Curves into a turnout - how forgiving will they be?

I dont see too much of a problem but you might want to consider backing up the turnout on the left a few inches to reduce the angle between the two turnouts

First of all, did you print your computer-drawn plan at full size and then transfer that template to the subroadbed? If not, you should because if your computer program is good, you should be able to build what you drew with very, very little adjustment.

Secondly, yes, you can definitely lay track carefully enough so that you can have curves leading to and from turnouts (I have many). The operative word is "carefully." One way to help you to lay smooth transitions from the turnouts to the flex is to use Ribbonrail metal guides (available both straight and in various radii) that fit between the rails to align the turnout with the flex when laying the track. And of course, give all your transitions the eyeball test to verify they are smooth without kinks.

Dante

I think you should dump the sectional track and use the flex track, that will be the final product anyhow, to plan your track position. The flex track will allow you to create easements where the track transitions from the turnouts. You will need to be very careful because if you allow the easements to be too long you will end up with too small a radius in the center of the curve, but you will be able to eliminate the abrupt changes which the sectional track is causing now.

If I can suggest, in the picture that you posted, the distance between the inner track and the outer turnout needs to be reduced in order to keep your curves within acceptable dimensions. If you move the outer turnout closer to the inner turnout you will be able to reduce the distances between the tracks and actually increase the radii of the curves. I could be wrong, but I have played with the same sort of issues for a long time with my RR CAD program.

Bottom line is that I think that using the sectional track to try to work out the track plan is causing you a lot of confusion.

Dave

Are those turnouts both straight L and R? Or is one curved. Because this would work a lot better with curved turnouts.

hominamad

I figured it would be best to place all the turnouts down, and then draw the connecting tracks between them. I'm using sectional track as a template to help me redraw the curves, but will be using flextrack in the end.

Below is a photo of one of the dicier areas. I know I can get all of these pieces to connect with flextrack, but I want to make sure I won't cause tons of derailments as a result. 

My first piece of advice is to drop the idea of using sectional track as a template. The most effective tool that I have ever used for this purpose is the Ribbonrail Metal Track Alignment gauges.  I use the 10" version rather than the 5" version. The longer version simply provides a greater degree of accuracy when laying track.

My second piece of advice is to use flextrack from the outset.  Using the Ribbonrail gauges as your guide, experiment with the placement and curvature of the flextrack.

My third piece of advice is to solder the connections.  I normally do not solder sections of flextrack together, and I do not solder flextrack to turnouts. However, I do solder flextrack sections together on curves to avoid kinks.  It is the kinks that cause derailments.  For that reason, I do solder the flextrack connections to curved turnouts.

When purchasing Ribbonrail alignment gauges, buy a few on either side of the desired radius.  For example, if your curves are 22" radius, buy not only the 22" radius gauge but also the 18" and 20" as well as the 24" and 26' radius gauge. That way, you will be able to visualize problem areas as well as trouble free areas.

Lastly, remember that curved turnouts, properly installed, are no different than curved flextrack.  Select the proper radius for your particular layout and for your motive power and rolling stock.  If it works on a 22" radius curve of flextrack, it will work on a 22" curved turnout.  If it derails on a 22" radius curve of flextrack, it will derail on a 22" curved turnout.

Remember, the secret to a curved turnout is to avoid kinks at the connections to the adjoining track.

Rich

Yes, the issue is kinks.  You need to be absolutely sure the rails meet on a perfect tangent, so the curve is completely smooth.  If there is a slight discontinuity in the curvature, that's where you will have trouble.  This is true of any track joint, incidentally, but the problems are more pronounced at turnouts because there is no room for recovery when you're headed into points and frogs.

Flex track is more prone to kinks, because it wants to "kick out" and there is always a sideways force against the rail joiner.  I also like to solder joints where flex meets turnout on a curve.  I do this on the workbench, or at least with the flex track loose so that I can solder a straight piece of flex track and then bend it to shape after it's soldered.

Another thing to be wary of is vertical kinks.  Again, these are more of a problem with turnouts.  Your roadbed and subroadbed should be perfectly flat throughout the lead-in, turnout and lead-out so that you wil not have a vertical kink.  This type of kink, by the way, will be more of a problem with a long steam engine with a long fixed wheelbase, which will ride up and then suddenly tip forward rather than negotiating the kink with smal play in the trucks.  "Flat" is not the same as "level," by the way.  Level is good too, but flat is more important.  With care, there's no problem having a turnout on a slope.

I, too, use RibbonRail gauges.  This one is 18-inch radius.  I'm using it here to get a good joint between two sections of Proto87 girder rail for street running:

I made some curve templates, radii from 22" to 36", from brown paper I got at Home Depot.  It took awhile to draw outer lines on the paper and then cut them out.  But these arcs were handy to finalize arcs drawn on the plywood.  I also have a less than 6' x 10' layout, with a number of curved turnouts. 

I had marked my plywood with 6" squares, used to place, but not glue down, the turnouts per my XTrackCAD plan.  I started at critical turnout spots, then established the radius curves departing them, drawing the arcs connecting to turnouts.  With the paper templates, I could vary a curve radius as needed (drawing on the plywood, then putting down the cork).  Once the cork is down there is a bit of room for final fiddling with the final cutting and gluing of the track.  I have 2 curved crossovers much like yours, with a piece of flex between the turnouts.  I got one of them slighlty misaligned/spaced, forcing the intermediate flex piece to be a bit too sharp and variable curve (appearance), so getting those nice with trial and error is important.  The curves outward from the crossover (turnouts and connector flex piece), if flextrack, can adjust to the crossover "unit" as needed.  I'd suggest building the crossover unit track pieces to your satisfaction and use it (just pin it down temporarily) to establish outgoing connecting curves; i.e., work outward from the crossover unit.  As some others note, I soldered curve track joints except at turnouts.  Learn that method if you don't know it; i.e., solder it with the existing piece glued down except the last 6" or so temporarily straight, then establish the curve and continue gluing down most of the extension piece. 

In general, I would get an area of track as I wanted it, connect it temporily on the plywood and mark the outer ties line with a pencil.  Then, mark (by eye) the centerline periodically.  Then lay the cork along the centerline.  Then lay (glue with caulk in my case) the track, working outward from turnouts.  I glued my turnouts a tad with a bit of caulk in a few spots. Do ensure that the curved turnouts, especially, are laid flat as any twist can contribute to problems.

I used for my code 83 the N80 rail joiners.  They need some fiddling to get on but make for a more stiff connection at turnouts where not soldered. 

Just take your time and use trial and error until it's to your satisfaction.

EDIT: An afterthought. I had lots of trouble with derailments on my 1980 layout, flextrack and Atlas turnouts.  I think the problem was just plain poor trackwork, more so than rolling stock issues.  This time I studied it lots before proceeding and it has been pretty good, just a few unique problems, mostly solveable.  Beside lots of help from the forum, I also found a couple of booklets useful, even to stimulate more specific questions.  I recommend "Basic Trackwork for Model Railroaders" and "How to Build Realistic Reliable Track", both from the MR store (I presume they are still available).  

http://www.kalmbachstore.com/12254.html

http://www.kalmbachstore.com/mr6090801.html

From the pics it looks like you're trying to connect to curved turnouts with 22" radius track.  The radius on those turnouts look  larger than 22".   If that's the case you should be OK.

Richard

Thanks everyone. A few things:

- The turnout on the left is a curved turnout. The other ones are straight.

- I wasn't really able to print out a true-to-size drawing and lay on the wood because I never had a single sheet of wood to work with. The way I built the bench work, the subroadbed were all individual pieces. So I divided it into sections, measures them out, cut and reassembled. Below is a pic of the full benchwork.

I was figuring that attaching a 22" radius section piece to a turnout, would pretty much be guaranteed to be a good transition - that's why I was using it as a template. In my old layout, I had problems with flex track coming into the turnout on a weird angle and the trains had no chance. I thought by using sectional as a guide I would avoid that.

One thing I'm still not clear about re: easements - are they just for show? Or is a necessary thing to have for smooth operation? I figure there must be a lot of people who only use sectional track, so I figure it must be possible?

About the ribbon rail gauges - I"m still a bit confused about how these are used. Does it go in between the rails to form the curves? Or do you use it as a template to trace with? If it's just a template, how is that different from using a piece of sectional?

Sorry - one last question! About soldering - someone posted a video on Youtube about how they do their flex track curves. They offset the rails by a few inches so the connections are staggered. He claims that you don't need to solder with this method and it's better becuase it allows the track to expand with weather changes, etc. Any comments about this technique? I was planning on doing this but was thinking I would still need to solder the connection to the turnouts anyway. Here's the link to that video: https://www.youtube.com/watch?v=MyucN1tV0zY

For anyone interested, here's a pic of my trackless benchwork:

hominamad

About the ribbon rail gauges - I"m still a bit confused about how these are used. Does it go in between the rails to form the curves? Or do you use it as a template to trace with? If it's just a template, how is that different from using a piece of sectional?

One way is to form the curves by moving the gauges as I nail down the track.

The other way is to form the curves and then use the gauges to verify that the curves meet the minimum desired radius.  For example, if I want a minimum 32" radius curve, I will form the curve with flextrack and then fit the Ribbonrail gauge between the rails.  If the formed flextrack curve is broader than the curvature of the 32" radius curve, then I know that I am good to go.

Rich

hominamad

Sorry - one last question! About soldering - someone posted a video on Youtube about how they do their flex track curves. They offset the rails by a few inches so the connections are staggered. He claims that you don't need to solder with this method and it's better becuase it allows the track to expand with weather changes, etc. Any comments about this technique? 

When I do it, I remove 2 or 3 ties on the end of each piece of flextrack, lay both pieces of flextrack straight, no staggered rails, and then solder the connections.

Rich

hominamad

 

For anyone interested, here's a pic of my trackless benchwork:

 

Personally, I would use sectional track as much as I could with that benchwork.  I think its harder to work with flex track in short, tight sections.  Sectional track already provides a consistent curve from end to end.

But you will have to clip some sections to get the proper length, and you will probably have some areas that will require flex track where the sectional pieces can't help but kink at the joints of turnouts.  As others have said, that's what's to be avoided.  Also, I wouldn't worry about easements on curves, but easements for grades would be helpful, especially for the transition at the bottom of the pic.

In your first pic, the curved turnout on the left needs to be slid way up the left side of the pic.  The angle is too sharp to meet the tangent of the straight turnout.

And I would solder every joint.

In general I agree with Rich's approach, but although I solder joints on curves, I do not solder joints to the turnouts (to facilitate possible future removal). I use Walthers/Shonohara Code 83 turnouts and flex fastened with spikes, not caulk or track nails. Spikes help make secure the rail alignment on both sides of joints. The Ribbonrail gauges are most useful between the rails, especially spanning the junction between the turnout track and the connecting flex to encourage a smooth transition.

As for using full-size printouts of your CAD drawings to layout guidelines on the subroadbed, you can do that with your cookie-cutter benchwork: just cut the printout into strips following the track shapes.

Dante

I would also reccomend soldering the flex track both on the curves and into turnouts where a curve starts shortly after the turnout.  If you need to remove it later, you can always desolder it (using Desoldering braid, available from your local electronics supply store).  Just make sure when you are soldering you use a heat sink such as a pair of locking tweezers or alligator clips to dissapate the heat away from the joint.  This will minimize the melting of ties in most cases. 

Also, is your track plan based on the MR Virginian project railroad from a few years back?

hon30critter

I think you should dump the sectional track and use the flex track

 

I agree. I discovered flex track and haven't used sectional track since.

JERRY PAAUWE III

I dont see too much of a problem but you might want to consider backing up the turnout on the left a few inches to reduce the angle between the two turnouts