Have spot in my layout where a curved turnout would be needed. Any issues with curved turnouts - more prone to problems / derailments? (would be a RH #4 Code 83 - BK Enterprises)
Thanks all!
I’ve got several Peco curved turnouts. They are no problem at all. I use the Peco switch machines on them, and the only time there’s a problem is when I forget to throw the switch. (D’oh!)
There is, of course, a bit of a catch. A turnout on a curve is probably going to be joined to curved flex track on all 3 ends, right? Take great care to get the rail joints right. I’d suggest soldering all of the joints on your bench before installation. Like any curve-to-curve flex track joint, it’s a kink just waiting to happen.
Peco code 100 isn’t quite the same profile as Atlas code 100, so I had to be careful matching up the track height and even the rail joiners. However, once I got everything in place these turnouts work flawlessly.
Thanks MisterBeasley -
yes flex track will be used at all three ends - I usually dont solder turnouts in place to allow for easy removal for maintenace or replacement but I will be extra diligent on making sure no kinks!
So does the real thing. Check out these prototype curved turnouts in this just-issued Model Railroader “online-extra download” by Andy Sperando, “Track and coupler standards for passenger operations.”
http://www.trains.com/mrr/default.aspx?c=a&id=1965
I was amazed at the interaction of curved turnouts & double-slip switches on that 2nd-page photo of entering the Dallas Union Passenger Terminal.
Check the radii of curved turnouts. I only bought #8 for my needs - I had a staging yard on my last layout (10 tracks between 18 and 24 feet long). Since my minimum mainline radius was 32-inches and Walthers/Shinohara #8 turnouts are 32" inside and 36" outside, I used #8 curved turnouts as a minimum for any mainline traffic in staging or on the mainline.
Whenever joining a switch to a curved piece of track, I used fixed curve track. Won’t sproing the turnout outa shape that way. You can bend fixed curve track, BTW, just cut the ties. Dont use tight radius, go easy. Never tried it with a curved turnout. but should work OK.
Funny this should come up now.
I’m in the process of building a curved turnout (basic radius, 610mm) where a single track splits into two parallel tracks (on 65mm centers) with the points at the (approximately) 135 degree point on a curve with a total 200 degree change of direction (horseshoe, yes. PRR, no.) The basic configuration was established by laying flex track along both legs, tracing the tie lines on a piece of card stock, then determining where the point tips, frog point and last long (56mm) tie will go. Approach tracks are all laid with Atlas code 100 flex, and I have carefully put together a Y-shaped super-section, with a hole in the middle where the turnout will be assembled.
Once the wooden ties are cut and caulked into place I will be assembling the frog, points and closure rails inside the borders established by the already-in-place stock rails. The two rails which join at the frog point will be slipped into the plastic tie strip of the Y-section flex - about 12 inches on the outer curve side, about six inches on the inner curve side - to mate with the insulated rail joiners already in place from previous construction. Because I shape my points (like those of the prototype) to ride up on the base of the stock rails, I do not have to locate the exact spot where the points will hit and then file notches in my stock rails (which simplifies construction considerably.)
I do not use jigs, and only (insert Diety of choice) knows what the frog number of this specific turnout really is. I DO use a couple of three-point gauges, and drive spikes with pliers in one hand and my NMRA gauge in the other. When building conventional (one tangent leg) turnouts, I usually specify #5 frog angle - which is a good match for my rolling stock and curve radii. If building a crossover between parallel tracks I may go to #6 if the track spacing is under 60mm.
Because of the way I use long rails (both stock rails are full 36 inch le
On a curved turnout, the frog # is a non-linear indicator of the difference between the 2 curve radii. A small frog # such as #4 means there is a considerable difference - probably on the order of 10" in HO - between the 2 curve radii. This magnitude of radii difference is usually unacceptable, which is why you see most curved turnouts with high frog #s. Probably a #7 or #8 is required to get the radii difference down to 4" in HO, at typical outside curve radius.
Unfortunately, the Walters/Shinohara (and perhaps others) curved turnouts arrive at their outside radius by taking a normal turnout and curving the straight section. This makes for a known outside radius, but the inside radius will be sharper than indicated because the already curved closure rail is being bent further. Chuck’s and other similar methods that focus on the 2 radii when laying out the turnout, and ignoring the frog # will likely result in a smoother flowing turnout that does not violate your desired minimum radius for the turnout.
my 2 cents
Fred W