Saturday, December 5, 2009

Pinball Translite Light Box - The Beginning

Pinball Light Project
Everyone has seen them.. those Pinball Backglasses or Translites framed up on the wall - displayed as art. Some even lit up as if they were still in the game. They look great, but aren't as easy to come by as it would seem.

I've always wanted to have some, and have been collecting some translites over the years (when affordable) to save up for when I would actually under take the task. Well this last month I finally got started. I decided I wanted to light up mine, and I'd start by building at least two prototypes to work out exactly what I wanted.

The first challenge is how to light them. Choices include traditional pinball lights/sockets, mini christmas lights, light ropes, florescent lights, battery powered lights, or new christmas LED lights. The problem is most solutions require AC power. As you can imagine, there isn't always a handy outlet where you want to hang a picture. LEDs due to their lower power look like a real potential with battery power. Rather then trying to build my own light kit, I looked to hack something existing.

I did find some LED light strings powered by AA batteries that claimed 120hrs of light. They did run for 4 days before I turned them off. They just weren't bright enough. Traditional lights used in pins is the most logical idea since you can even mimic the exact lighting used in the games, and with some simple breadboard you could even animate it. However these bulbs would require a transformer of sorts and they put off a good amount of heat.

The solution chosen was to use LED light strings, and then wire them up to some power cord with a switch. I found at Michaels 30 LED strings for $4. A quick test showed that 2 strings lit a translite pretty good, so Prototype #1 would use two of these strings.

The next question was what to build it from? Because the light is not diffused great from LEDs, I needed some space between the translite and lights to lit it evenly. This lead to basically shadowboxes or lightbox designs.

The basic design for prototype #1 is 1x4 premium grade wood arranged on its edge into a picture frame with mitered corners. Grooves would be cut and a 1/4 panel would make up the backpanel where the lights would be connected, and two 0.093 polycarbonate pieces would sandwich the translite in the other groove. The lights would be wired to a switch, and a power cord.

The problem was I had never really tried to build something with these types of tolerances (picture frames) so lots of practice was in order, as well as getting some new tools I didn't have yet.

After spending a few nights experimenting with my new router on scrap wood, and getting accustomed to my compound miter saw I felt up to the task.

Prototype #1 would be built around a William F-14 Translite and be made of Red Oak. It's basic description is
  • 1x4 Red Oak sides arranged on edge into a picture frame with 45deg mitered corners
  • 1/4 wood panel painted white to act as the backboard
  • Two 0.093 polycarbonate sheets to hold translite in a sandwich
  • 1/4 inch groove cut around inside of frame at 1/2 inch from rear edge to hold the backboard
  • 1/4 inch groove cut around inside of rame at ~3/4 inch from front edge to hold the translite
    Mitre edges to be finish nailed and glued
  • 60 LED lights to be stapled to backboard in distributed pattern
  • A lamp cord is wired into a push switch (which is mounted into bottom edge of frame) and then into a power receptical/socket inside the frame. The LED strings then plug into this socket leaving only the power cord exposed and a switch on the bottom edge of the frame

The big problem was, how to build this in a way that could be opened so it could be serviced or have the translite removed without destroying it all. I wanted to be able to remove one side of the frame and pull out the panels. I thought for awhile about a pull out panel like the pins themselves use, but passed due to conerns over getting the sides good enough to avoid light leakage and needing to support the translite better.

My solution was to incorporate a 1x2 board inside the frame which would serve as the top of the frame, the the exposed top would just be set on top of this. This also gave a nice strong board to mount to and keep the frame square. However, once I started putting the mitered frame together with all four pieces, I found getting the eges good required a tight fit, one that a top just lightly secured would not do.

So the 1x2 installed just inside of the top of the frame is actually screwed to both sides and serves as an adjustment to square up the frame and hold it secure. The top piece is then screwed from the top down in an effort to pull the top board down TIGHT against the other frame corners.

Results were mixed on Prototype #1's corners. This is mainly due to my mitre saw being just a tad off. Measuring and getting the saw perfect in less then 1/32 of an inch deviation is very hard.

Here is the top board. The two screws on the side are the ones holding the 1x2 internally and the one screw on top pulls the 1x4 board down into the frame.


You can see the corners didn't line up great.


I pushed on with the best I had. To mount the frame, eye hooks were installed along with picture wire to hang the frame with. Small 1/4 inch notches were cut in the top and bottom back edges to allow the power cord to exit easily. A small notch in the bottom of the backpanel allows the power cord to exit from the insdie of the frame to the rear.

Here is Prototype #1 in it's natural state


I was undecided on a finish, but thinking dark colors would help hide the mitre failures, I opt'd to stain the frame an ebony black. This does help hide the imperfections while still allowing the grain of the wood to show.

But because it was so hard to get my frame even decently assembled with the poor mitre joints, I opt'd to stain the wood while it was still assembled, including the translite installed. I used painters tape to get into the edge grooves and cover the plastic - but somehow I failed and some stain ended up along the top edge in some rather noticable ways :(

Check out the gallery by clicking on the image below for more images of prototype type #1 including some completed shots -
Up next... a cost break down of Prototype #1 and onto Prototype #2

1 comment:

Anonymous said...

Do you build to order?
I can't have pinball machines, however I do collect translites, and it would be cool to get them framed with lighting behind them.