This post is mainly for fun
But the Old Dog did want to make some quick points
1) A turn table can be used as a minumum radius curve
2) A turn table can be used as a "T" junction
3) A turn table can be used as a "X" crossing
4) A turn table can be used as a ladder
These items can save a good deal of space when space is extremely limited
Have fun
Cox 47 wrote:Anybody remeber TV stations running teat patterns? Sure looks like one to me LOL??....Cox 47
You're right, it does look like a test pattern.
Dog,
You need a hobby.
Chip
Building the Rock Ridge Railroad with the slowest construction crew west of the Pecos.
exPalaceDog wrote: This post is mainly for fun
I agree. It's hilarious!
The following is based on the (set in stone) fact that my standard length through freight is a smidge short of eight feet from front coupler to markers. Not all of my trains are 2-car MU sets.
Minimum radius 2 feet, space required 27" by 27", versus turntable, space required 96+" by 96+".
T junction built with 24" radius curves and commercial #6 turnouts, 38" by 76".
A 90 degree crossing occupies an actual space 1 1/4" square. Even an acute angle crossing (#20 double slip switch) only needs a space 2 3/8" by 48"
by using a sector plate the length of the turntable you eliminate the ladder altogether. Space required 100" long, 4N inches wide where N is the number of tracks (practical limit is about 6,) all of which can have staged trains on them.
I make the dimensions of the Dog's Nightmare to be 32 feet square. In about 1/3 the space I am doing a LOT more. Of course, my only turntable is a JNR standard locomotive carrier 250mm long.
I actually have seen turntables used (full size prototype) just as the Dog describes. They were VERY narrow gauge, about 1 meter in diameter, and could accommodate one mine cart. Motive power was a grimy pair of 0-5-0s attached to a husky coal miner.
Chuck (modeling Central Japan in September, 1964)
The Old Dog must question some of tomikawaTT's numbers.
The turn table used above is the Atlas 9" turntable. It will fit in a one foot by one foot space. One could do a 90 degree turn on one foot wide shelves. A normal curve would need about two feet by two feet.
Clearly, trains would normally be limited to say one short car and a small 0-4-0T locomotive or maybe two small trolley cars. If one wants a lot of hassle, a train could be run with a locomotive on each end. The cars could then be handed off over the turn table one at a time.
And tomikawaTT is correct, this style of layout would be more suited to Gn18. See chart below
http://dawgstrainhouse.com/forum2/index.php?topic=47.0
loathar wrote:Looks like something hippies would have built on a drug trip.
Actually, it reminds me of something I saw on one of those ink-blot tests once.
Dog, I thought at first you had posted one of these..
May have to click on it to get it to work. The image is actually a still image with no moving parts, but stare at it a few seconds and it starts to move. I see about 15 turntables in it..
JaRRell
The Silverton Railroad used a turntable to shed elevation quickly, in place of a switchback, near Corkscrew Gulch.
The locomotives didn't track or pull well in reverse, so a normal switchback wouldn't have worked. There wasn't room for a wye or curve on the side of the mountain, so the last few hundred feet of the lower track, below the switchback, was given a slight downhill grade, then both tracks were brought together using a turnout. The upper track naturally sloped towards the turnout.
About two passenger car lengths beyond the turnout was a small hand powered turntable. The procedure used was to set the brakes on the cars, and uncouple the locomotive short of the turnout convergence, regardless of whether the train was headed up or down the mountain.
The locomotive would cross the turnout to the turntable, get spun around by hand, then exit the turntable and exit the turnout on the opposite leg from the parked train, headed in the opposite direction from which it entered.
Then the turnout was relined for the train cars, the brakes were released, and gravity drew the train across the turnout and in some cases, onto and beyond the turntable, far enough to clear the turnout.
Then the turnout was relined for the loco, which backed up, coupled to the train, and then puilled it clear. The locomotive was always driven in the normal direction, but the normally front facing passenger seats were pulled forwards half the time, and in reverse the other half.
A couple miles above and below this contraption there was room for wyes, at which point the mess could be rectified and the passengers returned to a normal, front facing ride.
I've thought about modelling this, and could probably fit it all in during phase three construction, but haven't figured out yet how to remotely lock and release the brakes so gravity could finish the operation only at the proper time.
jeffers_mz wrote: ...I've thought about modelling this, and could probably fit it all in during phase three construction, but haven't figured out yet how to remotely lock and release the brakes so gravity could finish the operation only at the proper time.
...I've thought about modelling this, and could probably fit it all in during phase three construction, but haven't figured out yet how to remotely lock and release the brakes so gravity could finish the operation only at the proper time.
Retractable axle-high pin(s) might do the trick. I say possibly 2 pins to avoid interference with coupler trip pins or air hoses by a single centered pin.
Sounds like quite the interesting operation. Question is whether it would get boring or not on a repetive basis. Boredom was allowed with the prototype. The good point is that unlike a switching puzzle arrangement, you could waive the rule about turning the locomotive anytime you wanted, so that the turntable would only actually be used when the rule was in force.
I've doing a more traditional use of a turntable as the completion of a run-around track on my TH&B version of the Gum Stump & Snowshoe. That way, I can have the 2 locmotive requirement to get a train set up by ruling the turntable is for turning locomotives only. Or I can make life simpler by using the turntable as a run-around to allow operations with just one locomotive.
just my thoughts
Fred W
Some interesting links on this subject
http://carendt.us/microplans/index.html
http://www.carendt.com/scrapbook/page45a/index.html
http://www.carendt.com/scrapbook/page52a/index.html
http://www.carendt.com/microplans/pages/a3/A3works.gif
http://www.carendt.com/microplans/pages/industrial/trams/Perkoplan.gif
http://www.carendt.com/microplans/pages/industrial/trams/R-Q.gif
http://www.carendt.com/microplans/pages/shelf/turntable/twinpeeks1.gif
http://www.carendt.com/microplans/pages/shelf/turntable/smithereens.jpg
fwright wrote: jeffers_mz wrote: ...I've thought about modelling this, and could probably fit it all in during phase three construction, but haven't figured out yet how to remotely lock and release the brakes so gravity could finish the operation only at the proper time.Retractable axle-high pin(s) might do the trick. I say possibly 2 pins to avoid interference with coupler trip pins or air hoses by a single centered pin.Sounds like quite the interesting operation. Question is whether it would get boring or not on a repetive basis. Boredom was allowed with the prototype. The good point is that unlike a switching puzzle arrangement, you could waive the rule about turning the locomotive anytime you wanted, so that the turntable would only actually be used when the rule was in force.I've doing a more traditional use of a turntable as the completion of a run-around track on my TH&B version of the Gum Stump & Snowshoe. That way, I can have the 2 locmotive requirement to get a train set up by ruling the turntable is for turning locomotives only. Or I can make life simpler by using the turntable as a run-around to allow operations with just one locomotive.just my thoughtsFred W
The railroad was sort of known for three engineering miracles, at least they seemed miraculous at the time.
One was the Muleshoe Bend at Chattanooga, basically a hairpin turn up a side gulch on a 5% grade that bought them some 500 feet of vertical gain in a quarter mile of linear distance.
One was the passenger station inside the Wye at Red Mountain Town.
The third was the Corkscrew Gulch turntable.
I think it would get pretty tedious running regular trains through there, but it would have both prototype value and a wow factor, the first time someone saw it anyway.
For those reasons, the current expansion project precludes it, unless I later want to rip out 6 staging tracks, or replace a 2x4 extension with at least a 4x4 extension, which I don't have room for.
If it went in, it would be a once in a while excursion up a long grade, and maybe happen as often as I run the Shay's, and for similar reasons. It also wouldn't have anywhere near the flexibility or utility of what you're doing being so far away from the mainline.
I hadn't thought of retractable pins, I will file that away for possible future use. The best I had come up with to date was steel plate car weights and an electromagnet "brake" under the track. I suspect that would take a lot of finagling, and trial and error, and still maybe not work without constant fiddling. Decoupling would have to work reliably too, with potentially disastrous results for failures. There's some pretty significant exposure on that face, it's really steep.
I like the pins idea though, thanks for the tip.
:-)