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Discussion Boards => Large => Topic started by: mudhen on June 03, 2013, 05:49:22 PM

Title: D&RGW .......real track sizes.
Post by: mudhen on June 03, 2013, 05:49:22 PM
Does any one have any idea what the real track turning radius on the D&RGW or D&RGS would have been to accommodate the K-27's,28's,36's and 37's.???????
I know some engines had center drivers with no flanges or so called blind drivers, to help on sharp curves and switches like the C-19's
Also the size of smallest to largest switches too ??????? and what where the maximum grades they encountered???????
I have heard so may different answers, I thought it would be interesting to here and confirm what I have heard to be the truth.
Thanks in advance for all replies and I will reply latter with what I think are the correct answers.
Title: Re: D&RGW .......real track sizes.
Post by: Chuck N on June 03, 2013, 06:55:04 PM
You are asking very complex and difficult questions.  The only way to know for sure is to do your own research on the entire trackage of the RRs of interest.  A place to start would be the Colorado Railroad Museum in Golden, Colorado. They might have maps and surveyors measurements.  No matter who says what, there are probably exceptions somewhere alone the routes.  You didn't ask for generalizations, but facts.  Chuck
Title: Re: D&RGW .......real track sizes.
Post by: Kevin Strong on June 03, 2013, 10:26:12 PM
I can't speak to minimums, but the reverse loop at Antonito is 232' radius, which translates to a 25-degree curve. (There's one at Osier--according to Google Earth--that's nearly the same diameter.) The Ks routinely run these loops, since they're built specifically to turn the locos.

Here's a link for specifics on the switches:

http://www.railroad-online.de/drgwtracks.html (http://www.railroad-online.de/drgwtracks.html)

This site talks about #8.5 switches, which I would presume to be the minimum. (The switches on the EBT are right around #8 switches, so I'd accept that as typical.)

Grades? According to the track profile maps in John Norwood's Rio Grande Narrow Guage, the maximum grade was 4%, and that was on the line between Chama and Cumbres. Most other places were less--around 2.5% or so.

Later,

K

Title: Re: D&RGW .......real track sizes.
Post by: mudhen on June 04, 2013, 04:56:48 PM
Kevin.....
What would they be in G-scale... Just a best guess is what I am after.
I'm thinking 20' Dia. track would and works best for me, and as yet I don't use switches, but think bigger is better.  
Title: Re: D&RGW .......real track sizes.
Post by: JerryB on June 04, 2013, 06:40:10 PM
Quote from: mudhen on June 04, 2013, 04:56:48 PM
What would they be in G-scale... Just a best guess is what I am after.  

No guessing required. Just divide the prototype dimension by the scale.

232' is 11' 5" in F-Scale (1:20.3). Note that is radius! The diameter is twice that or 22' 10".

Also note that Kevin gave the radius for a turning track. I'm not an expert on Colorado narrow gauge operations, but most RRs run their locomotives very slowly on small radius tracks such as those in yards and on reversing loops. Much less chance of putting a locomotive on the ground.

The mainline probably uses somewhat larger curvatures.

As to the switches, a #8.5 switch is a #8.5 switch regardless of the scale.

Happy RRing,

Jerry
Title: Re: D&RGW .......real track sizes.
Post by: Chuck N on June 04, 2013, 07:29:27 PM
Well stated Jerry.  I was about to mention the simple math needed from Kevin's post.  You beat me to it.

Chuck
Title: Re: D&RGW .......real track sizes.
Post by: Kevin Strong on June 05, 2013, 10:56:40 AM
Measuring from Google Earth, the easy-to-measure loops on the C&TS mainline come in at around 580 diameter (290' radius) minimum which equates to 20 degrees. In 1:20, that's 14' radius (28' diameter) curve.

By comparison, the loops on the Georgetown Loop RR come in at around 375' to 400' diameter. That was C&S territory, which used smaller locos than the D&RGW's Ks. In 1:20.3, that would translate to 9' - 10' radius (18' - 20' diameter).

Random trivia: The tightest 3' gauge curves in the US are believed to be the 60-degree curves on the Uintah RR - about a 5' radius. Those were the domain of the Shays and 6-coupled locos. To my understanding, nothing with 8 drivers could make it around that curve. (Hence the articulateds being 2-6-6-2s)

Later,

K
Title: Re: D&RGW .......real track sizes.
Post by: GG1onFordsDTandI on June 07, 2013, 05:58:13 PM
Quote from: Kevin Strong on June 05, 2013, 10:56:40 AM
Measuring from Google Earth, the easy-to-measure loops on the C&TS mainline come in at around 580 diameter (290' radius) minimum which equates to 20 degrees. In 1:20, that's 14' radius (28' diameter) curve.

By comparison, the loops on the Georgetown Loop RR come in at around 375' to 400' diameter. That was C&S territory, which used smaller locos than the D&RGW's Ks. In 1:20.3, that would translate to 9' - 10' radius (18' - 20' diameter).

Random trivia: The tightest 3' gauge curves in the US are believed to be the 60-degree curves on the Uintah RR - about a 5' radius. Those were the domain of the Shays and 6-coupled locos. To my understanding, nothing with 8 drivers could make it around that curve. (Hence the articulateds being 2-6-6-2s)

Later,

K

Nice info, love the Google idea.
Title: Re: D&RGW .......real track sizes.
Post by: Chuck N on June 10, 2013, 09:59:46 PM
K:

Using your idea which was great, Google Earth. I measured the return loop in the Durango yard for comparison to Antonito.  I get a radius of 225' ( a diameter of 450').  Which is a little smaller than the one at Antonito.  My measurements at Antonito give a radius of 235', versus your 232'.  A difference not worth worrying about. 

This works out to about 11' radius in 1:20.3 for The Durango loop.  I haven't been in Durango for a long time.  Do they turn the Ks on the loop or use the turn table?

All this says, is that if you want to be prototypical in your layout you shouldn't have any curves less than 11' radius.  Other possible places to measure might be the wyes at Silverton, Chama and if there is anything left in the areal images of the wye at Cumbres. 

Chuck