GlassTItlecard

Explorations of Processes for Digitally Created Glass Castings

I spent much of 2015 taking a year long flexible fellowship at Wheaton Arts’ Creative Glass Center of America developing ways to cast glass from computer generated sculptural forms and wanted to take some time to share these learnings. I worked extensively with glass many years ago but now create most of my art with 3D scanning and printing. The Wheaton Arts’ fellowship was a unique opportunity to bring these two practices back together.

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Wheaton Arts is home to the Creative Glass Center of America in Millville, NJ, where I had a fellowship this past year to conduct experiments and create a workflow for casting glass from computer designed objects.

My work in the last few years has used a combination of 3D modeling techniques. I usually begin with 3D scanning,  primarily structured light scanning with Primesense/Kinect style devices and occasionally photogrammetry for non human subjects. Other non-organic forms are just modeled directly in the computer using my software of choice Zbrush. Next I will digitally manipulate and sculpt the 3D scans in the computer. Finally the work is output as a 3D print. My investigations this year took these techniques further, so that these digital sculpts were then realized as cast glass forms. I tried a few variations of lost PLA casting, as well as CNC milling graphite to make reusable molds. Enjoy.

Lost PLA Kiln Casting

The first technique I chose to explore is what people are calling “Lost PLA”, basically an evolution of the traditional lost wax kiln casting technique. Starting with a 3D printed positive of the form I want to cast in glass, I created a plaster/silica mold around my 3D print.

The actual recipe for the mold by weight was:

  • 16  parts water
  • 6 parts Hydroperm
  • 6 parts Plaster
  • 6 parts Silica (or olivine sand)
  • 1  cup 3/4″ fiberglass strand

This could be done with just a 50/50% plaster-silica mix, but as I understand it the Hydroperm foams and creates air pockets in the molds to make them lighter. The fiberglass strand helps strengthen the mold and helps wick out the moisture so the molds dry more efficiently.

I began by plugging any holes in the surface of the 3D prints with microcrystalline wax and waxing the prints down to a table. I then just cut strips of tar paper and hot glued them down to form a wall around the print, leaving room for about 3″ of mold thickness. I mixed a small initial coat of mix with no fiberglass strand to use as a splash coat over the object, then mixed subsequent buckets of mix to fill the molds completely. After the mold was filled, I let it set before tipping the molds on their sides to dry (having fans helped this).

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3D Print affixed to the table with wax and surrounded by a cylinder of tar paper

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3D prints and tar paper prepped for casting molds

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Splash coat on the 3D print

 

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Mold ingredients being dry mixed before the water is added

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Completed molds drying

After a minimum of one day drying (and preferably more like a week), the molds were ready to be loaded into the ovens. The PLA was still on the inside and needed to be melted out. With lost wax casting, the general practice is to steam the wax out of a mold. I tried this with the 3D printed PLA and barely got it to move at all. Steaming out PLA is not an option so it has to be burned out in an oven.

Even though PLA is a biodegradable corn starch, the burnout is smoky and not good to be around so it had to be timed to happen overnight when the studio was empty. I would begin by soaking the oven at 300˚ for about three hours and then pushing it upwards at about 100˚/hour. At about 450˚ I would go in (wearing gloves, glasses and a respirator) and use pliers to pull out some big chunks of plastic as it started melting. I had to be careful not to damage the mold in doing so. At about 700˚, I would go in with a stainless steel turkey baster and suck out as much molten plastic as possible. The oven would then go to 1000˚ for an hour and be fully burned out. Because burn out in an oven is pretty nasty smelling at its peak and I can’t really recommend it as a best practice. However, I just became aware of Moldlay– a 3D printing filament designed for lost wax casting. It’s expensive but I would like to check it out.

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Mold mid burnout

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Molds at 1000˚F after burnout

From there I tried two basic approaches to casting into the plaster molds. The first technique involved putting molten glass from a furnace directly into the molds. The second involved cooling the molds back down, packing them with chunks of crystal glass, then firing them to melting point. Each techniques has its strengths and weaknesses.

Lost PLA Kiln Casting Technique 1- “Hot Glass Lacrosse Casting”

Since buying crystal to kiln cast with is very expensive, I was trying to be more cost effective by using the readily available furnace glass to cast with. Basically, after the mold was burned out I would soak it at 1000˚ for several hours to burn out any chemical water, and then we would ladle glass directly into the molds. I found that even after I soaked the molds 10-12 hours at 1000˚, the chemical water in the plaster would still cause the glass to bubble up as we poured the glass in. We then resorted to a technique we called Lacrosse Casting. I would gather a ladle of glass, then dump the ladle into a second ladle someone else was holding. They would rock the ladle side to side so that the molten glass skinned up on the outside a little. They would then dump that back into my ladle and I would go to the oven and gingerly drop this “hot tamale” of glass into the mold. The center of the glass was still quite hot but the skinned up exterior was less likely to bubble. Unfortunately the molds are quite fragile and this can cause damage if there are a lot of delicate details to the mold. After the mold was filled, the oven would be sent up to about 1500-1600˚ to make the flatten out and flow into the mold. As soon as the glass flattened, the oven was crashed back down to under 1000˚ and an annealing cycle began.

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Passing off ladles full of molten glass in order to cool the exterior of the glass before dropping it in the fragile molds

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The 2300˚ “lacrosse” pass

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Dropping glass into the mold

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Crashing the oven after it reaches 1600˚F and the glass has flattened out

Issues with this technique

  • This process takes a lot of time! I was casting forms that took 2+ days to print, then there was mold making, casting and annealing.
  • The plaster molds are extremely fragile and can easily be damaged by the glass as it is dropped in the mold. This results with imperfect castings that often have bits of plaster encased in the glass.
  • If the ladles are not very clean, the glass will often have veiling from the ladle surface. Bubbles are also often introduced resulting in a very bubbly glass. In my case I liked the underwater look this gave.
  • Devitrification is a crystalizing of glass that happens at approximately 1200 degrees, making the surface of the glass fog up. Soda lime glass (Spruce Pine batch) is particularly vulnerable to this. In my case, if there was not enough radiant heat above the top of the mold and it took too long for the oven to heat up for the glass to level out in the mold, the surface would fog up.

Sample Castings (Unfinished work)

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Death (work in progress) 14″x 14″x 6″

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Creation (work in progress) 14″ x 14″ x 5″

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Untitled work in progress 14″ x 14″ x 4″

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The Gates of Heaven 24″x 19″x 5″

 

Lost PLA Kiln Casting Technique 2- Kiln Casting

The issues with molds being damaged by hot glass and devitrification lead me to acquire some crystal to kiln cast with. Casting crystal is expensive and usually formulated to not devitrify so in general this technique delivers more optically pure castings. I tried two glass formulas for kiln casting; Uroboros Glass’ system 96  and Schott optical crystal.

After the mold is burned out, I would let the oven slowly return to room temperature so I could carefully vacuum it out and pack it with chunks of glass (My glass came in large tiles so I cleaned the surface with alcohol and then used a torch to shatter them.

Bang! #glass @wheatonarts

A video posted by fredini (@fredini) on

The small chunks could then be loaded in the mold, and the oven slowly brought back up to about 1550˚ until they melted in completely and the worst of the bubbles came to the surface. At that point the oven was crashed back down to under 1000˚ and the glass is annealed (slowly brought to room temperature).

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Loading chunks of crystal into the mold

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Close up of mold and crystal chunks. I like how the mold picked up the layer lines from the 3D print.

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The oven is ready to be heated back up

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At about 1550-1600˚F, the glass is molten and flowing into the mold

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Its a delicate balance how long to keep the mold hot. You want to get the bubbles to rise to the surface, but also want to stop before the glass begins to devitrify and fog on the surface.

  • This technique definitely yielded the best casting results for Lost PLA
  • More expensive- both in the time consuming process, oven time and  most significantly the cost of the casting crystal
  • Devitrification can still be an issue, depending upon the glass used
  • The final casting still requires extensive grinding, polishing and finishing work
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Angel/Mermaid (work in progress) 14″ x 14″ x 6″

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Funny Face (work in progress) 14″ x 14″x 6″

Hot Glass Casting into CNC milled graphite molds

I quickly realized that the lost PLA technique was time consuming and disconnected from all the excitement and spontaneity that I associate with hot glass work. Lost PLA castings also required extensive work divesting from the mold, then grinding and polishing. I had long wanted to experiment with CNC carving as opposed to 3D printing, and set out to experiment with milling graphite to create reusable molds as a more cost effective approach for casting glass with.

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CNC milled graphite molds for glass casting; rough pass carving with 1/4″ endmill, finished mold cut with 1/8″ ball mill, molten glass in the mold and annealed, cooled glass casting

I decided to purchase the Inventables XCarve  because it is an open source CNC machine, and I wanted to support Inventables great work in making CNC software more user friendly. I opted for the 1000mm version with the heavy duty Nema 23  motors and Dewalt 611 spindle which has enough power to even mill aluminum. I had a lot of trepidation about building a kit as some of the 3D printer kits I had built in the past were not well documented, but Inventables documentation was excellent and it worked pretty well right off the bat. A few support calls and posts on the message boards got me through the few small hiccoughs that I did encounter.

However, I was concerned about milling graphite as the dust is electrically conductive. If that dust got all over as I was using the machine, not only would it make a mess, it could also fry the Xcarve Arduino controller, and even the laptop driving the setup. I had no choice but to rig up a robust dust collection system. I ended up buying a dust shoe from KentCNC to mount around the spindle (Yes, I could have made my own but was running out of time at Wheaton by then). This then attached to a Dust Deputy cyclonic dust collector and a shop vacuum. The result was a powerful dust collection system that captures nearly all the graphite coming off the spindle as it cuts, and 95% of it ends up in my new favorite tool, the Dust Deputy.

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The newly assembled X-Carve, still in need of some wire management

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Unlike 3D printing, CNC milling has the machine doing multiple passes. Shown here is the rough pass, done with a 1/4″ endmill.

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The finished mold, cut with a 1/8″ ball mill

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The big test… Trying out the mold for the first time!

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Torching the glass as it sets up in the mold

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It looks amazing!

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The final result- a cast glass tile from a mold that will stand up to hundreds of castings!

Coming out of the last year of experiments, I’m most excited about this process as it has a lot of potential for small run computer designed glass objects and custom tiles for architectural use. There are some design restrictions in that molds cannot have undercuts and the Xcarve can only cut about 2 1/2″ at the deepest, but because these molds can be quickly and comparatively cheaply generated and used to create cost effective editions, I think this approach has a lot of promise. I look forward to continuing to experiment with these techniques as I share them with my class this June at the Pilchuck Glass School.

 

TaDDDaa! A Class in Digital Processes for Glass Casting at Pilchuck Glass School

Kahl,Fred-Image-10I’m please to announce that I will be teaching a class at the Pilchuck Glass School in June of 2016. The class will cover a lot of the digital to physical techniques that I have been working with over the last few years, particularly this past year with my fellowship at Wheaton Arts Creative GLass Center of America (Stay tuned, I will be publishing my finding soon).

The intensive 3 week class will take place in June of 2016. Pilchuck’s session 2 this year has a theme of Play, and we certainly will be playing with ways of bringing the 21st century to glassmaking’s 19th century traditions.

TADDDAA! 
May 31- June 17
3-D Modeling & Printing, Lost PLA, CNC, Kilncasting, Hot Casting

Digital sculpting and 3-D printing tools allow artists to visualize prototypes, manipulate scale, and replicate with precision. This course will introduce an assortment of tools including Zbrush (an organic sculpting software), 3-D printers, and 3-D scanning methods of photogrammetry and structured light. Students will learn to scan, manipulate, and print objects and ultimately kilncast and hot cast them in glass. This class is for glass artists who wish to explore digital fabrication and 3-D artists who wish to explore glass.
http://pilchuck.com/summer_program/courses/session2.aspx

The class will cover:

  • 3D Modeling with Zbrush
  • 3D Scanning with structured light and photogrammetry
  • 3D Printing
  • Moldmaking
  • Glass kiln casting with lost PLA
  • CNC milling of graphite molds for hot glass casting

It’s going to be an awesome class and I’m looking for two teaching assistants. Applications for TA’s are due February 3. I would like to find one TA who is well versed in 3D modeling and 3D printing (its a + is you own or have built a 3D Printer), and another who is familiar with glass kiln casting. Please help spread the word!

Scan-A-Rama 3D Portrait Studio 2015 Year in Review

Before the year ends I wanted to write about some of the events I was able to be a part of this year with the Scan-A-Rama 3D Portrait Studio. I had a spectacular year of making 3D portraits for thousands of people at a slew of events that included talks as well as scanning events at the Innovation Loft,  Midwest Reprap Festival, Newark New Jersey, Westport ConneticutBay Area and New York Maker Faires, at Pepsico’s Executive World Summit, and Theatre Bizarre. I also spent the year on an artist fellowship at Wheaton Arts’ Creative Glass Center of America in which I innovated and explored methods of glass casting from digitally designed objects. Stay tuned for more on this- I will be posting the findings from this fellowship in January (I am just wrapping up there now). Finally, I went out to Seattle and set up a bot lab at the Pilchuck Glass School, where I will be teaching a class TaDDDaa!! in June of 2016. The class will cover techniques of glass casting from a digital workflow that includes 3D sculpting, scanning, printing, and CNC carving. If this list isn’t impressive enough for you, I also had two amazing corporate gigs in November that I’ve been meaning to write up- The first being at Google of their internal user experience conference; Google UXU, and the second for Pfizer at their Excelerate innovation conference!

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Google’s UXU is an internal conference for the company’s entire UX ladder to meet up, compare notes on best practices, hone skills and get inspired to create some of the world’s best digital products. I was honored to be invited to come out to the Googleplex and deliver the conference’s opening keynote address, one expanded from my talk at Bay Area Maker Faire about the History of Technology as Entertainment that included my work on recreating Luna Park with 3D printing, and ended with some conjectures about 3D printing and what will happen when hot rod culture gets a hold of self driving cars. Was the talk well received? Here’s what one attendee said:

https://twitter.com/rachel_inman/status/661625799171174401

Right to left: Speaker Corey Pressman who gave a great talk about poetry for robots , Speaker Stella Grizont who talked about the science of happiness, conference organizer Thea Kluge/Carter and myself

Right to left: Speaker Corey Pressman who gave a great talk about poetry for robots , Speaker Stella Grizont who talked about the science of happiness, conference organizer Thea Kluge/Carter and myself

The second day of the conference I ran the Scan-A-Rama 3D Portrait Studio at their mixer and created a number of great portraits for people

The second day of the conference I ran the Scan-A-Rama 3D Portrait Studio at their mixer and created a number of great portraits (Click to view larger).

November was busy! I had barely returned from the Googleplex when Pfizer’s Excelerate conference began and I spent two days making 3D portraits of some of the movers and shakers of one of the world’s largest pharmaceutical companies. I even made a portrait of the CEO, Ian Read!

Here I am with Pfizer CEO Ian Read!

Here I am with Pfizer CEO Ian Read!

Ian Read's raw scan

Ian Read’s raw scan

The cleaned up scan ready for printing

The cleaned up scan ready for printing

The final print...in Pfizer Blue!

The final print…in Pfizer Blue!

2015 was an amazing year for me. I can’t say I got rich, but as the first year out on my own doing what I love without working for someone else, I think I did pretty well for myself.  Just writing it up now, I realize that Fredini Enterprises has done some great work… and there’s a lot more where that came from! I have a lot of exciting things in the pipes for 2016 – new products, artwork, inventions and more, so stay tuned.

Happy New Year Everyone!

Scan-A-Rama 3D Portrait Studio at Theatre Bizarre 2015!

Its been a whirlwind year and I have completely neglected documenting all the things I’ve been up to, so I’m going to make a push in the next month to write up everything, starting with this year’s pilgrimage to Theatre Bizarre, Detroit’s amazing masquerade ball held in the world’s largest Masonic temple. Last year, I brought the Scan-A-Rama 3D Portrait Studio out to capture some of the party’s most outrageous visitors and this year I succeeded in getting some even better portraits. Here’s some favorites!

JohnDawnDunivant-printPattyChrisSchorfhaar-print NicoletteAndrewWarczak-print london-print LauraRichardKimmel-print JohnKellySiegel-print JimJaniceLeach-print GaryBasemanJoane-print DanHawley-print CaseyAlisonGies-print AndreaRainer-print VedaRamonGrobbel-print TomCapizzi-print ShannonPeshkopia-Michelle SchphinktieKristen-print SamanthaWaldenmeyer-print RodKammer-print NicoleDerickCasier-print MattLavere-print LouisCharlotteDevaney-print KrystalLehl KarenJohnEnglish-PRINT JosueMaldonado-print JasonLajudice-02-print HeidiCraig-print GoatMan-print GinaEricAckerman-print ErinSanders-print DownAClown-print DanaMccoms-print CoreyMichaelBauser-print ClarkAimeeEagling-print Chainsaw-print BrettCarson-RubberChickenMan2 AngelaCharlieThurman-print AngelaBrendonDoran-print AlexLeal-print AlexandraominicReisner-print

And some physical 3D prints:
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3D Scanning at the Brooklyn Museum

I was recently at the Brooklyn Museum for the opening of the exhibit Coney Island: Visions of an American Dreamland, 1861–2008. Its a great exhibit and I encourage everyone to go check it out! While there, I took the time to take pictures of several objects to use to generate 3D models of a few Coney Island Artifacts, as well as some beautiful architectural details.

This process of photogrammetry  or “physical photography” as I have come to call it involves photographing an object many times from all angles, taking care to ensure that each image is in full focus. Once photographed, software analyzes the image to find the same point in multiple images and generates a 3D model of where in space each camera was. From there, a point cloud and 3D mesh can be generated. Its a laborious process but its a very accurate way of generating 3D models of still objects like sculpture.

Here’s the processed scans:

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Spook-A-Rama cyclops head from Deno’s Wonder Wheel Park (Courtesy of the Coney Island History Project)

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Pegasus Statues from the Coney Island pumping station. (read about these here)

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Bacchus Keystone from the Brooklyn Museum Sculpture Garden. This scan came out amazing, with incredible detail to it!

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Another Great Keystone!

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Telamon (Male Caryatid) #1

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Telamon #2

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Architectural Detail from the Brooklyn Museum Sculpture Gardens

Immortalised in plastic by the great Fredini

Great to see some of my Scan-A-Rama 3D Portrait Studio customers blogging about their experiences!

handmade-and-marina

IMG_20151006_085932 The Schilling Family – as captured by Fred Kahl

IMG_20151006_085636 Paul, Beth & John Schilling – Coney Island

IMG_20151006_085718 Our New York family portrait

IMG_20151006_090049 Marina & Brad Schilling – Portrait by the Great Fredini’s Scan-a-Rama

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We came across Fredini’s (Fred Kahl) temporary studio while walking along the main street in Coney Island during our recent trip to New York. Curiousity caused us to linger on as we checked out the little figurines on display next to a box like contraption. We got talking with Fred who explained that he was creating 3-D images. Having talked about getting a family portrait for  a while now, we decided this would be a perfect way to get something surprisingly unique for ourselves. Plus, with my market stall sensibility I could really appreciate the small time player approach of this portrait creator and take home with us something locally made in New York.

So, if you…

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Detroit : Theatre Bizarre 2015

Detroit fascinates me. Even more than LA, this city seems to exist to showcase the glory of the car. Multi layered highways twist and wind like a giant Hot Wheels set with exits to both the left and right. There’s an energy and vibrancy to the urban decay that’s inspiring. It’s no wonder Detroit is such a hotbed of art and creativity.

It’s here that fifteen years ago John Dunivant began to realize a vision that began in his paintings; a dark world of a haunted carnival and its twisted god, Zombo the Clown. He named it Theatre Bizarre. This once a year party that I like to describe as the “Mermaid Parade of Halloween” began on an abandoned lot in Detroit but has now grown to over 5,000 attendees and takes place in the World’s largest Masonic temple, an impressive sixteen story neo Gothic structure that has never been completed. The building itself is worth the price of admission, just to see the elaborate throne rooms, chapels, drill rooms, ballrooms and theaters that hide within the labyrinthine passages of its walls. The building is a testament to the Masons mastery of construction, architecture and engineering and has to be seen to be believed.

Every year John and the Theatre Bizarre crew transform 8 floors of the space into an elaborate haunted harvest festival. It’s the world of his art come to life. The opulence and intention to detail in the installation is astounding and the building is the perfect backdrop. I had the occasion to meet and get to know John and some of the crew over the last few years, and this past weekend was my second year bringing the Scan-A-Rama 3D Portrait Studio there. Here’s some images from this year.

Detroit Masonic Temple is home to Theatre Bizarre

Every year, 5,000 costumed revelers converge upon Detroit to participate in the spectacle

No bones about it, the decor is lavish!

There are Hundreds of Jack-O-Lanterns everywhere

Tables of taxidermied animals, Jack-o-lanterns, candles, flowers and mountains of candy abound

The Masonic Hall’s barber shop

there are scores of entertainers throughout the space

ornate details on the elevator grills

I ran into Gary Baseman who flew in from LA to check it out

Here I am chilling out with Zombo the Clown

Since no one can enter without a costume, the guests are often the most entertaining part of the night

Here’s John Dunivant enjoying thr fruits of his labor with Burlesque starlet Roxi D’lite

Just one of the many thrones within the Masonic temple

A New Orleans brass band lead the crowd through the building

This year was the “Year of the Goat”

Prints of John Dunivant’s paintings adorn the walls

Elaborate dioramas bring John’s paintings to life

Table setttings in the Fountain Ballroom

The Crowd in the Crystal Ballroom

The insignia of Theatre Bizarre’s secret society hangs on the wall, its all seeing eye looking over the festivities

The heart of the building contains this three story chapel. it is said that the cross marks the actual center if the building and that theres a hidden throne room behind the altar. When someone sits in the thone the cross perfectly aligns with a grate on the wall so that the light of the cross falls upon the person in the throne.

Dioramas in the lobby created by Dante bring the world of John’s paintings to life

A darkened theatre for suspension performances

A red light in the labyrinth of the temple’s hallways

Behind the scenes we saw a museum of Masonic imagery

Elaborate ceiling details

Are these the Knights of Templar guarding the staircase?

Backstage, an army of makeup artists prep Zombo and his minions for the night

So there it is.. Theatre Bizarre n a nutshell. You missed it this year but next year it will run two weekends in October so start making your travel plans now to attend the greatest masquerade on earth!