I am building a shaker motor from scratch for use in modern Stern games and I have questions. Does anyone know the part numbers for the 2 pin and 3 pin Molex connectors that hook the shaker up to pinball cabinet connectors? Where is a good source for those connectors?

Looking at the Stern shaker in my ACDC and I am puzzled by the shaker PCB circuit. Why are there two fuses and two diodes? Only one path is used and I don't see how the other path could be used.

I saw the board at PBL. $30 for one diode, one fuse and one resistor is ridiculous! The connectors I am looking for are the ones that mate with the harness in the game. My total cost for this thing (not including the material I will use from my shop) will be about $15 plus connectors to mate with the game harness. Plus it looks like a fun project!

So - are you going to build one? I think this will be fun! I will post some pics when I get it finished.

I looked at PinballLife and they don't sell the connectors I need.

Thanks! That is exactly what I was looking for!

The web page with the homemade shaker was interesting. I want mine to be much better built than that. When mine is finished, I want it to look and perform as good as or better than the factory units.

The "main ingredient" is the motor and I don't think I can get those for cheap anymore. The place I bought them has sold out and I don't expect them to get more stock. I bought three motors and if this 1st one works nice, I will be using the other two to build two more shakers for my other games.
If someone finds the motors for a reasonable price, building more may be possible.

The Pittman motor is not going to work well as a shaker motor. The shaft diameter is too small to handle the loads from the fly weights. You need a motor with dual 1/4" shafts.

The force resulting from a 4oz fly weight at 3000 RPM and a 1 inch CG radius works out to 63 lbs of force. A shaft smaller than 1/4" is going to bend / break! You can use the following to calculate different parameters.

http://www.calctool.org/CALC/phys/newtonian/centrifugal

Those are the same ones I bought.... just a bit more spendy.

I got a little time to work on my shaker today. Almost done! I ordered the connectors from Great Plains Electronics.

One thing I found out today... the shafts on those Johnson motors are HARD!!! I was drilling the recess for the set screw and had to resharpen the drill bit three times for each end of the shaft.

Not finished quite yet. Still need to build the circuit board and the fly weight shields. But the basic shaker is finished and tested. I clamped it down to my work bench and shook my shop!IMG_2202.JPG

Here is one of the side plates. Made these from 0.125" 6061 aluminum. I cut the plate on a radial arm saw ( yes I know they are meant for wood, but they work great on aluminum up to about 3/16" thick just using a standard 50 tooth carbide woodworking blade). I drilled and countersunk the holes on a drill press.IMG_2188.JPG

Here are the fly weights. I used 0.625" x 1.25" brass bar stock (purchased from Online Metals.com). I used a hack saw to rough cut the length, the cleaned the cuts up on the radial arm saw (yes - it cuts brass very well also - just don't try to cut the bar stock off directly - only use it too slowly take shave cuts and true up the hack saw cuts). Length is 1.75" and the axle hole is centered 0.25" from one end. Again, I used a drill press to drill the axle holes and the pilot for the set screw. Before I threaded the fly weights, I slipped them on the motor shaft to use as a drill guide for the shaft indents. I used 1/4-20 x 0.625" set screws and used LockTite to make sure they don't back out.

The most important tool needed to build this is a drill press. You could get away without using the radial arm saw if you don't mind the edge cuts looking a bit rough.IMG_2189.JPG

I did not like the factory weights. They are too thick thus pushing the CG out farther from the motor bearing. Mine are wider but thinner than the factory weights. Mine are also a bit shorter than the factory weights but brass is heavier than steel so the end result is that my fly weights are about 0.8 oz heavier than the factory ones. Which is what I wanted since I want the shake to be less "buzzy" than the factory shaker.

I can't wait to get it installed in a machine and see how it shakes!

If you use the Stern board, you will need two more connectors to hook up the harness and shaker to the board. I think they are 0.156 molex connectors. You will also need the Stern wire harness. I am building my own harness / board so I only need the two connectors that hook up to the cabinet connectors in the game. I can post a pic of my board when I finish it but it is going to be pretty simple. Just a fuse block, diode and 1ohm / 10 watt resistor. Been having too much fun playing Star Trek to work on the shaker!!!

Shaker is finished! Came out awesome! It works like I was hoping in that it is a lower frequency shake - more like a rumble instead of a buzz. Very smooth and quiet also.

Here is a pic of the circuit board and the shaker installed in my Star Trek.Shaker Motor Circuit Board_2471.jpgStar Trek Shaker_2481.jpg

I have had several people asking me to build a shaker for them. Sorry but I am just a hobbyist and don't have time to build these for sale. I tried to provide sufficient information for you to copy the design and build your own if you want. I will also be happy to answer any questions.

RacerRik

Here are the motor specs:

JOHNSON ELECTRIC HC 970 series permanent magnet motor.

SPECIFICATIONS •Voltage 12 DC
•Amperage 0.5 Amps (no load)
•Speed 3200
•Rotation Reversible
•Bearings Bronze Bushings
•Enclosure Open
•Duty Intermittent
•Mount 2 tapped holes on face
•Shaft 1/4" dia. x 5/8"
•Size 2" dia. x 2-3/4"

Sounds good! Please post pics of yours and let us know how it turned out.