Fini.

Big Plex.

For our current exhibit Stories in Fiber and Clay, we had to devise an object mount to support some large platter-style baskets in one of our existing garment cases.

I devised a system where a curved panel could be placed in the case diagonally. The curve is not only aesthetic, but adds to the stability of the unit as well.






















Since I wanted this to be reusable, it needed a system to attach the object mount without drill holes in the panel. I added a series of 3" wide slots along each of the flanges, so a strip of plex could be placed where needed. The strips are expendable, leaving the panel free from invasive work.

The large panels was no problem for our vacuum to hold. The flanges however, had to be held with double-stick tape. I cut a 1/4" wide by 1/8" deep groove in the spoilboard on the inside and the outside of the part outline. Its purpose was two-fold - it served to aid in tape placement and provided a space to insert a screwdriver to pry the parts off the table without damage.

Next post I'll show the finished product.

Darwin Complete.

Here are a few overview shots of the Darwin exhibit that opened Friday 10/9 at the Sam Noble. Generally we have 2 years to plan and execute such an exhibit. We turned this one around in 3 months.


To complicate matters, our graphic designer left for grad school during this period and we had to conduct a search to find a new one. I am happy to report that we were successful and the new recruit was able keep the project on-track.



Needless to say, I am extremely proud of my staff and the quality/quantity of work they produced for this exhibit.


Time to start working on the next one.

First peek at the Darwin exhibit.

Here are a few shots items made with the 'Bot for the Darwin exhibit that opened on Friday. The exhibit features all of Darwin's publications as first editions, courtesy of OU's History of Science collection.






All of the books are housed in casework that has mill work based upon a "shanty" feature from the HMS Beagle. This example houses "Origin of the Species." With the exception of the tubular vitrine and a extruded aluminum armature, all details were produced in-house with the ShopBot. Each case features an ABS deck, case furniture constructed from acrylic sheet and solid surface counter-top material, as well as the MDF sidepieces as pictured here. The casework is reusable - the sidepiece can be themed to match the exhibit, or a generic maple version that blends with our existing cases can be used.









Here is a marine iguana from the Galapagos housed in a plexi tank filled with an alcohol solution. Bottom base is solvent cemented into tight-fitting groove. The lid was machined with a larger groove to accommodate the application of a low VOC silicone. A series of vent holes were placed in the groove to allow for the silicone to neatly ooze out so the lid could be easily assembled.



What seems like some simple case furniture that bisects the space is actually an attractive gentle curve. This feature is not just aesthetic - the curve give the assembly great structural integrity using a relatively thin sheet of material for the divider, while the cap on top makes the cross-section similar to an "I" beam.

I'll post some more photos of the completed installation later this week.

Signs of Change

We had an emergency. A person unnamed requested that we fabricate a sign "Butterfly Garden Under Construction" lest the public mistake the area for alien crash site.






















Not bad for a scrap piece of Plexiglas and 1.5 hours.

Location, Location, Location!

Our department was tasked with building a portion of our new Orientation Gallery that featured a series of panels mounted on a solid with a cross-section of an equilateral triangle. These spun on an axle, allowing the visitor to rotate them to complete a puzzle or have a question/answer display.



How to get the faces to locate consistently? The plans by others called for each "Trilon" to use a spring-loaded "bullet" that would locate in one of three dimples on the end of the "trilon."

This was problematic for a few reasons:

• The "trilons" would not locate correctly 75% of the time.
• The mechanisms would be subject to extreme wear.
• This arrangement might work is there were only two on an axle, but there were sometimes as many as four. No clearance for this device in "trilons" 2 and 3.

Our solution was to machine a set of UHMW rings that would be press fitted with series of rare-earth button magnets. One formed the end of the "trilon", the other was affixed to the axle with a shaft collar.

Polarity was arranged such that when a "trilon" was positioned at 0, 120, or 240 degrees the magnets attracted. When located in between these angles the magnets repelled. The "trilons" were assembled as a unit within a frame and placed on a flat surface - aligning the faces to that plane. The cap screws on the shaft collars were then tightened.

Witness!



This mechanism has no moving parts other than the bushings that support the "trilons." I am hoping for the device to have an extremely long and trouble-free life.

The Practical Side

Life with the ShopBot is not always glamorous. In addition to the design and fabrication of exhibits, our department provides services to the other departments. Here we are using the ShopBot to help our Vertebrate Paleontology collection by making dozens of poplar blocks that hold small glass vials. These vials might contain tiny bones of ancient mammals, scales, or possibly teeth.

In the past these have always been done by a volunteer on a drill press. Now that person is relieved to take on a task that might be a little more exciting.