About the cabinet

I based the design pretty much on Rick Schieve's multigame cabinet. However, he simply took a Xenophobe, stuffed a 25" monitor in the head piece, and cut out the front for doors and shelving, and dropped on a custom control panel. Now this was nice and dandy, but he had to then build an entirely separate multigame cabinet for his vertical games. I wanted the best of both worlds.

We took his basic design, and Rick talked about all the things he'd wish he had done. The things we fixed included moving the power supply to the upper part of the cabinet above the boards so there would be more room for boards and easy access to adjusting the +5VDC, making a deeper control panel to support things like analog joysticks and such, and left some space in between the doors and shelves for the JAMMA harness.

I told Rick that I wanted a rotatable monitor so I could play ALL games out of the cabinet. I first envisioned some sort of round enclosure which would rotate on wheels. I had no idea how, but I gave the general idea to Rick in a few sketches and we worked the idea together into more practical options.

First, we took careful measurements of the 25" monitor. We figured out what size the box would have to be to house the monitor, with the bottom piece of the box being a large 36" diameter circle. We wanted to use something that would be fairly strong at 1/2". If the wood was too weak, it would develop divots from resting on the wheels, and the edges might splinter. We ended up using 1/2" 9 ply baltic birch. To this date, I’ve had no problems with it.

In order to mount the monitor in an essentially open box, 1 1/2" by 1 1/2" strips of wood were added internally across the top and bottom of the box towards the opening to support the monitor mounting flanges. The monitor was held in place by wood screws going through the flanges in to the wood strips.

We then cut a square out of another 36" diameter circle. When we designed it, we didn't want to lose too much area out of the middle of the circle as these four corners might end up being weak spots where the wood might split or crack. So there is about 3"+ between the inside rectangle and the outer edge of the circle. We placed the circle with the rectangle hole on top of the box, and mounted it to the box with joints behind it for support. But before we mounted it on there, we made a little picture frame style set up around the monitor opening. You see, the tube face actually protrudes past the monitor flanges, up through the opening of the box, so we needed to build something extra to allow clearance for the tube, and something to hold the tinted glass. One of the sides of the frame is removable (3 screws hold it in place), and a piece of tinted glass can be slid into the frame, taking care to make sure the glass will clear the protruding tube (just barely). A hole was placed in the center of the rear circle for monitor wires to be fed through, and in the sides of the box there were two rectangular holes cut, and vents were mounted there (so the monitor could breathe some). It would be possible to place a fan in the box also, but I never got around to it. Also, this particular monitor has a satellite board which has the monitor controls on it. I wanted to be able to reach these from the front of the game, so on the top of the monitor above the frame we made a 4" x 2" x 1" deep cut out in the wood and placed the controls there. I then fashioned a small metal door with a hinge to conceal the controls behind it.

The next part was to interface the "Wheel of Fortune" to the cabinet. We chopped the head off the Xenophobe cabinet. The part of the cabinet where the head was resting is actually sloped towards the back, so we cut some boards to the right angles, and made two mounts that the monitor wheel could rest on.

We need to build two "rails" which the monitor could turn in. To do this, we took rods and placed them apart such that the monitor wheel would not fall out, and that the monitor wheel would just barely clear the cabinet. We then took some small pieces of plywood, sandwiched them around the rod, and ratcheted them down to the mounts. On the end of each rod, we mounted two wooden wheels which would hold the monitor wheel in position. However, we needed something which the monitor could spin freely on. Rick had some old broken dolly wheels, and drilled out their centers, and sandwiched them between two wooden wheels. After making sure the placement was correct, we drilled holes and dropped pins through the rod to keep the wooden wheels from sliding around, yet let the rubber wheels spin freely.

The entire head piece rests on these 4 rubber wheels, only attached by the monitor harness (power and signals).

Rick then cut a nice "L" shape on each side of the cabinet to rest the custom made control panel on. He pretty much stole the idea from the modern Bally/Williams cabinets like NBA JAMs, MK, etc. The control panel is then held in place by 4 wood screws. Of course, large holes are cut away at the bottom of the control panel box for wires to get there, etc, but we couldn’t cut away too much otherwise it would have compromised the strength of the control panel.

Four 7"x9" holes were cut in the top of the control panel to drop in 8x10 control pods. I had many ideas of how to implement keeping the control pods in place and yet have them easily removable, but eventually I settled with just having them attached with screws which drilled into t-nuts mounted in the control panel. A large hinge was added to the front of the control panel to allow access.

To support additional players, voltages, speakers, etc, I used Rick's pre-defined JAMMA+ standard. This meant that Rick and I would be able to swap games and use each other’s test harnesses, which would be a plus.

I used two power supplies, and here is the reason: when hooking up games that are not standard JAMMA, you need to make a harness for the game that converts their wiring to the JAMMA standard. However, these older games can be very picky about voltages. I noticed on the power supplies that I had that if you adjusting the +5VDC, the –5VDC would in turn adjust also, and vice versa. So instead, I put in two power supplies and used the +5VDC and +12VDC from one power supply, and the -5VDC and –12VDC from the other power supply. I then attached their grounds together, and now I can adjust the +DCV separately from the –DCV. However, I also have a cross over switch in the event that one of the power supplies blows (which might and has happened when testing JAMMA harnesses which weren’t wired quite right. Also, I used the +5VDC off of the negative supply to run the coin/credit lights on the front of the cabinet. All the wiring leads to a power terminal strip right under the control panel, and the +5VDC has a 7 amp fuse on it. Inside the cabinet, there is a service outlet for soldering irons and such.

I cut out a large square from the front of the cabinet to put in some shelves and mount some doors for easy access. Inside the doors, I can access the test and service switches, mono and stereo switches, the voltage controls, and the interlock switch.

In order to move the cabinet, I simply disconnect the monitor connector and unscrew 4 screws holding the control panel down, leaving me with three managable pieces. I usually roll the monitor wheel where ever I want it to go :-). The base is extremely light without the control panel and head piece. The only problem is that I am not able to mount and unmount the head piece by myself because it is so large.

Things I would change with my design: I originally tried to put a universal sound amp in the cabinet that I could switch over depending on if the game is amplified or not. This would allow me to have a single volume control, but there are were so many different audio configurations to take into account that I abandon this and just went with a amp circuit that I could transfer from boardset to boardset. I am working on adding a voltage meter to the cabinet so I don’t have to pull out my voltmeter whenever I want to adjust the +5VDC (which is almost never). I probably would have made some changes to the power block by moving the power closer to the harness, and make the adjustments on the power supply easier to reach. I originally designed in a fold out or pull out table so I would have something to rest boards on that I was working on, but I couldn’t come up with anything workable.

Also, might I point out that this cabinet is about 6'6". This is fine for me, being I'm 6'4", but I think shorter people would appreciate moving the control panel hinge to the rear of the control panel, and maybe put the latches on the sides of the control panel.


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