Sparks!  The VDG produces about 400 kV.

Then I found a plastic bucket and the fun really started.  We had kids and many adults who were definitely much too heavy, standing on the bucket and making their hair stand up with moms, dads, boyfriends, girlfriends, husbands, wives, partners all taking pictures.   I had to move one gentleman who was breathing oxygen from a tank away from the machine.  Fortunately, no one fell off the bucket or caught on fire, and next year we’ll do it right and take a block of styrofoam for people to fall off of  to stand on.

Kylee was ready to join the Makerspace just for this… and with that shirt, she’d fit right in!

Blondes really do have more fun!

Even Gordon couldn’t resist!

Last year Son of MegaMax (a 3D printer built at the Milwaukee Makerspace) went to the Faire.  This year he had two companions to keep him company- an extra-beefy printer being built by Erich Zeimantz: MiniMax XY.  MMXY isn’t complete yet, but promises to be a super high quality, high speed printer.  He’ll be operational at next year’s Maker Faire.  SoM also brought his big brother, Ultra MegaMax Dominator, named that because he is ultra, mega, maximum, and he dominates.

MiniMax XY at Milwaukee Maker Faire

Ultra MegaMax Dominator and Son of MegaMax at the Milwaukee Maker Faire

UMMD and SoM rotated between the booth and the dark room where the both printers’ UV lighting and fluorescent filament was a big hit.

UMMD in the Dark Room at Milwaukee Maker Faire 2017

We had a few things besides 3D printers at the booth.  Tony brought in some Bismuth crystals to give away, and surprisingly, they didn’t all disappear in the first hour.  Tony thinks people left them because the Makerspace logo on the info board on which the crystals were sitting looked a lot like the skull and crossbones that usually indicates poison.  The crystals do have an other-worldly toxic look about them.  Oh well…

Bismuth Crystal

Marcin’s LED signs on the table at the booth and hanging above the entrance to the Dark Room were also very popular and hard to miss, though I managed not to take any pictures of either.  The one above the Dark Room was so bright that if you saw it, you’ve probably still got its image burned into your retinas.

Everyone involved had a great time and we’ll be there again next year with even more cool stuff!

The request went out on the message board. Pete P., Shane T., and I all expressed interest, but life got in the way and it soon became a matter of whomever got to it first would be the one to make it. I ended up devoting the better part of last weekend to this project (much more time than I anticipated) but I can honestly say I’m pretty happy with the result.

The goal was fairly straight-forward: make an enclosure for the switch Tom had already provided. It was a color-coded, 4-button, mechanical switch that had been wired to provide four settings: OFF, LOW, MEDIUM, and HIGH. The more laser cutters in use, the more air you’d need and the higher the setting you should choose. There’s four duct connections available for the three laser cutters we currently have.

There’s a saying: “Better is the enemy of done.” Truer words have never been spoken in a makerspace.

At first I wanted to build the enclosure out of acrylic. Then I remembered this awesome plastic bending technique that Tony W. and some others told me about. I found a video on the Tested website and got inspired. (If you don’t know about Tested, please go check it out. You’ll thank me later.) Unfortunately, my bends kept breaking and melting through, so after a few hours of tinkering I moved on.

Thankfully, we have a small cache of plastic and metal project enclosures on our our Hack Rack. I managed to find a clear plastic, vandal-proof thermostat guard. It looked workable.

I tried laser cutting it, but the moment I saw the plastic yellow and smoke, I knew there was probably some nasty, toxic stuff in it, so I moved to the CNC router. About an hour later I had my holes cut.

Then came the wiring. Up until this point I had been focused on the control box itself. Now I wanted to add a light!

No, two lights! Yeah!

One light to tell you when everything was off, and another that lit whenever the fan was in use. People could look at the lights from outside the room and instantly know if the fan had been left on. (It should be noted that the new fan, despite being twice as powerful than our last, is actually much quieter. Tom added a homemade muffler to the inlet of the blower and shrouded the whole contraption in 3″ fiberglass batt insulation. The best way to know if the fan is running is to open a slide gate damper and hear air being sucked in.)

OK, I totally got this.

Draw myself a ladder diagram and get out the wire connectors… Remember that I need to isolate the signals from each other so any button doesn’t call for 100% fan… A few more relays… Some testing… and done!

Wait a second… the motor drive doesn’t have a ground for the control signal.

Hmm.

Guess I can’t power it from the drive. I’ll just tie into the drive’s ground. Nope, that didn’t work.

I’ll read the motor drive manual. OK, it has a set of “run status” contacts I can monitor.
….and they’re putting out a steady 0.4 volts DC. That’s enough to light up a single LED! …except, no. It’s not lighting. Doesn’t seem to be any real current.

I’ll just use a transistor! That’s the whole point of a transistor!
….well nothing I tried worked.

I’ll build a voltage multiplier circuit!
….and this isn’t working either.

On Day 3 of this “little project” Ron B. made a comment about using a pressure switch of some kind.

Wait.

We have a Hack Rack full of junk and I know there’s this old bunch of gas furnace parts. It couldn’t be that easy…

Yeah. So, three days (and a few frustrating epiphanies) later, this all came together. Press the beige button, get some air. Press the other buttons, get some more air. Any time there’s suction, the red light comes on. The indicator light is powered by its own 24 volt DC wall pack. The pressure switch has both normally open (N.O.) and normally closed (N.C.) contacts so it would be totally feasible to add another light at some point. The controller could display “OFF” or “SAFE” or whatever as well as “ON” or “FAN IN USE” or whatever. The text is just a red piece of paper with words printed on it, then holes laser-cut out to fit. We can trade it out with different words or graphics if we ever feel the need. I was just glad to have it done, so I called it. Better is the enemy of done, indeed.

You can learn more about the evolution of our laser cutter venting system on our wiki!

The laser cutter is now connected to the new vacuum pump!  I’d still like to do some endurance testing on it to fully put it through it’s paces, and we need to finish the last leg of the vent pipes up in the loft, but otherwise you can use it to cut wood and such just as you did before.  I wouldn’t suggest cutting any plastic just yet as the vent pipe is just discharging over the hallway by the bathrooms.  There’s an instruction sheet on how to turn the vacuum pump on and off taped to the machine and my contact number if you run into problems.

You can see pictures here:
http://www.flickr.com/groups/milwaukeemakerspace/pool/with/6471649899/

With 110 Volts at its input, the transformer put out 9000 Volts! The arc formed across the gap, but it wasn’t actually a high enough voltage to make the arc ascend the ladder. When I hooked the transformer through a Variac and turned the knob to 130 Volts, the arc began to ascend the ladder – but only a few inches. The obvious solution was to add more voltage, so I hooked another Variac in series with the first, turning this one to 140 Vac. With the output of the transformer a bit under 12000 Volts, the arc ascended over 2 feet up the ladder. Check out the video below showing the arc’s interaction with wood.