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Replicating tight prototype curves in HO

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  • Member since
    September 2014
  • From: 10,430’ (3,179 m)
  • 1,229 posts
Posted by jjdamnit on Thursday, February 13, 2020 1:34 PM

Hello All,

PECO makes #2 HO turnouts- -both right and left.

On my pike I have incorporated several of these tight turnouts.

I used and opposing pair; one right and one left, to make a short coal loading siding.

Another pair, along with an Atlas Mark IV wye Turnout, makeup the wye to turn the steam locos for the excursion train.

With these you could add flex track to tighten the radius.

In certain urban areas, where tight turnouts were necessary, a single-point turnout was used.

There was an article in either The NMRA Magazine or in MR Magazine about hand laying one of these.

I did a search of the web and came up with several examples of these types of single-point turnouts.

Hope this helps.

"Uhh...I didn’t know it was 'impossible' I just made it work...sorry"

  • Member since
    February 2002
  • From: Reading, PA
  • 28,014 posts
Posted by rrinker on Thursday, February 13, 2020 1:13 PM

 The turnout in the foreground is a standard one - streetcar turnouts usually only have one point. It may be a wye - a #4 wye has each branch going off the center line at the equivalent of a #2. So even a #6 wye diverges sharper than a #4 standard left or right turnout, yet the frog angle is a generous #6.

 I doubt the curves are much tighter than 15" radius in HO - even a 40" radius in HO is a reduced speed curve for the prototype. But you can bend flex track down below that - I had some bent down to about 3 or 4" radius before it kinked, a little 4 wheel trolley ran over it fine. At slow speed.

 There was a picture which may have mentioned the prototype radius, of one of the piers on Delaware Ave, mainly showing off the primary home of Reading's SW1's - which had modified draft gear to get enough couple swing to push and pull cars around the curves. 


Modeling the Reading Railroad in the 1950's


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  • Member since
    July 2012
  • From: Philadelphia, PA
  • 12 posts
Replicating tight prototype curves in HO
Posted by RedImperator on Thursday, February 13, 2020 12:30 PM

Hi everyone,

I'm working on track planning for an HO-scale industrial switching layout based on the PRR Washington Avenue branch, in South Philadelphia. The branch ran west to east between the Schyulkill and Delaware rivers, mostly right down the middle of Washington Avenue, serving factories and coal/lumber/ice yards along the route.

I want the centerpiece of the layout to be the area along the north side of Broad and Washington (see attached Bromley Atlas 1910 picture for an overview), with two freight houses, a vest-pocket yard, and a factory that produced clothing for John Wanamaker's department store. My issue is the turnout and the curve to get from the WB main line into the Wannamaker loading dock (circled in red on the map). It's much tighter than 15" in HO as near as I can tell, and the turnout seems sharper than anything I've seen for sale from the usual suspects (Atlas, Walthers, PECO) in Code 83. I know these old atlases and fire maps aren't 100% accurate for representing railroads, but I know the area and I've seen enough pictures of the factory building to trust that the map is basically accurate in this case (I couldn't find a picture of that exact junction but I've attached one from a block or so further down Washington, showing a switch connecting a storage building to the branch line; you can see it's more like a streetcar turnout than something you'd find on a normal freight railroad). 

My question is, short of hand-laying the turnout, what might be available to replicate ultra-sharp diverging tracks like that? I'm not too worried about rolling stock--everything will be pre-war freight cars and I'm happy to use a handle for setouts and pickups if an 0-6-0 can't navigate the turn directly--but I'm having a hard time finding a switch that will work. Is it really just a matter of using an Atlas #4 and bending the flextrack to something insane like a 6" curve, or is there a better option available?

 PRR Washington Avenue Branch, 1910

Tracks at 12th and Washington

Any city gets what it admires, will pay for, and, ultimately, deserves.

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