Has anyone ever attempted a working ball signal??

[randgust]

Not a joke.   One of the oddest things that have shown up in photos of the Hickory Valley / PRR diamond at West Hickory is clearly the mast of a classic ball signal.   And I've modelled that diamond years ago.

So you have two balls, unlit, separate, on two pulleys top and bottom.    Forget trying to make the loops and pulleys move, I think it would be possible to use them simply as guides, and do a wire pushrod from the bottom on both to move the balls up and down; more or less like the control of a crossing gate from underneath on a Tortoise machine.

The big difference is the vertical movement travel, it's probably more like an inch and a half so the actuation arm and the pivot will take some engineering.  And 'one ball up = one ball down' is a challenge.

Before I mess with this on my Ttrak module I'm wondering if it's ever been done by the likes of DKS, the animation master, or somebody else, or a better approach for a mechanism.   I'd do the mast and most of this in brass, soldered, as it's on a module.   I have watch gears for the pulleys.

This is 'close enough' to what I can identify on the old West Hickory diamond photo:
https://railroadsignals.us/early/ball/index.htm

What also stuns me is that was a PRR main line of sorts being protected, and PRR in that era was semaphore happy.  And the only 'human' there was the toll collector for the private road/railroad bridge, likely the person responsible for setting the 'lowball' on the PRR when the Hickory Valley movement was crossing.   I'd love to find a circa-1920 employee timetable or rulebook to find out how that worked but that won't happen.   My great uncle was the tolltender there.  Interestingly the 1917 HVRR val map shows NOTHING, maybe the PRR map did.   But the diamond photo is new enough that you can clearly see a Model T in it, so that's the era.  In that time period PRR was taking control of the WNYP, so PRR standards in signals were late in coming, that's all I can think.  The junction north (at Irvineton) was laced with semaphores on the Erie, PA to Renovo main line.  https://www.west2k.com/papix/irvinepa.jpg     So a ball signal on the same line south kinda messes with my head.

Those of you that have seen all the working vintage pushrod oil wells on my Jamison T-trak module know how much of an animation/gearbox nightmare that thing is, this is easy in comparison.

[N Scale Train Boy]

Never heard of this being done, but would love to see it happen, because that would be AWESOME! Like the functional MSS controlled semaphore that I saw on the FreeMoN layout at Springfield this past January, I am fascinated at seeing these older signaling systems brought to life!

[delamaize]

Hmmm... I'd be willing to bet something could be done with a pair of servos, pullies, some nice monofilament, and an Adriano mini computer. It's over my head programming wise, but I can see the mechanical aspect of it in my head.

I don't know if DKS ever comes around anymore, But, I'd love to hear his ideas on this.

[randgust]

One 'DUH!' feature I just realized is that because this is on a Ttrak module, not a layout, I'd have the same power supply problems I have on Jamison module with the oil wells. Tracks have a wiring standard but you're kinda on your own for accessories power.  That module has two battery power supplies, one rechargeable lithium battery pack for the Arduino MPG sound generator, and another 4-pack of AA batteries just to power the motor gearbox for the oil wells.  Oh, and an external plug for a power pack if I do somehow have access to 110V, with a voltage converter for both.  Keeping that thing running, alive and power functional at shows is proven 'out of proportion' maintenance heavy.   

So maybe some simple levers, or cranks, or something manual is more to order in this case......  it's right on the front edge so a heavy motor drive seems like overkill.  I'm more concerned about the fragility even in brass.

I've been wondering for years how that HVRR diamond must have been controlled, you just don't run across a PRR main line with smoke signals.  But I never expected a ball signal, certainly not here.

[Chris333]

The Maine two footers used ball signals and I've seen them powered before. (In larger scales)

[Maletrain]

Not understanding why you rule our making the pulley's work.

I am no expert, but my thoughts run towards making the balls go up with string winding around a drum and having them come down with spring force.  Heavy balls would be a problem with moving the modules, so very light balls on tense strings seem like the solution.

Why not have a motorized drum under the module surface with the string going up the center mast, out the arm, around a pulley and down in the open with a ball attached, then up to the arm and then back inside the arm to the center mast, down the mast to a coil spring under the module surface that gets stretched by the motor pulling on the string?  One such setup for each ball.

That allows the tension on the string(s) to be controlled by the strength of the spring(s), rather than the weight of the ball(s).

There would need to be some sort of limiting device for how far the powered drum(s) turn.  Given the thickness of the T-Trak module base, a drum could turn substantially less than 1 full turn to move the ball the required vertical distance.  So, contacts on the drum could be used to make and break the circuits powering the drum in an appropriate manner.

Assuming you want to lower and raise the balls automatically with train passage, it seems that some sort of sensing mechanism for track occupancy would be needed.  There are a lot of those of different sorts available.  If somebody has already figured out how to use the output from one of them to control servos for semaphores, then it should not be hard to figure out how to control the drum winding and unwinding the string in the ball raising mechanism.

BTW, I go past the High Ball preserved in Delmar every Wednesday.  So, if you want some pictures or measurements from that, let me know.

[Chris333]

[garethashenden]

And 'one ball up = one ball down' is a challenge.

I do not believe this to be true. Or at least it is not always the rule. One ball down, then one ball up is closer to the rule. You remove permission before granting it to the other route. Two balls down should be a valid position.

Edit: From my copy of a 1931 Boston & Maine rulebook, there are three rules covering the use of ball signals. The most relevant is 695:
"When the movement of trains and engines is governed by ball signals or lights at mast-head, the men in charge will not raise the ball signals until three minutes before regular trains are due; and as soon as the train arrives or passes will immediately lower all signals." All three rules remain unchanged in the 1961 rulebook.

So really you need two fairly simple mechanisms. A ball on a string with a motor under the ground. It gets pulled up, it gets pulled down. Have two of them side by side and set up the controls in a way that reminds you not to have both balls up at once.

[randgust]

I've been looking for a set of drawings unsuccessfully (help more than welcome!!), but the apparent diameter and size of actual pulleys (spoked, as well) is daunting.  Appear to be about 12-18".   If the pulley system is static, one side is just a vertical guide, and then a vertical wire (say, .005-008) as a pushrod on the signal ball up and down, coming up from the bottom, gets around the maintenance nightmare and fragility of actual strung wires and moving pulleys.

If there's one thing I learned about wire-driven animation in the T-trak Jamison module, it's that in a public show, it's gonna get whacked and needs to be adjusted.  I made all those connections breakaway hooks on .010 wire, and I'm glad.  The vertical well rods pull out, are adjustable, and have tiny alligator clips on them to adjust vertical travel under the roadbed.   This signal will be right on the front edge, very noticable, but very exposed as well.  So brass, probably removable.   I've had those wires hit in EVERY show, even with a warning sign.   It's not the public either...

The 'gas engine' in Jamison, with the working drive belt, has proven to be the most failure-prone piece of the animation mechanism, and it's 10X the diameter of those signal pulleys.  Requires constant adjustment and tinkering.   

That On30 ball signal is way cool.  And good tip on signal rules that 'both down' is a valid aspect display.

My DKS salute to N animation on my Jamison module: 

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[garethashenden]

Can you put a piece of plexiglass in front of the signal to protect it?

[Maletrain]

First, I think that trying to make the visible pulley wheels both operate and have scale appearance is not likely to be workable.  In my previous suggestion about using pulleys, I was thinking of scale-looking pulleys for "show" and smaller, tiny pulleys for the threads to be guided by at the 90 degree bend points to go into the horizontal arm and then down the vertical mast.  Obviously, macro photography would show that it is not exactly the same as the prototype.

If you want to use the "rope" attached to the ball as a vertical guide for "rods" (tubes) that push the balls up from the bottom, you will also have some obviously non-prototypical connections, but at the bottom instead of the top, and probably more noticeable.  The "rods" could be stainless steel tube material used for medical syringe needles, sliding over 0.006" stainless wire.  But, the noticeable thing would be the difference in "rope" diameters above and below the balls.  I think you could blacken the stainless material so that it would not need to be painted.

I'll second the motion to put a plexiglass barrier at the front of this module.  But, as it must be close to the track, people running trains will need to be able to reach over it to deal with potential derails.  So, good trackwork is also probably a necessity at this point.  If there is an associated turnout in the vicinity, that seems like a likely cause for hands going near the ball signal.