Wednesday, July 4, 2012

PoNY Marine Shops propose working car float operation

Some doodles came in from the PoNY Marine Shops just before bed last night.

Something I hinted at a few posts ago was the desire to have an operating car float service for the PoNY, and late last night I received some initial sketches from the PoNY Marine Shops.

Much of the "staging" is going to happen via car float service since most of the layout will be comprised of isolated pocket yards. To get traffic to and from the different parts of the layout, it will be necessary to move car floats around just like the prototype situation in the harbor.

This may be a wild hare, but wouldn't it be fun to pilot those car floats to and from the different destinations?

The idea is pretty simple, but the execution may be a bit tricky. Calling on some experience in radio control cars, I bet I could get a pilotable car float and tug boat service working for about $600. Using the chassis from an R/C truck with modified suspension (a lot stiffer for the increased load) as the basis for a lightweight aluminum cart with a tug boat mounted on top of one and car floats mounted on others. The idea is to be able to steer the tug boat cart to the car floats, have it lock in place and push/pull the car float carts around to the different pocket terminals of the PoNY.

The tricks will be in the wheels of the car float carts that should function as omni-directional as possible to simulate being on the water. The tug boat cart will steer like a truck, which I think is fine. Docking will also be interesting, and some sort of mechanical capture system like a hitch assembly with an adjustable connection at the float bridge/car float possibly using magnets to hold things tightly while working the float. These could have power feeds attached in order to allow locomotives onto the floats (which did happen). Install a Dallee or similar tug boat sound system that is tied into the R/C, and viola! an operating car float service.

Lateral stability will be an issue when the tug and car float carts are separated, but when they are together, they will have a wide stance. Weight may be an issue for the R/C power system, but that should just be a matter of finding a hefty large scale motor and chassis assembly. I'm not too worried about this aspect, as the aluminum construction will make for a stiff, yet very light load for the drive system. Another potential sticking point is the car float wheels. It would be ideal to have large casters or wheels that are independent and easy to change directions with.Conceptually, large ball bearings that have totally free 360 degree movement would be best. This may take some searching for anything with these qualities.

So that seems easy enough, eh? I'll keep doodling and get some input from you all and my go-to engineering buddies here in town. I'm thinking I should build at least one other pocket terminal before tackling this so that it has someplace to go. I just have to decide which one as I am ready to try a Gatorboard and aluminum baseboard structure for easy deployment/removal and possible transport of the next yard around the house and to shows. Stay tuned for updates as this project develops.


  1. Great ideas to "float" car barges to and fro.
    I saw some where on this site that you were considering modeling a portion of the Jay St. Connecting?

    1. Jay Street is on the list, yes. I'm thinking that I can build a bunch of these terminals and then selectively set up different ones for different operating sessions. The idea is to capture some sense of all of these small terminals as independent parts of a large overall collection that made up the enormous New York harbor railroading environment.

  2. Riley -

    I have a similar "contraption" on my layout, though it is not motorized....Not sure if I have a pic on my blog of it, but I do have a couple to send you if you are interested in seeing. I'll admit, it's all very crudely constructed at this point, but it does work. We will be refining it to be trouble-free later this summer during the upcoming shakedown sessions. So far, it didn't case derailments (much) and is not electrically connected to the rest of the layout (something it should probably be), but it does have working toggle bars!

    My manual "float cart" was constructed not to allow "floating" of cars between terminals (I don't have the room!), but rather to allow access to the back two floats for loading/unloading (fiddle style). The reach over would have been too much even for a tall person like me, so I needed a moveable solution to my carfloat access woes, and it came in the form of a metal library cart. I would have built my own had I not had one dropped in my lap, and the added bonus is that it has shelves for storage!

    I really like your idea, and hope it works out.....No reason why we shouldn't add more "play value" to an already neat operation.

    Ralph Heiss

  3. I have a similar set of doodles in my Harlem Transfer layout folder, though I hadn't gone so far as to consider r/c tugs!

    The main issue I came up with with that of stability. As my HT will be an exhibition layout, the long (36"), narrow (9") and high (48", to match the layout's height) give me concerns about tettering over and dumping a few hundred quid's worth of freight cars to the floor. So maybe a 36" square base, tapering inwards to match the carfloat's beam. Even though that would possibly make it more awkward to operate.

    I'd also looked at ways of having the carfloat pivot centrally along it's longitudional axis , so it lists prototypically as it's loaded/unloaded (and thereby forcing the use ofprototypical loading methods!) The key there is some form of damping (soft foam blocks, possibly) so that it (again) doesn't dump those repaired freight cars back on the floor!

    For your tug, would you set the chassis up to steer from the rear, to better replicate how a boat turns??

    London, UK

  4. All excellent considerations, indeed.

    I think that having large-diameter wheels is key. the best thing would be to have as large a base as possible, but as you say, maneuvering becomes difficult in proportion to the width of the stance. I was thinking, but didn't include in the sketches, that there would be ballast at the bottom to stabilize the cart. There may well end up needing to be some sort of car-locking device. Or, have a wide patch of ocean on either side that travels with the float and tug.

    Your center pivot seems even more sadistic than my tug. :) A small electronics package could probably sense then actively move a car float to simulate what you are talking about. Along those lines, a working float bridge would be fun as well. I think there are examples out there.

    I really like your suggestion of setting up the steering from the rear!

    Do you have