Steps for laying a 3-way turnout

[Lacathedrale]

Hello all,

 

I've still yet to build a three-way turnout and I think, save for conjoined formations it is really the last hurdle for me in track building to overcome before being free to pick and choose my track layouts.

 

For ease of discussion, I've labelled up a Peco 3-way with colours to illustrate the components:

 

 

My understanding is that the pink vee/wing assembly is the most crucial, since a flat edge pressed against outside faces will locate and determine so much of the rest of the turnout. When it comes to the order of construction however, I'm a little bit at a loss! It would appear that everything needs to come together simultaneously!

 

If anyone could spare the time to tell me which order to build in, I'd be very appreciative!

 

Thank you,

[martin_wynne]

Hi William,

 

If you get everyone to agree on a sequence it will be a miracle.

 

I would start with the upper purple stock rail, taking care to get the set angle correct and properly aligned over the template.

 

Then add the red vee, gauged from the stock rail and a straight edge from the switch front. Then add the light green wing/closure (in two pieces, it will need an isolating gap).

 

You will then have a base from which everything else can be gauged.

 

The pink wing/closure will need a gap in it, and each part can be fixed separately for gauging: pink vee, blue vee, light blue stock rail from them, pink wing rail from stock rail.

 

It's a good idea to decide on all the isolation gaps before you start. The red and pink vees don't need a gap between them, they can be polarity-switched in one piece on the first switch. The blue vee is polarity-switched on the second switch.

 

cheers,

 

Martin.

[Lacathedrale]

I'd not considered the gapping of the pink rail, which makes things alot more easy to manage - it requires only one bend in the pink vee rail to bring it around to the check rail position against the red vee, rather than two at precise points.

 

I guess one could lay the red vee, purple rail either way around (I normally start with a straight stock rail then the vee in normal turnouts) ?

 

Gapping wise, I'm assuming this:

 

 

I'll be using PCB sleepers with etched chairs, so gapping can be done post-hoc but the rail cuts really need to be done ahead of time.

 

 

[martin_wynne]

Hi William,

 

What are the gaps at the end of the stock rails for? (ringed violet):

 

 

At the green ring, you will have a tricky gap in the copper-clad between the orange/pink rails. I would move the pink gap one timber to the left.

 

At the blue rings it would be better to stagger the gaps by a couple of timbers to increase the strength of the finished item -- unless you are fitting prototypical plastic fishplates.

[Lacathedrale]

Violet - Not for any particular reason other than to delineate things for which the turnout is not concerned

For Blue/Green - thank you for the tips. I'm going to be laying the actual pointwork out in Templot at a much more shallow angle so I wasn't focusing on  specific joint locations, rather how they would be gapped in relation to each other.

 

I think we are of an accord, and it's about time to break out the soldering iron!

[ianb3174]

This was my most recent attempt at one, in EM-SF. Started by fabricating all the crossing V's and assembling into common crossing assemblies using a society jig. Once they were in location relative to each other I added the stock rails etc. 

[Lacathedrale]

ah, so you've gone with a fully plain vee for both, the kink being a separate wing rail...

[ianb3174]

Yes. I didn't do myself any favours with the design. It was a pig to get right but despite looking rough it works as well as anything else I've built. Is only a fiddle yard after all (yes, I practice trackbuilding on the unseen bits too).

As you might know from other threads of mine this whole thing may be rebuilt in S scale at a later stage. Waits for years to build stuff with jigs and then chooses to move to a scale where they don't exist yet. 

[martin_wynne]

Hi William,

 

Is this a photo of an actual Peco production tandem turnout?

 

If so, I've just noticed that there is a check rail missing (yellow):

 

 

I imagine Peco have fixed it by now, because otherwise folks must surely have been reporting derailments? Is the other hand version the same?

 

Perhaps it is just a published template from a pre-production item?

 

cheers,

 

Martin.

[hayfield]

On 14/09/2020 at 21:39, ianb3174 said:

This was my most recent attempt at one, in EM-SF. Started by fabricating all the crossing V's and assembling into common crossing assemblies using a society jig. Once they were in location relative to each other I added the stock rails etc. 

 

 

Ian

 

I totally agree with you on this one, build the 3 common crossings first as sub assemblies, I then find the center line of the turnout fitting the Pink subassembly first then adding the third common crossing. Do be careful with the center road to get the gauge correct. 

 

I accept many like fitting a stock rail first, I must be cack-handed as whenever I try this method I end up with a lop sided turnout

 

By the way a nice bit of track laying