Introduction: Pinball Coffee Table
This is a coffee table built from the playfield of a pinball machine. It is pretty easy to build and best of all, it lights up! It was inspired by a bar in Seattle called Shorty's, which has tables similar to these in its booths. My girlfriend and I both love pinball. We met at a pinball convention, and we both regularly attend pinball events and tournaments, so this was the perfect gift for her as well as being fun for me to build.
Step 1: Materials List
Here are the materials you will need for this project
1 pinball playfield
2 side pieces of wood cut to fit
2 end pieces of wood cut to fit
Moulding to be used for the top to hold the glass on
Tempered glass cut to fit
Four legs and hardware to attach
Screws and nails
Step 2: Acquiring a Playfield
The first thing you need is the playfield from a pinball machine. This is the painted wood that the ball rolls around on as you play. Playfields can be bought with all their parts attached ("wired") or with all the parts removed ("unwired"). For this project you will want a wired playfield. The electronics are necessary in order for it to light up, and it just looks a lot cooler with all the parts on it.
Your best bet for acquiring a playfield is Ebay. Search for "pinball playfield" and you will get lots of options. These days it is often more profitable to "part out" an old game to collectors who use the parts for restorations than it is to sell the game itself. A playfield can be as cheap as $50 or as expensive as $1500 plus shipping. Typically the older the game, the cheaper it will be. This will be your biggest single expense in the project. If you don't like Ebay, many areas have auctions of coin-operated games and parts and will often have playfields for sale, although the quality tends to be more questionable. You can also ask at online forums like the rec.games.pinball usenet newsgroup.
When buying a playfield, the first thing you want is something that you find attractive and visually appealing. I wasn't looking for something cosmetically perfect, but I didn't want any big gashes or anything in the paint. You will also want to make sure all the plastic parts (that cover the various mechanicals) are present. If the auction text mentions that the playfield was fully functioning when it was pulled out of its game, then that can be helpful information, although for the purposes of this project, there's really not a lot to worry about functionally.
The playfield for this project was a Williams Lucky Seven from 1978, which I purchased off Ebay for $80 plus $50 for shipping (they are heavy!)
Step 3: Building a Frame
Once you get your playfield you will need to measure it so you can figure out the wood you need. Most playfields are a standard size but some aren't so I'm not even going to list measurements here. Just measure yours! The table will probably need to be 8-9 inches tall in order to accomodate the parts hanging off the bottom of the playfield.
It should be noted here that I am not a carpenter, and this was my first major project, so its quite possible that the way I went around this was not the best. I was learning as I went. Hopefully you have someplace more appropriate than your kitchen floor to build too!
I got all my wood cut at Home Depot, a great option if you don't have your own power tools. The sides are 3/4" thick paint grade pine. I couldn't miter the corners because HD wouldn't do that for me, although obviously that is a nicer option if you have the tools for it. I just laid down my sides, glued them with wood glue, and tightened them down with the 90 degree clamps. After giving them a little time to dry I screwed them down with wood screws. If I was to do this again, I would make the long sides screw onto the short sides rather than the other way around. It would mean you don't have a seam showing on the side you look at (although you would have screws), plus I could then use those pressure clamps to hold things together more tightly. They don't make clamps long enough for the long side.
Note in the detail photo I measured 3/8" in (half of the wood's width of 3/4") and lightly scored a line so I would have a visual guide of where the screws go. I did this all over the place and it was extremely helpful. Later you can just sand these out or paint over them.
Step 4: Adding the Ledges
In order for the playfield to lay flat in the box, you need to add ledges on each side for it to sit on. This holds it up high enough to keep the parts on the underside from laying on the bottom. Again, this is just something you'll have to measure for yourself to see where yours should go. I believe mine was about 2.5" from the top. I just used a couple scrap pieces of wood I had leftover getting the sides cut. Marked their position, glued them down and screwed them on.
This is a good time to lay your playfield in to check its fit.
Step 5: Attaching the Base
This step is easy. Glue all around the edges, lay your bottom piece of wood on, and screw it down. I used a jar of pennies to weigh it flat although again, some pressure clamps would have been a lot better. The wood I used for the bottom was a slightly lower grade than what I used on the sides and only 1/2" thick. If I was doing this again, I would set it inside on some ledges and screw it down that way to eliminate the exposed seam on the bottom.
NOTE: Check, check, and check again to make sure you put the bottom on the correct side. The ledges you added in the prior step will be closer to the top than the bottom, and screwing this to the top bu accident would be disastrous. I came very close to doing this only noticing at the last minute.
Step 6: Moulding and Glass
This is probably the most complicated part of the project. I had several requirements here.
1) I wanted a piece of glass on the table like in a real game
2) It needed to be held on somehow
3) It needed to be removable so I could get into the table at a later point if need be.
Measure your glass and get it cut at a glass store, most local hardware stores won't be able to cut a piece this big. Make sure and get tempered glass. It is stronger and far less dangerous if it shatters.
At Lowe's I found some moulding that worked perfectly for what I needed to do. It was 90 degree angle, 1" wide and 1/4" thick. This made it fit exactly right when laid against the 3/4" thick wood. So I measured the moulding and cut it using a miter box. Then I took my glass and laid it on the top of the table. Now I could just lay my moulding against the edge of the table, pull it down flat against the glass and nail it down knowing I had everything just where it needed to be. I nailed down three sides, and attached the fourth side with a single screw allowing me to take side off and pull the glass out whenever I want.
Once you have the three nailed pieces on, its again a nice time to put the playfield back in. slide the glass on, and lay down the fouth piece of moulding to make sure everything fits properly.
You'll notice in the photos that the corners arent quite as tight as they could be. Thats just inexperience and hand tools at work. Its tough to get that stuff really tight. I also split the moulding in a couple places, its really thin and you need to be very careful with it.
Step 7: Pinball Lamp Electronics
You now have everything in place to be able to move to the next step of getting the lights going. However first a few words about lamp electronics. Lamps on a pinball playfield come in two types - controlled and general illumination (GI).
Controlled lamps are associated with rules - they are on in certain cases and off in certain cases. Special When Lit is an example of a controlled lamp. The target the lamp is in front of scores a special when the lamp is lit, otherwise it does not.
General illumination is illumination around the playfield which is not tied to any feature - it is always on.
In my table I used only the GI. By applying power and ground to one circuit you can light up a ton of lamps. Controlled lamps are more complicated, depending on the game you're working on. On older games, they are controlled by relays tied to scoring features. On newer games, they are put together in a matrix configuration controlled by diodes. If you wanted to also light the controlled lamps, you could do so by rewiring them into the GI string, however the specifics of doing that is beyond the scope of this article. There is lots of info out there for those who want to investigate it, or you can again ask questions on rec.games.pinball.
Another suggestion I got at one point was to wire up a string of christmas tree lights and attach them under the controlled lamps. You could also have blinking lights this way. I chose not to go this route though, but it would be fun to try.
Step 8: Hooking Up the Switch and Power
I considered lots of options here. Originally I was going to put a transformer into the table and run a cord to the wall. I really didn't want to though, since this table was meant to sit in the middle of a room. A friend suggested using a lantern battery, and while I was skeptical at first it worked like a charm. The battery I got was 6V, and you could probably get a bigger one for brighter lamps.
The first step in hooking everything up is locating the GI string. Typically GI is located along the edges of a playfield. For instance, at the top of a plyfield between the lanes at the top, under the plastics, there will typically be lamps. These are always GI lamps. Another classic location for GI is under the slingshots (the triangular poppers above the flippers.) Every GI lamp has two wires - power and ground. Follow them around the playfield until you find where they exit in the wiring harness. In the first picture below, you can see where the lamp wiring runs from lamp to lamp before finally exiting in insulated wire on the right.
Pull these two wires, hook one to the + terminal on the battery and one to the - terminal. Your playfield should just light up - that easy! If only some of the GI lights up, then you've got a break somewhere you'll have to hunt down.
Once you know your electronics are right and proper you can install the switch. I got a DPDT switch from Radio Shack although later I realized I could have used a SPDT just as easily. I used a rocker switch that stuck through the wood and screwed down from the back. Unfortunately it was only 1/2" deep, same as my wood so there was no clearance to screw it down. I ended up just sticking it on with some hot glue.
Wiring the switch is pretty straightforward. One thing I added at the last minute was a little holding cage for the battery using scrap pieces of moulding. You can see how I basically just screwed them down around it. This holds the battery in place when moving the table around.
Step 9: Adding the Legs
The legs are probably the easiest thing here. Lowe's and Home Depot have a wide selection of screw on legs, as well as the hardware to attach them. Pick four of the height and style you like, attach the hardware to the bottom, and screw them on. I used 8 inch legs, which makes my table about 17 inches tall all together.
Step 10: All Done!
Hey nice table! Should make a great present for somebody or light up your own house! Here are some changes I would make or consider if I were doing it all over.
1) Pay more attention to exposed seams and work to minimize them.
2) Hook up controlled lamps
3) Try larger battery
I hope you enjoyed hearing about this project. If you build your own make sure and let me know!