Track is all interconnected - where to start?

[Lacathedrale]

I've finally got the bits enough to start constructing the pointwork for my layout, but I'm having a right mare of a time figuring out where to start. I thought the turnout TL150 in the below diagram would be good, but every rail either ends up as a Vee, or from an existing Vee. I''m not sure my measuring and modelling skills are good enough to have this down perfectly!

 

Where should I start on this? I assumed the crossover highlighted in red would be one unit, the zig-zag platform entry roads another, and the entry crossover and first siding the last - but I didn't expect to have to build them all as one piece! Is there any way around it?

 

[hayfield]

William

 

If I were you I would make the ones in red first as the other two formations are a bit harder.

 

I would start making the 2 common crossings first and concentrate on getting the centre part of the crossover in place then work outwards

[Grovenor]

I would build in the three pieces you suggest.

1. The left hand crossover and the turnout below it.

2. The centre 3 turnouts.

3. The crossover highlighted red.

Two of the joints occur where you have a stock rail abutting very close to an adjacent crossing V.  I would always provide a joint anyway, not try to have a combined v and stockrail. Just shorten the V rail and.or the switch fronts as needed.

Regards

[Lacathedrale]

Cheers guys - I'll try to build as whole units - I'm just a bit nervous

 

How short should I trim close to the vee for that joint? I am worried about things getting kinked. for example, I've soldered up the Vee that would sit under the label PR143 but it looks like it would only be about 3 timbers long before I it starts to overlap with the check rails of TL149

[hayfield]

Make the isolation break the other side of the check rail

[Siberian Snooper]

There should be black cut marks where the prototype would be jointed, I would suggest that you put your cuts in as per prototype.

[Stephen Freeman]

Hi,

I too would build in the 3 sections suggested. If you are worried about providing insulation breaks, remember there are prototype rail joints in the stock rails in the vicinity of the crossing rail joints.

 

Any prototype rail joints in the check rail area can be dummy ones.

 

Where the vee is close to the blades of the turnout to the rear, you could use the same rail joint but it will complicate things electrically so best to shorten the tail of the vee on that rail as Keith says.

[martin_wynne]

Hi William,

 

You are using the turnout road of short turnouts as the running lines, TR102, TR103.

 

When you do that, you need to check that you have adequate running clearance for bogie stock. Assuming these are regular-pattern B-6s in EM at 44.67mm centres, you have a potential conflict:

 

 

 

Using the dummy vehicle tool in Templot (utils menu), you can see that the recommended 6" clearance envelopes are conflicting, leaving less than 6" (2mm) between vehicles if trains happen to pass on this section. With typical models that is not enough to be reliable, allowing for body sway, offset axles, axle sideplay, etc. 

 

That's using the default vehicle dimensions in Templot, which you can change to match your actual stock before testing your track plan.

 

To cure the problem you could use longer turnouts (larger radius), or increase the track spacing on the left, or increase the stagger between the two turnouts (which has the effect of increasing the spacing on the right). The prototype staggers turnouts in double-junctions for the same reason.

 

There is another prototype reason to stagger the turnouts -- so that the stretcher bars are not directly opposite one another, which can create problems for the rodding runs. To that end you need to adjust your stagger in approximately whole timber-space increments.

 

cheers,

 

Martin.

[Lacathedrale]

So I should cut where the marks are around the vee for a gap, except

• where that mark falls by a check rail  I should have it going just past the checkrail
• where the mark falls very close to the tie bar of a turnout, I should cut short

Is that correct?

 

Martin,

 

That's some very interesting info, If I understand correctly while it's incorrect as it pertains to prototypical track formation, surely it's only a factor when I have carriages arranged specifically as you have shown above? i.e. one halfway onto TR103 while another is going through the curved route of TR102?

 

Thanks,

[martin_wynne]

Martin,

 

That's some very interesting info, If I understand correctly while it's incorrect as it pertains to prototypical track formation, surely it's only a factor when I have carriages arranged specifically as you have shown above? i.e. one halfway onto TR103 while another is going through the curved route of TR102?

 

They are both on the curved routes. The condition will arise several times as trains pass one another. For example a train arriving at the same time as one is departing, or while empty stock is being shunted, etc.

 

If you are short of space to use longer turnouts, an alternative way to cure the problem (apart from using wider track centres) would be to introduce some contraflexure into the turnouts, creating a Y-effect, like this:

 

 

Those are the same B-6 turnouts, but you can see that the radius is eased and they look much better. Which also means there is now a much greater clearance:

 

 

cheers,

 

Martin.

[Enterprisingwestern]

Contraflexure.

Word of the day.

Thanks Martin.

 

Mike.

[Lacathedrale]

So the top crossover has been re-printed and I'm about to make a start - however with Martin's suggestion I have re-worked the platform points B8's instead of B6's and it seems to work - the only geometry that seems to affect is the siding (bottom right). I have staggered the crossover at the top of the plan away from the middle formation and that seems to work nicely:

 

Edited November 11, 2018 by Lacathedrale

[martin_wynne]

Hi William,

 

It's difficult to replace a B-6 with a B-8 in the same space without creating misalignments. For example I can see in your screenshot that you have lost the minimum 6ft way between PL184 and TL186.

 

You didn't post your .box file, so I've had a go at recreating it from your earlier screenshots. I'm not sure if this represents your current plan:

 

 

 

I tried replacing your B-6s with B-7.5 curviform, with the middle turnout as B-6.75 regular. Then to fit the available space means building the switches into the back of the V-crossings. Which is doable, but not as easy as conventional plain turnouts. The upper turnout is B-7 curviform.

 

 

As you can see, this has eased the radii and increased the passing clearance by just enough to be workable.

 

But ideally, if you have the space and the baseboard joints permit, it might be better to start again with say B-7 turnouts from scratch, with perhaps 7ft way as the ruling spacing.

 

If you want to take this further please transfer discussion to the Templot Club forum, where others might want to join in, and I will have a look at tidying up the timbering.

 

(click the screenshots to see them full size)

 

cheers,

 

Martin.