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beginning of the the track plan tutorial.
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[ ••• ] (This symbol means that a screenshot is shown here on the main tutorial pages. If you have printed this page you may wish to tick off the screenshot for each section as you complete it.)
This is a mini-tutorial.
Please refer to the general notes about using these tutorial pages at the
beginning of the the track plan tutorial.
A return curve is a curved length of plain track which returns the diverging road of a turnout back towards the main road, so that the two roads become parallel or concentric (marked with yellow arrows in screen A, templates 1 and 2).
A return curve is often employed to form the end of a running loop, or to make a junction between double and single track, or to access an island platform.
screen A: [ ••• ]
Screen A shows six different return curves, each attached to a left-hand B-6 turnout in S4/P4 gauge. The main road in each case is straight for simplicity in the diagram, but it could equally well have been curved on a fixed radius (but not in all cases on a transition curve or containing a slew - see later).
There are four different ways to create a return curve in Templot:
Each of these methods has its pros and cons, summarised in the table below:
| return curves in Templot : | tools > make return curve |
parallel crossing |
do it yourself ( transition ) |
do it yourself ( slew ) |
| the return curve is a separate plain track template which can have a turnout inserted, and over which another can be aligned. |
 |
no | |
can be combined with the loop track |
| the main road can be on a transition curve, or contain a slew. |
no | |
|
|
| the return curve radius and length of intervening straight can be adjusted. |
no | |
|
alignment is variable |
| the method can be used with a curved crossing type of V-crossing. |
yes, but not recommended |
no | |
|
| the method can be used with a generic crossing type of V-crossing. |
|
no | |
|
| the method is quick to use. |
|
|
not very | no |
Method 1. tools > make return curve :
This function creates the return curve as a separate template which is a length of plain track of fixed radius. The radius is always set to the maximum which will fit between the turnout and the centre-line of the adjacent track on the turnout-side (TS), the spacing of which can first be set by clicking the geometry > adjacent centres... menu item.
In screen A, template 1 shows the result of using the tools > make return curve menu item when the adjacent track spacing is set to its pre-set startup setting, which for this S4/P4 gauge template is 44.67 mm centre-to-centre (11' 2" scale for 6' way between the inner rails).
For template 2, I changed the TS adjacent track spacing to a much wider setting, 100 mm centre-to-centre. Using make return curve then produced a much longer and easier return curve.
Because the return curve template is a separate plain track template, independent of the turnout, it can be modified and adjusted like any other, have a turnout inserted in it (track > insert turnout in plain track menu item), or after copying to the background have a new current template aligned over it.
There is however a limitation on the use of the make return curve function. It is not available when the main road of the turnout is on a transition curve, or contains a slew. In these cases, one of the other return curve methods must be used.
Method 2. parallel crossing :
Templates 3, 4, 5, and 6 in screen A show return curves which are part of a turnout which has a parallel crossing. These are all single templates, and the return curve is an integral part of them, not a separate template.
In template 3 the adjacent track centres have been set at 44.67 mm, and in template 4 the adjacent centres have been increased to 100 mm. You can see that in both cases the return curve radius is the same, corresponding approximately to the radius of the turnout and similar to that in template 1. The difference in template 4 is that a length of straight has been introduced to make up the extra track spacing.
These two templates 3 and 4 illustrate the most common way of using a parallel crossing.
But in templates 5 and 6, both the return curve radius and the length of intervening straight are different, and this is done by changing the parallel crossing track centres dimension independently of the adjacent track centres dimension. The screens below show how these settings are used.
screen B: [ ••• ]
For a parallel crossing, click the track > crossing... menu item, and then select parallel crossing in the list on the crossing selector window which appears (screen B). Change the parallel track centres option to other... so that we can set this dimension for the parallel crossing independently of the current adjacent track spacing dimension. Then click OK.
screen C: [ ••• ]
On the data-entry form in screen C, set the turnout road track centres to, say, 100 mm. Note that this is not the same thing as the adjacent track centres setting, which remains as previously set. This dimension applies only to parallel crossings, and only when the other... option is selected (screen B).
screen D1: [ ••• ]
Screen D1 shows the result. The turnout now has a return curve linking the turnout road to parallel track at 100 mm centres. Because we haven't changed the adjacent track centres dimension (which remains at 44.67 mm), the straight section between the turnout and the return curve is the same length as it would have been if the parallel track centres had been set to that dimension. The additional spacing out to 100 mm centres is made up by a long easy return curve of 5441.34 mm radius. These dimensions are arrowed in screen D1.
Checking the track menu (or the right-click menu) we see that the length free option is selected. This means that despite appearances there is no exit track (or approach track) on this template, which is set to the free overall length. The free overall length of a parallel crossing template is set to the end of the return curve, i.e. the position at which both tracks become parallel (or concentric in the case of a curved main road) (arrowed). The ends of the tracks at this position are the MRP (Main-road Return Point), and TRP (Turnout-road Return Point), and the fixing peg can be set at these positions if desired (adjust > set peg options > menu items).
This template is now the same as template 5 in screen A.
screen D2: [ ••• ]
If the F4 overall length mouse action is now used, exit tracks can be added to both tracks, or both can be shortened back, but it is not possible for the lengths of the two tracks to differ.
In screen D2, if the F6 curving mouse action is tried, you will see that both tracks are adjusted accordingly, and it is possible to set a main road curving radius such that the return curve is actually straight, or curved in the same direction as the main road, positive or negative (showing negative for this left-hand turnout). I have set the peg at the TRP position. (The peg indicator shows N because there is no keyboard shortcut for this position).
Remember that this is all one single template (which could also have some approach track added). It could also be on a transition curve in the main road, or contain a slew.
screen E: [ ••• ]
Now in screen E click the geometry > adjacent centres... menu item,
screen F: [ ••• ]
and in screen F set the turnout-side adjacent track centres to 100 mm, matching the parallel track centres entered previously. The main-side dimension is not used here and can remain unchanged.
screen G: [ ••• ]
Screen G shows the result. The return curve is much shortened by having a longer intervening straight section and a much smaller radius. Compare the arrowed dimensions with those in screen D1.
This template is now the same as template 4 in screen A.
screen H: [ ••• ]
Screen H explains what is happening. I have drawn a yellow line at 50 mm from the main road centre. This would be the centre-line between the tracks if we created double track at the present adjacent track spacing dimension of 100 mm. In generating the straight portion for a return curve in a parallel crossing, Templot always sets the length of this straight so that it is equally disposed about the centre-line between adjacent tracks, calculated from the fine-point of the turnout. In other words, the two blue arrows in screen H are equal in length.
Note carefully that the dimension used to make this calculation is the current adjacent track spacing setting, not the actual parallel track spacing which is being used for the loop track. Here these two dimensions are the same (100 mm), but as we have seen in screens D1 and D2 they need not be so.
When the adjacent track spacing is less than the parallel track spacing (as in screen D1), a longer, easier return curve is produced, with a shorter intervening straight section.
When the adjacent track spacing is the same as the parallel track spacing, and the main road is straight (as here in screen G), the radius of the return curve is approximately the same as that of the turnout. (Approximately, because the turnout road within a turnout is not a single curve.)
When the adjacent track spacing is greater than the parallel track spacing, a tighter return curve radius is produced. This can easily be taken to extremes, as shown in template 6 on screen A, where the adjacent track centres exceed the parallel track centres by only 15 mm, but the curve produced is unusable.
Summarising for a parallel crossing : To change the length of the intervening straight section, change the adjacent track centres dimension (geometry > adjacent centres... menu item). To change the radius of the curve section, change the parallel crossing track centres dimension (track > crossing... menu item, then other... option button). |
Method 3. Do-it-yourself return curve (using a transition curve) :
In the next part of this tutorial we shall create a return curve which is similar to that for a parallel crossing, but as a separate template which can be modified and adjusted in the same way as any other template.
screen 1: [ ••• ]
Our object in this part of the tutorial is to create a short return curve template in S4/P4 for this B-6 turnout, with the track spacing at 100 mm centre-to-centre. For simplicity in the diagrams I have assumed a straight template (main road is straight), but these methods work equally well for a fixed-radius curve or a transition in the main road.
In screen 1, extend a reasonable length of exit track (F4 overall length mouse action), and then put the peg at the TVJP (Turnout-road Vee Joint Position) (CTRL-6), as shown. Make a note of the minimum radius in this turnout (1167 mm, arrowed). We shall later need to set a radius for the return curve, and we may as well use this figure.
Click the geometry > adjacent centres... menu item,
screen 2: [ ••• ]
and then set 100 mm for the turnout-side adjacent track centre-to-centre spacing (screen 2).
screen 3: [ ••• ]
In screen 3, make a length of double track on the turnout side (tools > make double track TS menu item),
screen 4: [ ••• ]
and put it on the background (store & background menu item, here on the right-click menu) (screen 4). This template is needed temporarily as an aid to aligning the return curve.
screen 5: [ ••• ]
The basis of our return curve will be a transition curve template, so click the geometry > curved (transition) > easement from straight menu item as shown in screen 5 (in which the current template remains hidden after copying to the background).
screen 6: [ ••• ]
So press F12 to see it again, looking like this (screen 6). If what you are seeing is unfamiliar, please click transition curves and read the notes about them before proceeding.
Now click the geometry > curving data... menu item,
screen 7: [ ••• ]
and enter these dimensions (screen 7). The initial radius is already straight (pre-set), and we have decided to use 1167 mm as the final radius for the return curve section. The length along initial radius is an arbitrary guess at 150 mm (we are about to change it). The length along transition zone is set to zero for this template, making the straight section tangential with a simple fixed-radius return curve section.
All these dimensions can be changed to suit different requirements as you wish. Click OK to continue.
screen 8: [ ••• ]
Screen 8 shows the result. Because we set the transition zone length to zero between the straight and the curved section, the transition start and end markers are superimposed, as shown (arrowed).
Now click anywhere on the turnout template to bring up its menu, and click the peg / align current > notch under peg and shift current menu item.
screen 9: [ ••• ]
The result in screen 9 is that the current template is pegged onto the background turnout template. (We previously set the turnout's peg at the TVJP position in readiness, see screen 1.)
Now we want to change the length of the straight section (shown with blue arrows) until the curved section is exactly tangential with the temporary adjacent track. There is no automatic function to do this, but by zooming in close we can do it very accurately by eye on the screen. Select the adjust > mouse actions: current > move transition start (SHIFT+CTRL-F3) mouse action.
screen 10: [ ••• ]
Then in screen 10 adjust the position of the transition markers (arrowed 1) until the curve is approximately tangential with the adjacent track (arrowed 2).
screen 11: [ ••• ]
Zoom in closer (screen 11), and shorten the template (F4 overall length mouse action) until there is a more convenient overlap from the tangent point of, say, three sleepers-length (arrowed blue).
screen 12: [ ••• ]
Zoom in much closer (screen 12), and note the remaining discrepancy between the track alignments (arrowed). We need to make a further slight adjustment to the transition start, but before doing so it will be easier to see what is happening if we remove the timbering from current template.
There are several ways to do this, a convenient one is the pad > screen refresh options > skeleton mouse draw menu option, which draws the current template in skeleton form during mouse actions. This option can be toggled on and off at any time by pressing its single-key alternative keyboard shortcut, which is the ; (semi-colon) key. There are many more of these single-key alternatives, they are shown on the Function Key Chart (help > print F key chart menu item to print it out).
screen 13: [ ••• ]
Now in screen 13 make the final adjustment to the transition curve (SHIFT+CTRL-F3 transition start mouse action again), until the rail-edges and track centre-lines are exactly aligned (blue arrows). Notice that it is not necessary to have the transition markers actually visible while adjusting their position.
screen 14: [ ••• ]
Then in screen 14 make a further adjustment to the overall length, terminating the return curve at the approximate position of the tangent point. The exact position is not important, and at this degree of magnification can be easily judged by eye.
screen 15: [ ••• ]
Screen 15 shows the finished return curve template, which we can now put on the background.
screen 16: [ ••• ]
Now we can shorten or delete the temporary adjacent track as necessary. First delete to current (screen 16),
screen 17: [ ••• ]
then swap the peg to the opposite end by clicking the peg indicator (arrowed) (or CTRL-1), and shorten the template as necessary using the F4 overall length mouse action (screen 17). A slight gap or overlap is of no consequence.
screen 18: [ ••• ]
The end of the return
curve was set by eye only. If it is desired to peg further templates at this
position, for the maximum accuracy it is better to set the notch from the
adjacent track template rather than from the return curve. I therefore swapped
the peg back to this datum end
(CTRL-0) before
putting the notch under it
(DIVIDE key on
the number pad). For more information about the peg & notch functions,
click peg & notch.
You can see that I overlapped the templates slightly, the vertical black line is the end marker for the return curve template (screen 18).
screen 19: [ ••• ]
Screen 19 shows where we have reached. This return curve is essentially the same as the one which we previously created using a parallel crossing, see screen G and template 4 in screen A. The important difference is that this return curve is now a separate template in its own right, which means that we can use all the usual Templot functions on it.
screen 20: [ ••• ]
As an example in screen 20 I did delete to current, then track > insert turnout in plain track, then track > hand > invert handing, and CTRL-F9 maintain length mouse action. Possibly also tools > swap current end-for-end. None of this is possible when the return curve is part of a parallel crossing (as in screen G).
screen 21: [ ••• ]
Now in screen 21 I have repeated the whole exercise for a turnout having a negative radius of 4000 mm in the main road. As you can see, the original return curve needs further adjustment.
screen 22: [ ••• ]
In screen 22 I first lengthened the template (F4 overall length), and then shortened the length of the straight section (SHIFT+CTRL-F3 move transition start) until the return curve was again tangential with the temporary adjacent track.
But unless space is tight, there are other adjustments which we could make. For example, it is possible to get an easier curve by putting the straight section on a gentle curve, or by introducing a finite (non-zero) length of transition zone. We might also decide to change the radius of curve section.
We can now immediately adjust any or all of these four transition settings by mouse action, or enter some trial dimensions directly as a starting-point.
screen 23: [ ••• ]
I chose the latter course and clicked the geometry > curving data... menu item to bring up the data-entry form (screen 23), and then entered these dimensions:
The former straight section I changed to an initial radius for the transition of 4000 mm, matching the radius at this point in the turnout-road (for a regular crossing as here, this is curved to the same radius as the main-road).
For the return curve I entered an easier final radius of 1500 mm.
I then guessed trial dimensions of 120 mm for the length along the initial radius, and 240 mm for the length of the transition zone.
screen 24: [ ••• ]
Screen 24 shows the result, an easier return curve which is not very much longer than before. It needs a little further adjustment. To do this there is a choice of four transition curve adjustments:
I chose the second option and adjusted the length of the transition zone (screen 24).
Options 1 and 2 mouse
actions can be more conveniently selected using the single-key shortcuts,
which are the
[ and
] (square brackets)
keys respectively.
When using the
F6
curving mouse action to adjust the radius, clicking the
hollow-triangle mouse action
symbol on the mouse action
panel toggles between the 1st (initial) and 2nd (final)
radius. Or these can also be conveniently selected using the single-key
shortcuts, which in this case are the
- (minus) and
= (equals) keys
respectively. These keys can be pressed while the mouse action is in force.
screen 25: [ ••• ]
Screen 25 shows the final result, after zooming in as before (screens 11-14) to make the final adjustments to the alignment and overall length.
Method 4. Do-it-yourself return curve (using the slew functions) :
In the final part of this tutorial we shall create a return curve by means of a completely different method, which is to slew the end of the loop track into line with the turnout.
This involves pushing the slew functions somewhat beyond their intended purpose as a means of "tweaking" alignments, but if done carefully can produce an acceptable return curve. The advantages over the other methods are that the length of the return curve can easily be set initially to fit the available space, and the return curve can be combined in one template with the loop track, which is useful when you want to insert a turnout which bridges the end of the return curve.
screen 26: [ ••• ]
In screen 26 I have again started with a left-hand B-6 turnout on a negative curve of 4000 mm (F6 curving mouse action), in S4/P4 gauge (control > gauge and scale > menu items), and extended the overall length to approximately 1200 mm (F4 overall length mouse action).
Then I clicked the geometry > adjacent centres... menu item,
screen 27: [ ••• ]
and I again set the adjacent track spacing to 100 mm (screen 27).
screen 28: [ ••• ]
With negative curving a curved crossing is often appropriate, and will be useful here as I want a fairly short return curve. Click the track > crossing... menu item to bring up the V-crossing selector window (screen 28), and then select curved crossing in the list.
For more information about curved crossings and the different types of crossings, click the ? help info button (or see screens 36a and 37 in the track plan tutorial).
screen 29: [ ••• ]
Then tools > make double-track on the turnout-side (TS), as before (screen 29).
screen 30: [ ••• ]
Now in screen 30 we have our adjacent track, with its CTRL-0 datum end at the left (arrowed). It will be much easier to adjust the slewing if the datum is at the opposite end, so click the tools > swap current end-for-end menu item.
Note carefully
that this is not the same thing as simply moving the peg to the other end
of the existing template in the usual way by clicking the peg
indicator or pressing
CTRL-1. We want
instead to create a completely new template on the same alignment as before,
but with the
CTRL-0
datum end at the opposite end, as shown (arrowed) in screen
31. Note that in this process the template also swaps to the opposite hand.
screen 31: [ ••• ]
Now we are ready to apply a slew to this template. There are two slewing modes, using different maths to calculate the alignment within the slewing zone. We will first try slew mode 1, so click the geometry > slew (nudge) > slew using mode 1 menu item (screen 31).
screen 32: [ ••• ]
Screen 32 shows the result. If what you are seeing is unfamiliar, please click slewing and read the notes about the slew functions before proceeding. (Note that compared with the diagram in the slewing notes, our slewed template here is facing in the opposite direction, with the unslewed section on the right.)
(The length of the slewing zone and the amount of slew may initially be different on your computer. This is of no consequence, because we are about to change these settings.)
Now we can use the SHIFT+CTRL-F5 slew start mouse action to position the slew start marker (arrowed 1) at the desired position for the end of our return curve. Because we are not changing the slewing length while we do this, the slew end marker (arrowed 2) moves also.
screen 33: [ ••• ]
I settled on the position shown (screen 33), with an unslewed length from the datum end of the template on the right of approximately 350 mm. Notice that the slew end marker (arrowed) may now be outside the visible part of the template, which no longer contains the whole of the slewing zone.
screen 34: [ ••• ]
Now we use the CTRL-F7 slew amount mouse action to shift the slewed track sideways until it is approximately over the turnout road exit on the the turnout (screen 34).
screen 35: [ ••• ]
Then in screen 35 we zoom in close on this area so that we can set the alignment by eye with greater accuracy. This is much easier to do if the timbering is temporarily switched off for the current template (geometry > timbering > no timbering menu item).
The procedure now is to alternate between the SHIFT+CTRL-F6 slew length and the CTRL-F7 slew amount mouse actions to achieve the required alignment. This will need some practice at first. It is helpful to first adjust the slew length to get the rail-edges and track centre-lines approximately parallel at the join, as shown (yellow arrows), and then adjust slew amount to bring them into line. You will probably need to alternate between the two adjustments a few times to get an exact alignment. Notice that it is not necessary to have the slew markers actually visible while adjusting their position.
It is convenient
when swapping back and forth between two mouse actions to press the
BACKSPACE key (for
repeat last action), or to click one of the
hollow-triangle repeat last
action symbols (arrowed blue in screen 35). For the repeat
last action functions to work as intended the
mouse action panel should remain
visible, i.e. don't explicitly cancel the mouse action which is in force
before swapping to the previous one.
Or use instead
the single-key alternative shortcuts, which in this case are the
# (hash) key for
slew length and the
7 key (on the main
keyboard) for slew amount.
screen 36: [ ••• ]
Screen 36 shows the alignment I achieved. The current template rail-edges (showing in black) are aligned over those on the background turnout template (showing in blue) (arrowed 1), and likewise for the track centre-lines (arrowed 2).
Notice that it is not likely that you will achieve an exact match over a long length (arrowed 3), because the slewing mathematics do not generate circular arcs for the curves (but see also later for mode 2 slews). It is sufficient to achieve a reasonable match over a length approximately equal to the track-gauge as shown (arrowed 4).
The information panel shows the dimensions which I finally used. It is likely that your figures will be similar, but unlikely that they will be exactly the same. If you are struggling, you could try directly setting these dimensions initially as a starting point (geometry > slew (nudge) > slewing data... menu item).
If it proves difficult to find the alignment, it can be helpful to temporarily zoom back out, and possibly to move the slewing start position a little (screen 32).
Remember that this view is several times larger than full-size. There is little to be gained by striving for greater precision than that to which you can build the finished track.
screen 37: [ ••• ]
Reinstating the timbering and zooming back out (SHIFT-F11 or the . full-stop key) shows the complete return curve (screen 37).
screen 38: [ ••• ]
Then in screen 38 we shorten the template back to the join (F4 overall length mouse action). A slight gap or overlap at the join is of no consequence.
screen 39: [ ••• ]
Screen 39 shows our finished slew-method return curve. Note that the slew end marker remains visible on the left, even though the track does not reach that far.
If you might want this template again, now is the time to put a copy of it in the storage box (control > store this) because we are going to change it shortly.
Compare this curve with the transition-method return curve which we created earlier (screen 25).
screen 40: [ ••• ]
One important difference between the two methods is that the slew-method return curve can be combined with the loop track in one single template. This is useful when we want to insert a turnout which bridges the end of the return curve, which is quite often needed. I have shown an example in screen 40.
To do this on a transition-method return curve, or one created using tools > make return curve, would require half-turnouts to be duplicated and blanked off as necessary on two separate templates. (And it is not possible at all for a parallel crossing return curve.) Don't forget that the tools > make crossover function is also available when the loop lines are more closely spaced than we have here.
screen 41: [ ••• ]
In the final part of this tutorial we shall experiment with the alternative mode 2 slew functions. Screen 41 shows the effect which can be achieved, showing our previous return curve (mode 1) in blue, and an alternative mode 2 return curve in black.
Generally for a mode 2 slew the curvature at each end of the slew is eased (arrowed 1), at the expense of a more prominent reverse curve at the centre (arrowed 2). But the extent of this effect can be varied by means of the adjustable mode 2 slew factor. (There is no slew factor for mode 1).
screen 42: [ ••• ]
In screen 42 click the geometry > slew (nudge) > slew using mode 2 menu item.
screen 43: [ ••• ]
After extending the overall length (F4), screen 43 shows the result, which is a more pronounced reverse curve effect.
screen 44: [ ••• ]
Now in screen 44 with timbering switched off again, we repeat the process of adjusting the slew length and slew amount alternately to achieve an alignment with the turnout, as we did earlier in screen 36.
For the present we have left the mode 2 slew factor at its pre-set value of 100 (arrowed red). Notice that we can get a matched alignment over a somewhat longer length than before (arrowed blue). This is because for mode 2 the slewing maths approximate more closely to circular curves than for mode 1.
screen 45: [ ••• ]
Then shorten the overall length to the join as before (screen 45).
screen 46: [ ••• ]
Screen 46 shows our new mode 2 slewed return curve. Compared with the mode 1 version showing in screen 42, this one has a more sinuous alignment.
Generally for any given length a mode 2 slew will have easier curvature than mode 1, but care is needed to avoid a severe reverse curve which may cause buffer-locking problems. Bear in mind that we are here pushing the slew functions somewhat beyond their intended use, and each case of a return curve needs to be judged on its merits.
screen 47: [ ••• ]
Before experimenting with the mode 2 slew factor, we can put this one on the background for comparison. I used the right-click menu in screen 47.
screen 48: [ ••• ]
Now I lengthened the template again, and in screen 48 I selected the adjust > mouse actions: current > adjust mode 2 slew factor mouse action. (Sorry there's no shortcut for this one.)
screen 49: [ ••• ]
In screen 49 you can see the effect of increasing the slew factor. At a factor of around 150 the curve becomes even more sinuous, and will require a reduced slew amount to restore the alignment (arrowed blue).
I have removed all timbering and track centre-lines on this screen to make things clear (control > background list menu item and untick the boxes for the background templates, showing here in blue).
screen 50: [ ••• ]
In screen 50 you can see the effect of reducing the slew factor. At a factor of around 50 the curve becomes less sinuous, approximating more closely to a mode 1 slew. It will need an increased amount of slew to restore the alignment (arrowed blue).
Sensible values for the slew factor are in the range 5-200.
screen 51: [ ••• ]
Finally a few screens of examples. In screen 51 I have inserted an improvised diamond-crossing into the slewed return curve, using the methods outlined in the diamond-crossing tutorial.
Just to make it more interesting, I arranged it to bridge the start point of the slew. Note that a similarly slewed track is needed for the branch road across the centre, and that its slew start position needs to be approximately co-incident with that in the main road (yellow arrows).
screen 52: [ ••• ]
Then in screen 52 I added a single-slip road. This composite improvised template comprises seven overlaid templates, of which five cross into the return curve and so need to be slewed. Notice that in the case of the left-hand slip switch, this required the template to be swapped end-for-end, and its slew start position then has to be adjusted until the slew end marker (arrowed yellow) coincides with the other start markers.
screen 53: [ ••• ]
Screen 53 shows the same thing without the clutter. The crossing angles are 1:6.5 .
screen 54: [ ••• ]
Then in the final screen 54 I added a few more tracks for fun, and put an additional turnout in the return curve. Not a very likely-looking plan on reflection, but interesting to do!
That completes this tutorial. Thanks for reading this far.
Martin.
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© revised 15-12-00.