Just for grins, here is a challenge. The Pennsy had its famous Horseshoe Curve, and the D&RGW had its Big Ten curves west of Denver in the foothills of the Rockies. Here are my nominations for the Frisco Horsehoe Curve and for the Frisco Big Ten Curves. Question one, where are they? Question two, anybody have others? The curve deltas must be within +/- 20 degrees of 180 degrees, and the degree of curvature must be greater than 8 degrees. And lastly, does anybody have any pictures at these locations?
For those of us who are severely challenged by math, roughly what size are we talking about? 1/8th a mile across, 1/2 a mile across?? Thanks, John
I Like it Karl, I have managed to model this pretty darned close to what your second image shows, and I didn't know it, not a clue. Now I can say there is a little of the Frisco modeled on my RR. I will be interested where this is and the grades involved. Tom H
I thought that you might get that one.... from railroad north to south first curve is 8 deg-04 min, delta = 151 deg-24 min, elev 5"; second curve is 8 deg-09 min, delta 100 deg- 15 min, elev 5"; third curve is 8 deg-02 min, delta = 187 deg-14 min, elev 5". The grade through here was increasing southward and ranged from 0.38% - 0.80%. The 1971 System ETT had a 25 mph limit through here. Technically, it's not a Big Ten curve, but perhaps a Big Eight curve will suffice. It's still an interesting alignment. Although it's not on the Frisco, Monroeville is the closest town to this location.
Karl, Thanks for posting. I do not want to take the wind out of folks sails yet as they search for the the location of the first image. I have been curious for some time to know if this is the sharpest curve on the Frisco's main lines. I have long admired the curve, but have not yet seen photographs of trains at the location. From the maps it does not look to be easily accessible. It would be fun to hike into the site to take a look at this time of year before it greens up again. Hopefully others will enjoy also finding the location. Hope this helps. Thanks! Mark
Karl, I found the location in about 3 minutes, using the clues that you have dropped on this web site so many times. I too, will not spoil the fun for others.
As might be inferred from Keith's comments, the curve lies on my favorite Clinton Subdivision at MP D129+13 poles to D130+4 poles. The location is roughly one and one half miles north of Weaubleau. Mark, Keith, and Dale picked the location; Dale is incorporating the location into his N-Scale Clinton Sub. Mark opined that this may be the sharpest "mainline" curve on the Frisco; I have long held this opinion, but I can't prove it, since I lack a track chart through this area. I tried to photoshop Dale's Clinton Sub profile in order to obtain an "official" max curve value, but I could not clean up the drawing sufficently to do so. Google Earth's "Ruler" utility places the radius at about 550 feet, which calculates to about a 10.3 degree curve. The grade is 1.4% as the Highline climbs from the Osage River watershed to the Springfield Plateau. I would have loved to have been on site, back in the day, when the 1632 had train 55 in tow. I'll wager that one could hear the stack talk and the squeal of the flanges in town. The questions still remain; does anyone have pictures from these two locations? Does anyone have other nominations? BTW, Peggy's is a cafe in Collins. They used to serve really good pie.
I wish I would have seen this thread a week ago. I should have recognized those curves in a heartbeat as much time as I've spent working on them so far. (see attached pics) My grade ended up being 1.38 % at the sharpest point in the curve so looks like I was pretty close. Peggy's did have good pies but you can't beat Smith's pork tenderloin...
Awesome stuff. Looking forward to running a vscale train on this someday! I also have envisioned something similar at the end of a peninsula of my new n scale layout. As tight as this was in real life at 550' radius it still works out to 41.25" radius in N scale so my horseshoe curve will be much tighter, more like 12" radius. Dale Rush Carthage, MO
Thanks, I am working on cleaning up the new plans that include the second level and will get them posted once I do. The old plans do not include the horseshoe curve. The new layout with second level added a couple of towns (Weaubleau, Walnut Grove) and gives more distance between towns for scenic features like the horseshoe curve, tall wood trestles in the Gerster area and the Sac River bridge. Dale Rush Carthage, MO