Reel Study

[ernie]

I am a newcomer to slot machines, and I hope some members of this forum find the following interest and useful. I started to study the Groetchen mechanism because I knew nothing about it, and I did not understand how the reels functioned or how they interplayed with the rest of the machine.

I still have many questions, and I hope experts and novices alike respond to this post.

With some patience and a bit of finagling, I was able to remove the entire reel assembly (Photo 1). I pulled it apart into three pieces (Photo 2) and studied each piece. First, I noticed two holes. Second, middle and right reels were firmly connected to each other.

I then put these two reels on a smaller diameter rod and clamped one end of the rod to my vise (Photo 3). Rotating Star B caused Reel B to rotate. Rotating Star C caused Reel C to rotate. Obviously something was coupling the two parts together and allowing each to rotate independently.

The Brass Tube in Photo 4 extended through both reels and stars. By loosening all the screws on Reel B (Photo 5), I was able to separate the parts (Photo 6).

Photo 7 shows the outer and inner tubes. I am guessing that the outer tubes are press fit onto the inner tube. Perhaps this arrangement permitted some adjustments to the length and hole alignment for this part. I decided that further disassembly was too risky.

Reel C, with its star still attached (Photo , also has a tube. This tube goes through the reel and its star. In the photo the tube and screw hole are visible. I did not try to disassemble these parts further.

The Pin Holes in the Primary Axle and Left Reel (Photo 9) should align after the axle is inserted through the three reels. At this point I noticed that the reels did not all move freely. Part of the problem was due to friction between the Reel Hubs in contact with one another. Once I inserted a pin though the Pin Holes The Reels were too tightly pressed together. By grinding (just a little) and polishing the surface of the hubs (Photo 10) the problem disappeared.

Finding the right size pin for the Primary Axle was difficult. I tried a variety of tapered brass pins. Eventually, I found that two strands of 0.02" diameter stainless steel wire (Photo 11) worked well. This is not a very elegant solution butt, for now, it will do.

I decided to remove the paper strips from the reels before I put back the reel assembly. I was surprised to find number written on the reel (Photo 12). I have no idea what they refer to or if I need to understand them. Any help with this or anything would be most welcome.

Thanks,
Ernie

[nvmos2]

For being new to slots, you sure dived into this one head first.
It's been a while since I've worked on a Columbia and I never had to disassemble the reel bundle.
The numbers written on the reel are probably a guide that someone used to attach the reel strip to the reel; looks like the numbers refer to the payout for each position.

There is some decent info available for the Columbias;
There is a booklet called "Instructions" for sale on feebay, but it is pretty basic and you are deeper into your machine than that booklet goes and it has no illustrated parts diagrams.

Parts diagrams can be good to get your terminology correct and I find that the name of the part often helps to figure out what it does.
You may want to look for Coin Slot Guide 19.
There is also a good article in The Coin Slot Magazine for January 1982 that covers common Columbia jams and adjustments.
If you can't find them on the web, I can make some copies when I return home in a couple weeks.

[marsonion]

One thing to watch for on Columbia reel bundles that have seen a lot of play and wear: the third reel symbols will start drifting off the payline, slowly climbing upward (if I remember correctly) until you can't tell which symbol is supposed to register. In an advanced case of this growing malfunction, the payouts will be affected. What's happening is, the screw securing the reel casting to the thin brass tube you exposed in your pictures has, through repeated strain and inertial impact from the sudden reel stop, worn the screw-hole in the brass to an oval... and trying to tighten that screw down won't help. So the third reel just keeps migrating a little with each stop, until the payout plunger starts hitting a spoke instead of traveling through the third reel casting as it should on a payout. Last year I bought a NOS reel bundle for a machine that passed the point of no return on this malfunction; in another machine several years back, I pulled the brass tube, roughed it with sandpaper and seized it to the casting with Locktite... I'm not proud of this, but it "fixed" the problem.

The numbers somebody wrote on your third reel have me stumped, too. They would seem to correlate to payouts (three and five for cherries, ten for oranges, etc.) but that would necessarily imply that your first reel has three cherries in a row! In any event, I think the easiest way to dress a naked Columbia reel bundle is to insert a paintbrush handle through the jackpot holes, and then attach the reel strips by lining up the jackpot bars. All the other symbols should then line up automatically, regardless of whatever somebody might've scrawled on the reel castings with a Sharpie.

[ernie]

Hello Marsonion,
Again, I thank you for all your information. The thing I enjoy the most about these machines is their relative mechanical complexity. They are wonderfully complex and yet decipherable. I am learning a great deal, and enjoying it all.
Thanks again,
Ernie

[ernie]

Hello nvmos2,
Thank you for your reply to my post. I have noticed that their is not a lot of information on the Groetchen mechanism itself. I am greatfull for the tips on the Coin Slot Guide 19 and the Coin Slot Magazine. Thanks for the offer to make copies. I will let you know if I am unsuccessful.
Thanks again,
Ernie