existing machines is impossible. I guess I could image why. I’d gladly replace my 3 axis control board with a 4 or 5 axis board if I could interchangeably use a router or a 3d printhead. GLADLY. Use the motion control table and hardware I already have for multiple tool heads? Yes, remind me why I can’t have this? A ridiculously large 2′ x 4′ FDM 3d printer. It’s probably impossible because its a ridiculous idea.

So, for me, time to make a verdict… and that task is pretty easy. MakerBot has the juice right now. I love how they’re dedicated to the movement and driving innovation. They have lots of instructions and a huge community. And funding, so more brains getting paid to focus on it means good things for the future.

If price is a sensitivity for you, buildyourcnc’s white ant would be a good choice, with botmill coming in a close second. If I was in the Netherlands, I’d probably go for the Ultimaker. UP! sure looks nice, but I can’t fathom why it’s so expensive. Cut the price in half and then it’s a horse race.

http://bengrosser.com/projects/interactive-robotic-painting-machine/

Interactive Robotic Painting Machine (2011) from benjamin grosser on Vimeo.

I’ll be honest, I’m doing things in quartz composer and processing that I wish I could do on the canvas. So maybe I should follow Ben’s lead. The unspoken lessons here are: 1. set your expectations low on the resolution of the resulting product, especially if you want to cover the canvas without it taking all day. 2. Don’t worry about cleaning the brush. 3. Do worry about the fluid viscosity of the media. 4. love the result for what it is now. Let the historians decide if it’s good or not. The process is awesome, and that’s worth a lot to me.

sCCweet (cheesily said: “shweet”) for the Korg iMS-20 is a MaxMSP compiled application for mac os x that connects to your iMS-20 app through your existing MIDI connection (figure that out ahead of time). It randomizes the parameters of the iMS-20 at an adjustable rate so you can explore different combinations of settings that you might otherwise never run into on your own. It’s pretty random. There aren’t a lot of controls. Think of it as a spelunking tool for this synth. Enjoy!

Download “sCCweet for the Korg iMS-20″

so, do yourself a favor so you can follow along. Open this page up in a new tab:
http://wiki.moderndevice.com/pmwiki.php?n=MD.ListVoices

then hit the play button below to listen to 64 notes of the first bank of 128 different voices of the fluxamasynth shield. I just realized that I hit the record button while I was uploading a new firmware… so when you hear the “piano” start playing… that’s when you start reading down the list of voices on the other web page:
fluxamasynth_audio_samples_bank0.mp3

I just picked up ArtRage for the iPad, and it’s pretty awesome. I’ve already been on a major cat-drawing kick lately, so when this new natural-media style drawing/painting app became available, I dove right in with this:

Brushes app is another great tool for drawing/painting on the iPad. Here’s an example, although you’ll find another piece I did further down in my posts of some orchids that also show off what brushes app can do.

So far, there are some really great apps out there for the iPad that have one or two great features that make them useful. I think there’s still a perfect storm of features that I want to see.

1. Natural media synthesis/mimicking — artrage
2. record all brush strokes and actions for playback for either movie or high res render on a desktop machine – brushes.app
3. remote palette with ipad, iphone, or desktop.. one of them anyway. I have all three, let me use one of them that I’m not drawing with to be the utility space so I can focus on drawing on the drawing space. Remote Palette

These apps are fun to use, and I’m going to keep using them. The reality is that these are great apps to use for illustrations and for fine art if you’re going to display them online. Prints from digital art just don’t have the marketability like actual paintings, so the destination for these pieces has to be different. When you see covers of magazines being done with these types of apps, yes, that’s exactly where you can make some money being an expert at using iPad painting apps. Doing live portraiture using an iPad, yes. Using the iPad with a painting app to do a plein air sketch to use as reference back in your studio… perfect. The utility of using the iPad for fine art is there. No question in my mind. It’s just not a straight A to B type of path. Chances are good that you’re just not going to make a living as a fine artist using digital tools exclusively… so you need to figure out where the career path is using digital tools, AND/or keep using traditional media. “AND”… as in… do both. These digital tools are really cool. And so is having an actual painting that you painted without a computer. Do both.