TZ Slot Machine How-to

Ok, yeah, this is already hogged out for the ball and drilled for one of the LED's. Sorry! I didn't think to start documenting this project until after I had already started. So, sue me :) To get to this point is a simple matter of grinding the rivets off the back cover plate and popping it off. Mine was metal, some are plastic. These are pencil sharpeners to begin with, by the way :) I used a water bottle cap as a template and marked the opening for the ball with a sharpie. I clamped it in my vice and drilled small holes near the sharpie line and snapped out the waste. I used a Dremel with a sanding drum to remove the rest of the pot metal (zinc) out to the black line. Took a half hour altogether. The LED hole is 3/32" to fit a 5mm LED. I didn't like the antique bronze look so I sprayed it all gold.

Here you see the hole on the left I drilled for the wire to come through. You also can see the yellow 5mm LED. I had to file the plastic flat just a bit to get it in there. That worked out great for holding the LED legs where I wanted them anyway.

LED from the front.

I drilled out the two corners at the top and tapped 6-32 to hold the back plate on. I also drilled 4 holes in the bottom and tapped 6-32 as well for mounting. You'll also see I'm bending the legs of a 3mm superbright white LED to light the score reel drum.

Use care when bending the LED legs. They won't take bending more than a couple times before breaking. Needle nosed pliers required.

Heat shrink tubing on the LED legs and glued in place with superglue gel. Reel drum test fit for interference. Looks good!

I used an old 4 wire (2 line) 26 gauge phone cord for wiring. Compact and somewhat flat. Notch the back plate so when installed it holds the phone cord in place but without cutting into it.

Two wires go through the hole I drilled earlier for the upper yellow LED

Last bend, getting the legs out where they will be soldered to wires.

Curl the ends of the wire to loop around the legs, a little solder and you're good. A drop of super glue holds the LED perfectly but easily removed later if needed. Clear acrylic mounting plate to the left.

Solder the other two wires to the lower LED.

Pop the reel drum back in and spin test. Good!

Place back plate on and screw down with two 6-32 machine screws (also painted gold). Notice how the plate acts as a strain relief for the phone cord. A plastic plate may not be rigid enough for that, I don't know, sorry.

Seen from underneath. Note that the back plate has legs molded to it that hold the drum in place. Don't break or cut those off when modifying to allow ball passage.

Now for the hard part :) The mounting plate. I tried making one in PETG and Lexan but they were not rigid enough to hold the slot machine suspended in space (which it needs to do) Acrylic worked great though. I used some scrap 1/8" thick stuff. Use the wireform ramp as a template to make the base plate. I made the slot machine sit too close back to the "wings" you see with the screw holes. I should have moved it forward about 1/4" from where you see it here. This would allow the wiring to fit a little easier. No matter, I had what I had and it worked fine. The other thing you'll need to make is spacers in the same acrylic but you'll probably need to make pairs in different thicknesses for trial fitting later on. Obviously you want the spacers drilled to match how you drilled the slot machine bottom and make them just a bit wider than the base legs of the slot machine. The blue plastic piece in the pic is what you're shooting for.

Time to do the highlight painting! If your eyesight is starting to get bad at closeup stuff a headband magnifier is great for this. A steady hand helps too :)

Paint the bandit arm and glue in place.

A mounting we will go! This is the S.O.B. part. Trial and error getting the ball to go through and yet touch the drum enough to spin the reels (albeit backwards :) Here I ended up with a 1/8" base that attaches directly to the wireform ramp. A hex post spacer is omitted here for simplicity in taking off and putting on the shims between the slot machine and the base. I started with 1/8" shims and had to add an even thinner shim to each side. I used packaging plastic to make the thinner shims but they are invisible in this pic.

A shot from behind. You can see the phone cord will just fit between the (missing) hex post and the ramp side.

Now we test fit with the lamp and flat plastic in place. Just right!

Time to wire it up! Ok so I used the red & black wires for the white 3mm LED and I want this connected to the GI lighting. I used a 150 ohm 1/8 watt resistor (brown-green-brown) in series, This is soldered to one side of a GI lamp socket as shown here. The black wire goes to the opposite lamp socket leg. At this stage I'm just testing but later on I'll make a connector for easy removal and I'll heat shrink the resistor to the wire.

For the yellow LED we want it to light up in time with the yellow lamp on the flat plastic below the slot machine. The LED I used is an older standard 5mm LED. The resistor for this one is 220 ohm (red-red-brown). I got smart and realized a fantastic way to splice into a harness is by using an IDC connector! Why not? I have bazillions of them saved from all kinds of things and at least half a bazillion are 2 position connectors. So I punched one down into the two wires that go to the controlled lamp for the slot. Cool! Easy! CHEAP! :) Now I simply inserted the green wire into one position and the yellow wire with resistor into the other and powered up for test. Worked great so on to finishing the connector.

I also have at least a bazillion of those PC board header pins in a black snap-off housing. Snapped off two positions (they are .156 spacing, by the way, to match the plug) Now, be smart and put your heat shrink on BEFORE you start soldering. Don't ask me how many times I wasn't so smart. Now solder the resistor to one pin and the green wire to the other. Slide the heat shrink down and shrink it. Done! If the LED doesn't light, don't panic. Just flip the connector over to reverse the polarity.

See? Solder the wire and resistor, slide one heat shrink down and shrink...