Large Scale Central

flex track bending question

Track and Trestles
#1

Since I am going to be starting to lay trackwork in the future I am wondering, after bending several pieces flex track for a large curve, there will be one side of track a bit longer than the other, can you take say on a 3 piece curve one inside piece and swap it with an outside piece to keep the ends aligned, or are the actual curves different and that will not work. Looking at my plan and the big loop it makes I am just curious if this can be done to eliminate some of the track that would have to be cut off to keep the end close to each other where the flex meets up with sectional track or switches. I hope this is making some sense as I try to think things out.

Just wondering if it is worth the hassle to do this to eliminate some joints . Starting out it will be track power, but hope to swap it over to battery after i get things running.

#2

The inside rail on any curve is always shorter on any curve. That said as you run your track you should have curves that go both to the left and to the right so the rail ends somewhat catch up with each other. (Unless you just lay an oval of track) I have laid track using long lengths of flex track interspersed with sectional track, but I have eliminated the number of cuts to the rails by only cutting once between sectional and flex sections. i.e. Start at a squared off or even rail ends and add your flex rails without cutting until you come to the next piece of sectional track you are going to use.

The above will work for most, but we have at least one member who measures 40’ intervals on the rails and cuts a groove for the realistic appeal of the clickity clack of the prototype. YMMV(https://www.largescalecentral.com/externals/tinymce/plugins/emoticons/img/smiley-cool.gif)

#3

I used SVRR aluminum track and did not attempt to align the joints thus staggering them. I did this mainly since I thought that the curved sections looked “smoother” and operated better; I’ve yet to have a derailment. I was also careful to space the ties when joining sections to maintain the same spacing as the tie sections themselves. I personally don’t care for that “sectional track” look even though it often becomes less noticeable once ballasted. I also worked to maintain the tie spacing when joining the track sections to the switches (also SVRR).

By the way, my rail is all indoors.

#4

I did as Hollywood (Dave) said, only cutting the rails when I connected to the switches. That made the cut off pieces longer, and more suitable for making up the difference in the next curve. I also cut notches in the rail-heads to get the clickety clack, but for some reason the only clicks and clacks I have are at the joints.

#5

It seems that no one answered one of the questions, in red below.

So, to equalize the differences in rail lengths, you can indeed swap rails between the inside and outside, BUT they are different curvatures, and it is noticeable. So you have to bend the outer rail tighter to go inside, and the inside rail needs to be relaxed a bit to go outside. Kind of hard with a dual rail bender. It can be done, and I have done it for exactly the problem you outlined Pete, and it does indeed “save” some rail.

When I did it, I overbent the track tighter, then put the outer rail on the inside, and then hand “opened” the inner rail and put it in the outer position, and then bolted the sections up together again (I did them in panels of 3) and used the dual rail bender to “smooth things out”.

I used 3 sections assembled, got it right and then mated it to another 3 section and cut rails as needed.

Greg

Pete Lassen said:

Since I am going to be starting to lay trackwork in the future I am wondering, after bending several pieces flex track for a large curve, there will be one side of track a bit longer than the other, can you take say on a 3 piece curve one inside piece and swap it with an outside piece to keep the ends aligned, or are the actual curves different and that will not work. Looking at my plan and the big loop it makes I am just curious if this can be done to eliminate some of the track that would have to be cut off to keep the end close to each other where the flex meets up with sectional track or switches. I hope this is making some sense as I try to think things out.

Just wondering if it is worth the hassle to do this to eliminate some joints . Starting out it will be track power, but hope to swap it over to battery after i get things running.

#6

Thanks Greg, David, the other David and Mark, I was having trouble trying to explain exactly what I was wanting to ask, and hoped in my rambling someone would understand. Greg that was the main question and thanks for explaining how you did it. I need to order some Split Jaw Clamps to help hold everything together and once I get the dirt work finished I will start on track laying and bending. Thanks again for the answers!

Greg, did you swap just one section of a 3 panel curve? should I do the whole curve bent first then start swapping rails? I am using AML flex and it is 6 ft sections, so 3 panels might get a little unwieldy. Maybe i will try one section and then work up as I gain confidence in the process.

#7

David, while my track plan is not a simple loop , its kind of “L” shaped, so for the most part there are more right hand curves than left hand, so with the switches I have off the main lines I was thinking I didnt want to have a bunch of short unusable pieces of quite spendy track being “wasted” , I know I could use it as a car load or as trackside details, but its spendy! and I am CHEAP I mean thrifty.

#8

I understand, I am a cheep bas…frugal too . But by letting the joints get staggered, and only cutting the rails when I had to, to connect to a switch, the lengths of what I cut off were long enough to be usable in making up the difference on the next curve. By doing it that way, I had very little left over when I built my railroad the first time.

#9

disclaimer: the following measurements are measured, not calculated. (as such they are aproximations only)

circumference of circles has to do something with “pi” (3,14).

the different lengths of inner and outer rail are dependent of the gauge (45mm)

on a full 45mm circle the outer rail is longer four times the gauge (45mm x 4 = 180mm or 7.08")

or easier: each 90° curve in largescale is 45mm or 1.77" longer on the outside.

if you have a “L” type circle, you got five 90° curves to the right, and one 90° curve to the left. (no chance, to evade that)

one right and one left cancel each other out. that leaves you with four 90° curves to the right (in your case) so, if ou build everything from flex, you got 180mm/7.08" too much on the inner side. (half a mm for every degree)

your only choice is, in how many pieces you want to saw off this overhang.

just to complicate things (talking LGB geometrics):

for every piece of R1 curve (30°) you have to deduct or add 15mm/0.6" for every piece of R3 curve (22.5°) 12mm/0.47".

being parsimony, one can stagger the rails. that has only two set backs: fiddling a lot with fitting sleepers and a pain in the … fingers when some day, you want to take the track up again.

personally i don’t use flex. (bought about 400 ft of R1 curves very cheap) but i personalize my track into varying curves and straights.

the inner rails of the R1 curves have the same length as straights. so i straighten them and make one foot straight track, that fits into the LGB geometry.

with the longer outer rails i normally bend the inner rails of the future curves into the desired form and push them on the sleeper webbing.

that way i have a fine guide (the empty outer rail"nails") for bending the outer rails.

staggering the connectors as the rails come, i have to saw just once per complete curve.

#10

Pete, the example showed by Korm tells it all, but I was assuming sectional track, where the rails do start out different lengths.

If you start with flex track, both rails are equal lengths, so you just “lose” the “extra” rail on the inner curve.

Greg

#11

being parsimony, one can stagger the rails. that has only two set backs: fiddling a lot with fitting sleepers and a pain in the … fingers when some day, you want to take the track up again.

Yea, there is that.

#12

Pete,

Swapping the rails does not work. The rails in the flex track start out the same length. They do not get shorter or longer when bent. They remain the same length. You can stagger the joints on 2 or 3 or even more sections and then cut the long (inner) track when you need to.

By the way ABTO has a dual rail bender that you can barrow if you like. I also have one I might loan you.

It was good meeting you at Falcon Field. I wish I had not been so busy with the live steam engine at the time. I do hope that the other club members answered your questions for you.

Colin

#13

Thanks for reinforcing my post 2 above yours Colin. (https://www.largescalecentral.com/externals/tinymce/plugins/emoticons/img/smiley-cool.gif)

Staggering the joints gets a little messy when you are trying to use existing sections of ties. I suggest cutting the ties at every joint, no matter which side.

Greg

#14

great answers and lots of help, Thanks Korm, David Colin and Greg, Colin I bought a rail bender a couple of years ago for this reason, so Thanks for the offer, and yes Darryl and the other Darryl( spelled different but don’t remember which way to spell it) were nice to talk to and answered questions that came up. So as they say the check is in the mail!

#15

finally found the pic, i wanted to post here: