Help! How to splice in a turnout on a previously laid flex track curve

[wjstix]

Werl

My track in spiked in place on cork road bed.

If the track is only spiked (i.e., not glued down) it shouldn't be a problem to unspike it and make any adjustments you need. If the cork roadbed is glued down, you may find it easier to add to it where necessary and re-do the section you're working on. It may sound like more work, but may actually turn out to be easier than trying to do gymnastics to leave things in place as much as you would like to.

[MisterBeasley]

I had a loop of subways beneath the streets of my layout.  They were made in HO with Atlas sectional track and flex track, using Atlas snap-switches, mostly.  I did have a couple of Peco double-curved turnouts, which fit nicely with the Atlas track ( code 100) and seemed to be drop-in compatible.  If your N-guage track is similar, you may have an easy time of it.

[Werl]

Hi Pruit, I like your approach, thanks for responding. I have two questions though. I will be approaching the existing curve from the convex side, so shouldn't the "sliding" rail be on the outside? Also, any tips on how to trim a tie or two away from the laid track without pulling up a lot of track or damaging the rail?

[selector]

Yes, it might actually work.  However, my very considered suggestion would be to closely....very closely...duplicate the entire geometry on a separate surface, and run train consists backwards and forwards, trailing and shoving, through the trackage to see where the snags might happen. You can lay sheets of graph paper over what you have, run a graphite pencil over the trackage to get the geometry perfectly duplicated, and tape the graph paper sheets in place, lined up, on a counter or sheet of ply/bench.  Put together the track elements over the defined graphite depictions, insert the turnout in question, and then push and pull typical consists for your rolling stock and engines through all routes.  If it works, especially backing them, and especiallly at some track speed more than yard speed, you should be all set.

[Werl]

Thanks Selector. I do see your point. But i have a question. The curved turnout is a Peco medium with both routes haveing a larger radius than the established curve. I remember the late John Armstrong creating "quasi easments" by adding a 19" R section or the curved route of a snap switch to the end of a 9 3/4" R in main line curve in some of the earlier Atlas publications. Wouldn't adding the larger radius routes on the Peco turnout be the same thing? My XtrackCad simulation shows me how this could work. I will have to research how to add a screen shot here so I can show you. I just need the point end of the turnout to be alligned correcly with the curve.

 

[selector]

You can't do this the way you might envision with a N. American style turnout with the diverging route straight from near where the closure rails meet the frog and beyond.  A curved/double radius turnout would come close, but only if either of the curved routes suffices for your purposes....i.e, with the correct, or approximate, curvature/radius.

If you need to do this, with simply no other option, you should consider a short tangential approach out of the curve already in place to the diverging route...if I understand what you want to do.  You would need passenger cars with diaphragms, for example, to not derail due to curvature or abrupt changes in radius. Or modern, longer, rail stock of all types.  So, you should really rethink this and maybe consider taking up about 2-3' of the curve and reconfiguring it so that the turnout you'd LIKE TO use fits better. 

[Werl]

Thanks Dougless, Pruit and Speedybee, those are all great sugestions. To clarify what i was asking, the new curved turnout will be replacing a No 4 turnout at the end of the curve. The curved turnout will have to be cut in farther back.  The connectting track to the diverging ends will change so their position dosn't matter.   I need the alignment between the laid curve and the new turnout to be as smooth as possible. My track in spiked in place on cork road bed. Thes are all great suggestions and I will report back on which one I used and how it worked out. Thank you!

[speedybee]

To get a nice curve with the least hassle, I would solder a long piece of flex track to each end of the turnout. Then put your turnout wherever you want it on top of your existing track, and hold it in place there with a couple weights (eg canned goods).

Then take the free flex track ends and curve them however you like until they match up with the rails beneath (remember, this assembly is sitting on top of your intact existing track). When you're happy with your new track alignment, secure it there with weights/pins/nails or whatever.

Then you cut through the rails of your new track and the old track beneath it at the spots where they line up nicely together. Remove your old track. Your new track will fit in its place.

[Pruitt]

Werl

Does anyone have any advice for how to cut the curved track and align the turnout correctly with respect to the curve??

Without meaning to be a wise-acre, the best advice I can give is to work very slowly and methodically.

The approach I would take:

1. Figure out exactly where on the curve the entry into the turnout will go.
2. Trim the outside (non-sliding) rail a bit longer (1/4" or so) than you think you need.
3. Curve the flextrack into place, curving the trimmed rail as best you can without kinking it. This is just by hand - you'll get the final curve at final installation.
4. Recheck the outer rail and re-trim it to final length.
5. Solder the outer rail of the turnout to the outer rail of the curve while the end of the flextrack is straight. Sight down the joint before soldering using your eye, or better yet a mirror held at a shallow angle to the rail, to ensure the straight rail is tangent to the curved rail in the turnout at the joint. Solder without moving the joint.
6. Repeat steps 2, 3 and 4 for the inner rail. The inner rail can be a tiny bit shorter - the wheels will roll fine over a small gap between the rails, but it shouldn't be even a tiny skosh too long, as this will disrupt the smoothness of the curve.
7. Install the rail joiner on the inner rail of the turnout, then carefully move the turnout into it's final position, making sure the inner rail of the flex track peoperly slips into the rail joiner. Spike the turnout in place.
8. Now comes the really finnicky part. Using spikes track nails or whatever you prefer, make sure the flex track inner rail is held securely in position so that it flows smoothly into the turnout rail. These are temporary, so you don't have to seat them all the way. They just have to guide the rail into the proper curve.
9. Use the mirror again for a very clear view of the rails at the joint. Make sure there is no kinking at the joiner.
10. Once the inner rails are properly aligned, solder the inner rails together at the rail joiner.
11. You should be able to remove the spikes or whatever you used to hold the inner rail in position. 

That was a bit long-winded, but I hope it helps!

[Doughless]

I'm not sure what you are asking, and I suspect others aren't either looking at the lack of responses.

Assuming the track is affixed to the road bed (if not I would just unsolder the curve and reinstall it with the turnout), you can use a razor saw to cut the flex track and it will hold its place just fine.  Just lay the turnout over the flex to mark the four cuts correctly.

Before installing, you will need to slide joiners all the way under the rails (either the flex track or the turnout), before the new piece will fit inot the curve.  There is not other way to get joiners into the joint, so they have to be placed under the rails and above the ties to not get in the way of installation, yet be able to slide onto the rails of the opposing tracks.

[amyscriber]

You should use a rail nipper or a similar tool, carefully cut the track at the marked spot. Ensure that the cut is clean and straight.  Moreover, place the curved turnout in the desired position, aligning it with the existing curve. Adjust the position of the curved leads on the turnout to match the curve and the track alignment.

[Werl]

I know about and have used the method for joining Atlas N flex track on a curve (i.e. leave the end of the flex track straight, trim rails even, attach and solder the next flex track section). However this method does not seem appropriate for splicing-in a curved turnout on a finished laid curve. Does anyone have any advice for how to cut the curved track and align the turnout correctly with respect to the curve??