In the late Spring of 2012, I made a picture frame as a gift for the Swarthmore Engineering Department’s machinist, Grant “Smitty” Smith. In his office, Smitty has a photo of him from much earlier in his career, standing next to a gigantic, 4-story universal testing machine that the Engineering Department used to own. It’s a great photo, but is much the worse for wear – it’s dog-eared, torn and browning. I wanted to make him something in the shop as a thank-you for teaching me and generally putting up with me over the past 4 years, and I figured a machined frame for his photo would be a fitting choice.
The frame is machined from 2.5″ x .5″ 6061-T6 aluminum bar stock. I cut all four pieces to length (without beveling the corners) and milled the correct profile into each. I then cut the corners at roughly 45 degrees on a bandsaw, and sanded them until they fit. The pieces are joined at the sides using socket head cap screws, which fit through the side members into threaded holes in the top and bottom members. The glass, photo and backing are held in place by aluminum “push plates” made from 1/8″ x 1″ aluminum bar stock; the push plates are tightened down on the glass, photo and backing by the socket head cap screws visible on the face. Finally, I stamped and installed a plaque on the base of the frame.
Overall, I’m quite pleased with the final effect of the frame. If I was to repeat the project, I would improve it in 2 primary ways:
- Profile all parts simultaneously: I didn’t take enough care to ensure that the dimensions of the side parts were exactly identical, especially when cutting the chamfers on the front face. Although it didn’t seem like it would make that much of a difference in the final product, it absolutely did. If I made a frame like this again, I would try to profile a large enough piece of stock to make all four frame components, with an extremely rigid work holding system that supported the entire length of the part. Even with the relatively short lengths of the parts I was working with here, I still wound up experiencing some significant chatter that produced interesting, if unwelcome, patterns on the ends of the frame components.
- Precisely machine angles: In retrospect, I should have set up a rotary table or other jig to cut the 45 degree angles. The belt sander did a passable job, but the risk of damaging the finish or other parts of the frame make it less than ideal to use.