I have a plan for a project with my grandson that is a pared down HO take-off of MR's old Blue Coal and Stafford Town RR (it can be googled). If I go with the three loops it will still require a single crossing, and a rather narrow one at that. A rather quick check on the 'net seems to indicate that Atlas may make the only ones narrower that 30 degrees, selling 19 and 12.5 degree assemblies. I do not wish to ugrade the junction by replacing it with a slip switch.
It would seem logical that the narrower the intersection the more probable are derailment issues, especially with finicky pilot or trailing trucks and lighter rolling stock. And all the more so with the crossing's proximity to any curve, however slight. Is my concern unreasonable?
BTW, DC and NS code 83 on a 5' or 5.5' x 10' (for now I'm disregarding the end extensions on the original plan). Going to see if I can do it with minimum 21 or 22 inch curves and #6s on the main (for steam I have an old MDC Prairie and a Genesis Mountain that I'd like to run on it). Wish me luck with drawing it up this weekend.
Thanks in advance.
John
Nope, the angle of the crossover won't affect anything whether it is 90 or 12.5 it will be the same as it is basicly the same as taking the straight route on a switch just with a few more frogs to cross so which ever fits the plan best should be fine.
A bit of a tangent, but I have three Atlas 2012 vintage code 83 NS 90 degree crossings that had a (fixable) problem. It took some filing as either the wheel flange depth allowance was too shallow or the guard rails were too tight to the rails. I forget which or both issues, but some filing took care of it. Might have just been the run I got.
I'd check with a NMRA guage before installing.
Paul
Modeling HO with a transition era UP bent
Are derailments a problem on these types of crossovers?
For most of us out here,
This is a "crossover":
This is a "crossing":
So when I read the topic name (Issues With Narrower Crossovers?), I expect to read about concerns that the two parallel tracks are too close together.
Ed
My bad, Ed. I shall update myself to "crossings". But wait, even that's too comprehensive as it brings to mind gates and flashers, etc.
Cool Hand Luke strikes again: "What we have here is a failure to communicate."! Could be worse, though. I could be trying to have a conversation about the finer points of DCC programming.
ANd I'm surprised that the top one is marked for 30, even if that's kph instead of mph, unless it's a trick of the camera and it's not a sharp an S curve as it looks.
A shallower angle CROSSING just means the frog area is larger, the only possible issue is short pickup wheelbase locos may stall so it may be wise to look for one that has metal frogs that can be powered. 9.5 degrees seems to be about as shallow as they come (Peco has one).
As far as CROSSOVERS - you either want them to be as long as possible, or as short as possible, to minimize the S curve effect. You can make them longer without changing the track spacing by using larger higher frog number - shallower angle) turnouts. Or increase the track spacing with otherwise the same size turnout. Likewise they can be made shorter using smaller (sharper angle) turnouts, but if your locos or rolling stock can't negotiate a #4 turnout, they definitely will not negotiate a crossover made with #4s.
--Randy
Modeling the Reading Railroad in the 1950's
Visit my web site at www.readingeastpenn.com for construction updates, DCC Info, and more.
Attuvian My bad, Ed. I shall update myself to "crossings". But wait, even that's too comprehensive as it brings to mind gates and flashers, etc.
Good point. But that thing with the gates that MOST people stop short of is called a "grade crossing". The all-rail one is probably more correctly called a "crossing at grade". See. TOTALLY different!
Cool Hand Luke strikes again: "What we have here is a failure to communicate."! Could be worse, though. I could be trying to have a conversation about the finer points of DCC programming. John
Well, if it's with me, it certainly WOULD be worse.
Your issues will be no different with a 12.5 degree crossing than with a #4 or #5 turnout. (Frog angle is similar) You will actually likely have more issues with #8 or larger turnouts (#10, #12 etc), as the frog angle narrows, it becomes more likely that an out of guage wheel or warped truck will pick the frog point.
Had a recent run SD40-2 from Intermountain that liked to pick #6 Peco Code 83 frogs. I placed it on a flat surface and found both trucks were warped. I sent it back (for cost of postage) and they fixed it for free.
Use a NMRA guage to check the wheel guage, and you will have fewer problems.
Attuvian A rather quick check on the 'net seems to indicate that Atlas may make the only ones narrower that 30 degrees, selling 19 and 12.5 degree assemblies. I do not wish to ugrade the junction by replacing it with a slip switch.
PECO makes a Code 100 12 degree crossing and a 24 degree crossing.
https://www.walthers.com/code-100-streamline-crossing-short-insulfrog-24-degree-18-quot-45-7cm
I dont know why they say the 24 degree is 18" Nothing on that piece of trackwork is 18". http://www.peco-uk.com/imageselector/Files/Track-templates/SL-93.pdf
https://www.walthers.com/code-100-streamline-crossing-long-insulfrog-12-degree
http://www.peco-uk.com/imageselector/Files/Track-templates/SL-94.pdf
And apparently a 22.5 degree one I was unaware of:
https://www.walthers.com/crossing-code-100-medium-22-1-2-degree
Here's the 9.5 degree one
http://www.peco-uk.com/product.asp?strParents=3309,3322&CAT_ID=3327&P_ID=17388
Go directly to Peco, Walthers is wrong. The 24 degree one, Peco calls a "short crossing" and lists it as 5".