Categories
Uncategorized

Development with Resistance

As you may know, I sell a variety of USB controllers (on Etsy and my own shop) and I accept custom orders where I work with the customer to build (and program) what they want or need. So last year someone got in touch with me and said “Your Dual Button looks great! I need it with a 2.5mm stereo jack though, and it’s going to control some [REDACTED] equipment.”

So this was not a USB controller, but they liked the form factor of my product. Well, no problem. I do custom. I got as much detail as I could about the device they had (which was not working anymore) and asked for photos. There was a resistor wired into one of the buttons, so I asked the customer to check it with a meter to get the value. He couldn’t quite figure it out, but we made some guesses based on the color bands in the photo and I came up with a solution.

With the 2.5mm stereo jack we determined which of the TSR (Tip, Ring, Sleeve) parts were ground, and each of the buttons, and which button had the resistor on it. One button supplied full voltage and the other a lower voltage. I didn’t find out too much about the extremely expensive equipment it was connecting to, but I didn’t need to.

I came up with an easy way for the customer to swap the resistor, and even sent spares of various values in case we didn’t guess correctly. I think it worked fine with our “guess” resistor, so maybe the equipment just looks for full voltage versus a lower voltage. Who knows? I don’t work in the [REDACTED] field.

I often find these projects fun and a little challenging. I probably don’t always cover the time I put into them, but often they’re a good learning opportunity and sometimes turn into a product or repeat business.

Categories
Uncategorized

Little Articulating Arms

little-hands-01

I’ve been prototyping a little helping hands thing using some 3D printed parts and miscellaneous hardware, mostly #8-32 nuts and bolts, and a few springs.

little-arm-model

The 3D part is pretty simple, a cube with two holes. It’s based on my Camera Accessory Mounting System (CAMS).

little-hands-00

First version… still figuring out how to connect everything…

little-hands-02

Springs for tension were added, but I might try using small wingnuts to adjust tension as well…

little-hands-03

Tiny zip ties hold the alligator clips in place. They can still rotate freely and are somewhat tight…

little-hands-04

Hard to see in this one, but I stacked two blocks on top of each other to allow rotation in both directions. I’ll keep working on this to see where it goes.

Categories
Uncategorized

Press Knobs

press-knob-model

You may remember that I recently printed a press. While the press works quite well, the one thing I didn’t like about it was the fact that I needed a screwdriver to adjust the tension. That was a quick fix though. You see, I am not a newbie when it comes to knobs.

I had one other issue when assembling my press. While it calls for M5 bolts, I only had M3 and M6 on hand, so I did what any Imperialist would do, and used non-Metric hardware. A #6-32 bolt is smaller than a 5mm bolt, but it’ll do.

You can see above the quick model I made in OpenSCAD. The idea was to built a knob in two parts around the head of the bolt. A nut tight against it would keep it from spinning loose. (We just need to finger tighten it anyway, not torque it down hard.)

press-knob-01

Here is out bolt, nut, and two printed parts ready for assembly.

press-knob-02

We put the bolt through the hole in the bottom. It needs to be screwed in as it’s meant to fit tight to give it a little more “bite” into the plastic.

press-knob-03

There! Screwed in all the way. (Not pictured: the power screwdriver I used to drive it in all the way.)

press-knob-04

Now we put the nut on. You can spin this all the way to the end so it’s up against the plastic.

press-knob-05

Once the nut is at the end I hold it with some pliers and gently tighten the screw by hand. (Not pictured: screwdriver I used to tighten the bolt.)

press-knob-06

Now we snap the top part in place and that’s about it. I was pleased that both the Prusa i3 MK3 at work and my Monoprice Maker Select at home did a great job of printing these parts and they fit together perfectly.

press-knob-07

That’s it! Tiny knob is assembled. That was pretty easy, and it works quite well. I am pleased.

press-knob-08

In my mind, the beauty of a 3D printer (like any tool) is that it can help you solve problems. This may not be world changing, but the fact that I can solve a problem by making a computer drawing of an object and then telling a machine to “print out” that object is still some sort of magic. But as the saying goes “Any sufficiently advanced technology is indistinguishable from magic.” So, yeah…

Categories
Uncategorized

Bolts and Such…

3D Part

I love it when a plan comes together! I also love it when you design things and then create them and they work. I like when you can design things to work with the hardware you have, or design things for specific hardware, and then order that hardware and it fits perfectly because you planned for it, and designed for it.

Spinny!

So often when building (without planning and designing) you end up grabbing whatever hardware is around and use it, and you might also grab whatever sheet material is around and use it, and you hope that the length of the hardware and the depth of the material work together, or maybe you make some deep countersink holes or make other weird decisions… When I can 3D print a part I get to choose the depth of the material, the size of the holes, etc. It’s wonderful.

Bolts!

But yeah, I really like when I can plan ahead of time for the hardware I need and then get that hardware. Also, I think I love Bolt Depot now. Prices seem good, shipping seems reasonable, and their web site is easy to use. And they package your hardware in little bags that are properly labeled and nice and clean. It’s sort of beautiful.

Spinnerator!

Oh yeah, I’ve also made good progress on my spinny button pressing thingy. And thanks to Bolt Depot I now know that I had some #8-36 bolts mixed in with my #8-32 bolts. And what!? I didn’t even know I had #8-36 bolts! Weird… Anyway, I look forward to a great hardware future.

Categories
Uncategorized

Beam me up!

Beam me up!

Beam systems make construction of thing easy, or precise, or both. I keep seeing more of these systems, so I figured I’d write-up the ones I’ve seen.

MakerBeam
Back in 2009 MakerBeam, a Mini-T open-source building system, showed up (on Kickstarter) and while makerbeam.com is empty, makerbeam.eu has lots of good stuff. You can also get them from our pals at SparkFun. There’s some bits and pieces on Thingiverse as well. (And, MakerBeam is open source hardware.)

MakerSlide
Bart from buildlog.net launched MakerSlide, which is an “Open Source Linear Bearing System” geared towards DIY CNC machines like laser cutters, CNC routers, and (now) 3D printers. MakerSlide launched as a Kickstarter project, and did quite well. It seemed to be continually out-of-stock, but Inventibles is now kicking in to fill the gap. There’s a whole system of parts that go with MakerSlide, and from what I can tell it’s a pretty solid system.

OpenBeam
There’s a new one, called OpenBeam, which is running on Kickstarter as of my writing this. It’s an open source miniature construction system. (See a trend here?) OpenBeam seems to cite that the fasteners and connecting plates used by other systems are what causes things to get costly. Their solution is to use standard sizes and common hardware to make the whole system easier and cheaper to work with. There doesn’t seem to be a web site yet, but you can check out the developers blog.

Bitbeam
A bit different is how I’d describe Bitbeam. Instead of extruded aluminum like the other systems, it’s typically made of wood, and describe as just “holes in poles.” :) In fact, Bitbeam is based on another system, Grid Beam. And hey, both are open source! Bitbeam is Lego Technic compatible, and you can make your own with a (powerful) laser cutter. Bitbeam is also on Thingiverse. Sweet!

Grid Beam
As previously mentioned, Grid Beam is sort of the older big-brother of Bitbeam. While Bitbeam is for smaller things, Grid Beam is for larger things. You can actually build things like vehicles and furniture with Grid Beams. It also appears to be the oldest of these beam systems, dating back to 2008. Check out more at gridbeamnation.com

Are there any other beam building systems I’ve missed?