Adjustable Prismatic Square

This small square was my first ever toolmaking project. I wanted a small square to use when squaring blocks in the mill. There wasn't material available to make a one piece square, and I'm still unsure about how silver soldered machinists squares are ground on all sides after assembly. So, the base and blade would have to be two pieces, and why not make them adjustable. I didn't go for a traditional rectangular blade like often seen in combination squares because grinding such a thin part would be very challenging, and grinding the mating slot nearly impossible.

Instead I used a square profile blade clamped at 45 degrees. This allows for easy clamping with the clamp remaining withing the edges of the base. The clamp is spring loaded so it loosens easily. The blade is made from a M2 HSS tool bit and the base is 1095. Its a fun little quirky square. I didn't do any formal design for this; no sketches even. As a result the proportions are a little clumsy but that doesn't effect its use.   

Close up of clamp with blade in a middle position

Small relief for checking an outside corner

Stainless Steel Clean Room Pressure Vessel

This was a job for our micro-electronics manufacturing clean room on campus from about two years ago. The previous tank was made of 1.5mm 304 stainless and would balloon out with applied pressure. The clean room tech designed a new tank made with 6mm walls and asked us to build it. All the parts were cut on a water jet with a few machined fittings. The main labor in the project was all the welding.

Every seam was TIG welded inside and out. I first welded the bulkhead rim on to the front panel inside and out. This significantly bowed the plate, so I had to flatten in on a hydraulic press. From there it was standard fillet and butt welds, with many in the confines of the tank. The only seams not welded inside and out were the ones joining the final back plate to the main body of the tank. The bulkhead opening in the front was just too small to reach in and weld. The designer had thought of this and had made the back plate slightly larger to allow for a double pass of weld to attach it. After all the parts and ports were welded, the sealing surface of the bulkhead was milled to ensure flatness.

This was a really fun project because it challenged me to do more non-dominant hand welding. I was reasonably proficient using my non-dominant foot to control my pedal, but only had limited experience with welding left handed. In total I laid over 7m of weld, at least 2 of which was left handed.

One Day Build: Gale Crater Topographic Model

This project was inspired by a kick starter project I found where backers were funding large scale models of the moon (500 mm dia.). The models (which were castings of a high quality 3D print) looked stunning, especially when lit. Poking around out of curiosity, I found NASA has a substantial collection of 3D resources available here including 3D models of spacecraft, satellites, asteroids, comets, and Lunar and Martian surfaces.

I decided to carve a small model of Gale Crater, the current location of the Mars Science Laboratory. The model from NASA had a 3x vertical exaggeration, which I reduced to 2x. Made out of a scrap of PVC, the model is around 200x150 mm. It ran on a machining center overnight and took an estimated 16 hours. It was supposed to run faster, but motors on this machine are very low torque, so the feed rate is dynamically throttled to ensure the axes won't overshoot. All mesh editing and programming I did in Fusion360 and it ran on a Trak 2 Op.

As a result of mesh reducing, the model has a beautiful, faceted effect