Novomat query

[pennymachines]

There's an air valve damper visible in the pictures adjacent to the clock which seems to work in conjunction with (but not instead of) it. I think it won't work without the clock?

Without taking a mech apart, I can't be sure, but think the reels probably do run on ball races. They're very low friction. They're probably the only parts heavier than their equivalent on an American bandit because, as I said, they're cast. This (combined with the cams and struts) gives them plenty of momentum. Reel bundles on "normal" bandits have lots of momentum too, thanks to the adjoining steel discs.

Although a ball race (or roller bearing for that matter) introduces more moving parts, it reduces the area of metal to metal contact and thereby the friction - that's its purpose. Jerry could explain this better.

The first time I played a Gunter Wulff Duomat I thought there must be an electric motor inside because it ran so long.

I see I've misidentified the reel kickers as the brakes in the picture above. The spring-damped brakes are just visible between the top of the reels. I'll correct it shortly and try to add a short video of the mech in action.

Duomat from automatix-club.de

[JC]

Assuming I am the 'Jerry' Pennymachines refers to above, yes bearing races significantly reduce friction - it's what they're for. But this probably isn't the right site for detailed technical explanations. Just consider walking on a floor covered in ball bearings - the feet will tend to travel faster than the body!

Jerry

[operator bell]

Having recently acquired one, I can answer the reels questions. The reels run on two ball bearings. They are zinc castings and very heavy - about 24 ounces (680g) each, so there's plenty of inertia to keep them turning for 15 seconds. The air valve damper next to the clock is attached to the reel spin strikers. It picks them up part way through their stroke, after they clear the reels, and lowers them slowly to the rest position.

This Novomat I just picked up is rather odd. The case coin hardware - the inlet slot in the "Novomat" casting and the reject chute, also a casting - is scaled for a US nickel (just over 0.8 inches). It's not a conversion, it was made that way. There is no way this case ever admitted a coin larger than a nickel. The mechanism is not nickel size though, it has standard 10 pfennig slides that someone tried to sleeve down with rings cut from PVC plumbing pipe. It also has the wrong reels for a Novomat, and the wrong strips for its reels. I calculate its payout percentage as 45%, which is on the low side even for traveling fairs.

On the subject of who wants one, when I brought it home and sat it down on the living room table for inspection, my wife looked it over from all angles, played a couple of trial games, then announced, "When I divorce you, I'm taking this one with me".

[badpenny]

............... Well, there's something to look forward to!
But don't worry about it, I can always get you a replacement Novamat.

[operator bell]

Well, I've had fun stripping my Novomat down and putting it back together, and learned a lot about it in the process. There are several German sites dedicated to these machines, which I laboriously read through with the aid of Google translations, but I have trouble finding anything a second time. The Germans take it really seriously, with info on how to re-cast broken parts on the garage workbench. I'm not quite that dedicated. Mine does have a broken payout slide, but I noticed that the slides are always held in compression, so if the broken slide is in the middle it can't separate and a little epoxy is all it needs to hold it together. If that doesn't work I'll cut a set out of 3mm brass sheet before I go to the trouble of setting up a foundry. Really good professional epoxy does a good job on the zinc cast parts. That's the slower-setting stuff that goes as hard as glass, not the consumer "5 minute" quick-set that never gets much harder than a fingernail.

I decided 45% payout was a bit ridiculous so (after double-checking my math) I modified it to bring it up around 90% payout - this involved surgery - and made a new set of reel strips using images I got from the German sites. I also modified it for US quarters, since these are just the right thickness - changing the coin thickness is a major, major job on these machines since the coin thickness is set by the mechanical leverage all the way back to the reels. NB, the Wulff is a "five-click" machine. There are two releases on the payout slides, first the payout setting rod (which must hang free and loose) and second the inner master release, which releases the assembly after the setting rod has been withdrawn the right amount. If you can't hear two clicks after the reels stop, it's not set up right.

There's no doubt that the outer case, if not the mechanism, started life intended for a much smaller coin than 10 pfennig. I would guess 20mm or smaller, as the coin head had a "second coin return" feature with 22mm clearance, later blocked off with what looks like a factory mod. I couldn't find any reference on the German sites to machines that took smaller coins - has anyone ever heard of it?