Making Spirit-Infused Beverages!

A bunch of members & friends of the Milwaukee Makerspace recently gathered to try our hand at something that does not mix well with all the heavy machinery at the shop: alcoholic beverages!  We attended a consumer cocktail academy hosted by Hendricks Gin at the Iron Horse Hotel, and we had a blast!

Check out our pictures:

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Chocolate Printer Cooling System Test

This week I attempted the first test of the chocolate printer cooling system.  The cooling system is intended to solidify the chocolate just after it leaves the extruder nozzle so that by the time the next layer is started it will have a solid layer to sit on.  The cooling system consists of a centrifugal blower with a brushless DC motor blowing room air into a styrofoam cooler containing a block of dry ice.  The air passes over the dry ice and gets chilled as the dry ice sublimates directly into very cold CO2 gas.  The chilled air and CO2 mixture exit the box through a port with a hose that will ultimately blow the cold air on the chocolate.  At least, that’s how it is supposed to work.  It blows air at -12C as measured via a thermocouple, but unfortunately, the air exit port ices up in about 2 minutes and blocks the air flow.

There are many possible solutions.  I can add a heater to the exit port to prevent formation of ice, or dry the air going into the box using a dessicant cannister or maybe just use water ice instead of dry ice if the higher temperature will still cool the chocolate adequately.   Maybe using an old miniature freezer with an air hose coiled inside would do the job.  It would be really interesting if I could use the waste heat from a freezer to keep the chocolate liquified and flowing.  Back to the drawing board!

Custom Police Badge

I was a “Grammar Police” officer for Halloween this year.  My costume consisted of some standard police equipment, as well as a dictionary, thesaurus, citation tablet, red pens, and, of course, my lovely custom badge!


Step 1: Design.

I scoured the web for pictures of “grammar police” shields, but ended up creating this design in Microsoft Word, using clip art from the web, generic shapes from Word, and shaped text boxes.  It was pretty simple and used the software I had readily available.  The portions of the design that are solid black are the parts that will be etched into relief during the process.


Step 2: Create!

With much encouragement & assistance from a fellow Makerspace member, Jon (of Dalek Asylum fame), I crafted this badge using mostly jewelry-making tools & methods.  We first spray-painted a square piece of copper, then used the laser printer to burn away the paint from the sections that were solid black.  This gave us access to the “fields” that would be eaten away in the etching process, giving the piece segments of relief.

After some clean-up (note to self: don’t use abrasive cleaners at this step next time!  and maybe not industrial spray paint, either), we left the copper square to soak in ferric chloride for approximately 45 minutes.  We checked the progress of the etching every 15-20 minutes, and decided that after 45 minutes we had enough of an etch to give the details enough depth to stand out.

After more clean-up to remove the ferric chloride & remaining paint, I had a nice, shiny, scratchy piece of copper with an etched design.  At this point, I really started finding my way around the jewelry bench.  I used a small jewelry saw to cut along the outer lines of the badge, which was frustrating until I found the right rhythm for cutting.  My badge was finally starting to take shape!

From here, I filed the edges smooth & buffed the finish to remove some of those fine scratches.  I gave the piece some dimension by using tools at the jewelry bench to accentuate the “belly” at the bottom of the shield.  Once it felt reasonably even and I was happy with the general appearance, we applied a liver of sulfur gel to the surface of the badge.

The liver of sulfur settled nicely into the etched corners, giving the piece an aged patina and highlighting the small details.  I really like how it settled into the fine lines left by the etching solution around the perimeter of the main field!  The small striations in the copper there give it a very unique appearance.  The patina provided by the liver of sulfur also helped hide some of those fine scratches I mentioned earlier.  We wiped off the excess & applied a museum-quality wax, since the badge will be worn and handled like jewelry, to maintain the patina.

Step 3: Profit(?)

The badge was added to my collection of Grammar Police equipment, which included shiny aviator sunglasses, and a tactical belt (excess nylon webbing with a clasp) with a dictionary, thesaurus, red pens, custom grammar citation padlet, and toy handcuffs.  It was quite the fun costume, and even though none of my trick-or-treat’ers understood, all my friends did!


Thus ends the story of my first Makerspace project.  Oh, what fun it was!

Chocolate Cooling System Almost Ready For Testing

Chocolate printer progress continues.  This week was devoted to the print cooling system.  The chocolate will come out the extruder nozzle in a semi-molten state.  It needs to solidify by the time the next layer of chocolate gets deposited on it, and I’d prefer it doesn’t drip or sag, so it needs to be chilled right after extrusion.  The current plan is to blow chilled air over the chocolate just after it leaves the extruder.   The chilled air will come from a foam insulated box containing a block of dry ice.  There will be a blower pushing air into the box and a hose delivering the chilled air/CO2 to the print.

A couple weeks ago I got a blower from American Science and Surplus and this week I got it running by using a model airplane ESC and servo tester to drive its brushless DC motor.  It appears to be capable of blowing much more air than I’ll need.  There are many unknowns yet to test.  How much chilled air/CO2 will it take to solidify the chocolate after it leaves the extruder?  How long will a block of dry ice last when used this way?  Will ice build-up inside the chiller box adversely affect its performance?

I designed and printed three parts for this system- a mount to attach the blower to a foam box up to 1.5″ thick, a hose coupler to allow delivery of the chilled air/CO2 to the print, and a hole saw to cut holes to fit the other two parts.   The printed parts fit as if they were designed for the job!

3D printed hole saw

3D printed hole saw

Hose connected to hose coupler

Hose connected to hose coupler

Hose coupler parts

Hose coupler parts

Blower mount for air chiller box

Blower mount for air chiller box