The San Francisco CalTrain Station yard has five (5!) double slips in the configuration you describe.
When I modeled it I used five (9°30') Walthers(/Shinohara) #6 double-slips (948-8814) and a 19° crossing.
<http://geowarblog.freesite.website/blog/the-new-improved-plan>
Lowest diagram, #6 Peco turnouts, #6 W/S crossover, 2" track centres. Easy peasey!
Bill
steemtraynOh, really?
Nice. I did not know that that one was there. It makes tons of sense with that particular track geometry, but apparently not so much with the one the OP wanted.
I suspect that that switch is seldom used to divert trains, but it could indeed do so.
ROAR
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Bill, thanks again, I appreciate all of your input.
Rich
Alton Junction
I think that will be fine with the lower configuration. The W/S crossover is at 2" centres. The W/S turnouts give about 2 1/2" centres but can probably be trimmed to 2". Peco 83 #6 turnouts give 2" centres as standard so that might be an option.
Thanks, Bill.
My initial inclination was to use four double slips, both to save space and to minimize S-curves.
But, my main concern was trying to fit the double slips in a way that maintains a 2 inch parallel centerline among the four mainline tracks.
Hi Rich
Double crossover over plus 4 single crossovers will be easier and cheaper. It will take a little more room.
Without trimming this will give you 66mm centres outer-inner and 51mm inner-inner.
Bill, when I drew that crude diagram, it was posted just to illustrate the relative position of the four double slips to the double crossover. I agree that the actual track configuration of the double crossover is different from that diagram in the sense that the double crossover is essentially four turnouts molded together.
I have all but abandoned that original approach in favor of a double crossover connected to four single crossovers instead of four double slips.
The OP's diagram doesn't make any sense as a crossover is not made the way shown in his diagram.
To do what he wants to do he could dismantle the crossover it to make a crossing plus 4 turnouts as Chuck suggests.
An alternative is to use 4 turnouts, 4 double slips and a crossing, For #6 turnouts he will need a 19 degree crossing. Atlas make one.
With W/S #6 turnouts and slips and an Atlas 19 degree crossing he will get 66mm centres between an outer track and the inner track and 89mm between the two inner tracks without trimming.
The turnout and possibly the crossing can be trimmed to get closer centres.
BroadwayLion NYCT, which has every good reason to use double crossovers and slip switches as per your suggestion, does not use them,...
NYCT, which has every good reason to use double crossovers and slip switches as per your suggestion, does not use them,...
Oh, really?
https://maps.google.com/?ll=40.588252,-73.974394&spn=0.000346,0.000474&t=h&z=21
Dave
Just be glad you don't have to press "2" for English.
http://www.youtube.com/watch?v=zQ_ALEdDUB8
http://www.youtube.com/watch?v=6hqFS1GZL4s
http://s73.photobucket.com/user/steemtrayn/media/MovingcoalontheDCM.mp4.html?sort=3&o=27
Double Slips are much more complicated and maintenance intensive (more moving parts). Real railroads avoid complex trackwork anywhere there is space for more simplified trackwork.
NYCT, which has every good reason to use double crossovers and slip switches as per your suggestion, does not use them, rather they allow trains to snake there way across regular switches. Admittedly these are not high speed movements, but there you have it.
You could print out the Peco turnout plans and check it. Low cost. SL-93 crossover, SL-90 double-slips, SL-95 and SL-96 medium. http://www.peco-uk.com/page.asp?id=tempc100
http://www.peco-uk.com/page.asp?id=tempc75
They appear to only offer them in code 75 and code 100.
Ive set it up in RR track v5.0 using the Peco Library. It works on the software. I know that the Medium switch does infact have a 12 degree frog and the crossover is 24 degrees. (each track +/- 12 off center) I have not worked with the doulble slips. My club president shot me down on changing out a crossover for a double slip (mainline on a modular layout).
Edit: According to the RR-track software the Double Crossover has a 12 Degree frog angle. This matches with the turnout frog angle, and the angle of the crossover (24 Degrees or +/- 12 off of centerline)
BMMECNYC It can be done with PECO turnouts. PECO double slips have a 12 degree frog angle. They also make a 24 degree crossover. My club built a double crossover with the 24 degree cross and peco medium turnouts. It would not be too far of a stretch to throw in 4 double slips.
It can be done with PECO turnouts. PECO double slips have a 12 degree frog angle. They also make a 24 degree crossover. My club built a double crossover with the 24 degree cross and peco medium turnouts. It would not be too far of a stretch to throw in 4 double slips.
Or would it?
The cost of purchasing 4 double slips plus the crossing is what holds me back.
Unless I could be sure, by hearing from someone who has done it, I worry that the angle of the double slip will prevent me from accomplishing parallel tracks.
It seems that the use of four double slips, one on the end of each leg of a double crossover might work, but I think that the best course of action is to forget the double slips and just use crossovers.
I do appreciate all of the input though.
Thanks everyone.
You're right, Dante...
A little digging came up with these frog angles:
#4 = 14° 15'
#6 = 9° 32'
#8 = 7° 9'
#10 = 5° 43'
Thanks, Ed
Ed,
That's the potential solution I described in my reply, but no, a 30°crossing will not work. I did not calculate it, but graphically, it appears to require a 15°± crossing. #8s would require an even shallower crossing.
Dante
Definitely will work the same manufacturer DS and crossing. The DS replace the conventional turnouts in the double crossover. Giving you an additional route at each DS. Using PECO would eliminate the potential throw bar interference.
Larry
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tomikawaTT The other side looks at my advancing stage of decreptitude and admits that I could drop dead before finishing...
In that case, maybe you could come up with a layaway plan.
You should do it Chuck. Rumour has it, that Rich is Rich! Beyond the dreams of Avarice RICH!
You could charge him enough to build a third stall on your garage.
Brent
"All of the world's problems are the result of the difference between how we think and how the world works."
richhotrain Chuck, thanks, that is a bit of encouraging news. The prospect of building a handlaid track configuration such as this could well be the answer. But as a first time effort, that may exceed my current talents. Maybe I could cut a deal with you to build it for me. Rich
Chuck, thanks, that is a bit of encouraging news. The prospect of building a handlaid track configuration such as this could well be the answer. But as a first time effort, that may exceed my current talents.
Maybe I could cut a deal with you to build it for me.
Rich, one side of me says thanks for the compliment. The other side looks at my advancing stage of decreptitude and admits that I could drop dead before finishing...
Aging is a (female dog)!
Chuck (Modeling - mostly operating - Central Japan in September, 1964)
Hi, Rich
I have the geometry you are looking for except it's in O scale and it is hanging on my train room wall! I had saved this from a layout in my cloudy past and it was too beautiful to toss! In this example you can see that you can go from track -1 to -4 in a straight line with no S curves which is one of your goals.
Actually what you are looking for would not involve a double crossover at all as Brad states above. You would need 2 left and 2 right turnouts; four double slip switches and only ONE crossing. (does 30° match a #6 frog? I forget.) You would probably want to do this using at least #8s.
The trick would be trimming the rail ends of the double slips in order to get the track centers you want and fitting the crossing into the middle of the whole mess will be a bit of a challenge.
Below, you see that I had to trim these double slips on my Union Station throat in order to achieve 2.125" track centers.
Not exactly what you are looking for but I show it here just for an idea. Here's a link to the printable Walthers track templates. Cut and Paste Away
https://www.walthers.com/exec/page/track_plan_code_83
Have fun, ED
nedthomas The Walthers reference book has templates (page 229 of the 2014 book) you can photo copy and use for track planning.
The Walthers reference book has templates (page 229 of the 2014 book) you can photo copy and use for track planning.
Assuming that you have the 2014 reference book.
Incidentally, my plan would be to use Tortoises in this portion of the layout.
Howdy, Rich,
What you have drawn can be built with Walthers/Shinohara parts, with the following caveats:
OTOH, hand-laid, no sweat. Built one like that for a club 40 years ago.
Chuck (Modeling Central Japan in September, 1964)
Geometry aside, the double slips are rendered pointless by the four turnouts of the double crossover. To make your idea work, you'll need to scrap the double crossover and simply use a crossing, *OR* scrap the double slips and use conventional crossovers instead. If space is tight, I think you'll be well served with the 4 double slips and single crossing (as well as saving the rather substantial cost of a double crossover).
I am debating a similar arrangement on my staging yard, whether to use standard crossovers, or a single slip (I would never need one of the diverging routes of a double slip).
Brad
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Thanks, Dante, you confirmed my worst fears. When you look at the angle of the double slip, it doesn't look like it will fit the way I want it to and that is why I asked. I think what I will do when the time comes is to simply add crossovers at each of the four ends of the double crossover and be done with it.
I haven't attempted this in reality, but I do have a Walthers #6 DS installed and a #6 double crossover off the layout. Also, I have these elements in my model rr cad program. It is not possible to arrange the elements as you have shown them because they cannot connect that way. If you use 4-#6 DS only, shorten them by about 2" each where they "join" and fabricate your own custom crossover (about 15°?), it might work. The throw bars on the DS's will likely have to be cut short, also.
Instead of making a custom crossover element, perhaps you could "dismember" the double crossover: use its crossover element to join the DS's and use its #6 turnouts as the leads from the mains to the DS's.