Turnout construction - Question here please.

Discuss the prototype and how to model it.
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Julian Roberts
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Re: Turnout construction - Question here please.

Postby Julian Roberts » Sun Dec 13, 2020 9:38 am

Hi Tony
Many thanks for the latest instalment on diamonds and slips.

One thing I didn't understand is how to use a check rail gauge when adjusting the fit of the first point rail.

Adjusting the fit of the first point rail using the wrong gauge. The check rail gauge should really be used but this is easier when making the initial fit.

SS9 Adjusting initial fit of point rail using wrong gauge.jpg



(The actual photo doesn't copy over to this)

Do you have any advice on the filed tip of the point rail - should it be slightly rounded as with a crossing V?

The other thing I'd like to ask is about the S4/P4 difference, as you model in S4. I'm not sure you've said this on the thread, could you confirm that a 1:8 is the flattest angle allowed on the prototype and thus in S4, because of the unchecked length? What is the flattest in P4 to give the same safety margin? Similarly, the table of curving diamonds must be slightly more restrictive in P4?

Lastly, ideally could that table of curves include a conversion to scale mm (or perhaps a link to John Donnelly's conversion thingy which was on the Forum recently?)

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Re: Turnout construction - Question here please.

Postby Tony Wilkins » Mon Dec 14, 2020 9:17 am

Hi Julian.
I will come back to you on this if I may as there are several questions here and I need to think about some of them.
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Tony.
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Re: Turnout construction - Question here please.

Postby Julian Roberts » Tue Dec 15, 2020 11:31 am

Hi Tony
No problem, thanks for giving some time to consider. I don't subscribe to the modern expectation that we give instant responses in this age of electronic communications ;)

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Re: Turnout construction - Question here please.

Postby Tony Wilkins » Tue Dec 15, 2020 1:56 pm

Julian Roberts wrote:Hi Tony
Many thanks for the latest instalment on diamonds and slips.

One thing I didn't understand is how to use a check rail gauge when adjusting the fit of the first point rail.

Adjusting the fit of the first point rail using the wrong gauge. The check rail gauge should really be used but this is easier when making the initial fit.

SS9 Adjusting initial fit of point rail using wrong gauge.jpg



(The actual photo doesn't copy over to this)

No, I can never get them to copy over either.
If one thinks about how a Check rail gauge is intended to be used to measure the distance between the check face of a rail and the running face of the opposite rail, it becomes apparent that in this situation there is no rail to measure it from. Hence my comment about using the Crossing Flangeway gauge to help temporarily set the first point rails. I fully expect further adjustments to be required in the alignment of the point rails, indeed the likelihood of getting them spot on first go is rather small.

Do you have any advice on the filed tip of the point rail - should it be slightly rounded as with a crossing V?

I make the Obtuse Crossing point rails the same way as I do for Acute crossing point rails except that for certain circumstances I make the end of the nose thinner than normal to help reduce the unchecked distance. I tend to make the obtuse check bends sharper than they should be for the same reason.

The other thing I'd like to ask is about the S4/P4 difference, as you model in S4. I'm not sure you've said this on the thread, could you confirm that a 1:8 is the flattest angle allowed on the prototype and thus in S4, because of the unchecked length? What is the flattest in P4 to give the same safety margin? Similarly, the table of curving diamonds must be slightly more restrictive in P4?


This is an interesting question and the one I really had to think about.
Yes my own track is all built to S4 standards, but the same methods described are generally related to P4 standards.
Obtuse crossings are perhaps the situation where the difference can make itself most felt.
You are correct in as much as 1:8 fixed obtuse crossings are the flattest that are allowed on the prototype, flatter angles being of the switched type only, but that is only a partial answer as the situations is complicated where curves are concerned as already discussed.
Since S4 dimensions mirror the prototype, there is no reason why S4 track should perform any differently to the full size in any given situation.
The same cannot be said of P4 track however.
The S4 flangeways are 0.58mm and for the maths assuming a sharp end to the fine point, for a 1:8 obtuse crossing, the gap will be 0.58 X 8 = 4.64mm.
For P4 flangeways at 0.68mm the corresponding gap will be 5.44mm. To reduce this gap to 4.64mm requires a crossing angle of 1:6.82, so even a 1:7 crossing does not give the same level of security in P4 as a 1:8 does in S4.
This result was greater than I expected before I did the sums.
Lastly, ideally could that table of curves include a conversion to scale mm (or perhaps a link to John Donnelly's conversion thingy which was on the Forum recently?)


Not sure I can help with a link but I will see what I can do with the my construction thread.
EDIT: 4mm equivalents now added.
Regards
Tony.
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Re: Turnout construction - Question here please.

Postby grovenor-2685 » Tue Dec 15, 2020 3:43 pm

There is a lot of misconception about the non use of a crossing flangeway gauge for checkrail gaps.
The standards are such that, with nominal guage track the crossing flangeway and check rail flangeway are equal and hence the CF gauge can be used for both. Which is what the prototype does when fixing the check rail to the stockrail with standard spacer blocks to give 45 mm flangeway. The need to gauge from the opposite rail only applies where there is gauge widening. Making straight diamonds there should be no gauge widening so the CF gauge should be correct for all 4 point rails and as mentioned its very difficult to use a check gauge at that location anyway. When making curved diamonds of a small enough radius to need gauge widening then you are in a different ball game and quite a bit of trial and error may be needed to get reliable running but it can be done.
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Martin Wynne
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Re: Turnout construction - Question here please.

Postby Martin Wynne » Tue Dec 15, 2020 4:56 pm

grovenor-2685 wrote:Which is what the prototype does when fixing the check rail to the stockrail with standard spacer blocks

Indeed, but when drilling and fixing the check rail chair to the timber, it is the check rail which is gauged from the opposite rail, not the stock rail.

In effect what this means is that yes, it is ok to use the CF gauge to set the check rail gap, but only if you fix the check rail first and use the CF gauge to set the stock rail from it.

In practice it is not that simple, but for an ordinary turnout quite a few model track builders like to fix the turnout-side check rail first (using the check gauge from the V-crossing), before adding the turnout-side stock rail.

If you do it the other way and use the CF gauge to set the check rail, you need to be sure that the stock rail is set exactly to gauge, otherwise you will be compounding any errors.

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Re: Turnout construction - Question here please.

Postby Martin Wynne » Tue Dec 15, 2020 5:27 pm

Tony Wilkins wrote:You are correct in as much as 1:8 fixed obtuse crossings are the flattest that are allowed on the prototype, flatter angles being of the switched type only, but that is only a partial answer as the situations is complicated where curves are concerned as already discussed.
Since S4 dimensions mirror the prototype, there is no reason why S4 track should perform any differently to the full size in any given situation.
The same cannot be said of P4 track however.

There are 2 ways to improve the checking at fixed K-crossings:

1. use a deeper wheel flange.

2. raise the check rail above the level of the running rails, as is done nowadays on the prototype.

When the originators of P4 decided to increase the flangeway gap by 17%, they could usefully have made a corresponding increase in the flange depth to allow for the situation at K-crossings. They didn't, but that still leaves the option of raising the check rail, for example by using code 100 flat-bottom rail with the foot filed off.


Image

Image

Shows only the wheel flange, rest of wheel omitted. More words and music about these diagrams at:

https://85a.co.uk/forum/view_topic.php? ... d=6#p31536

N.B.

a. do not use raised check rails with locomotives having flangeless driving wheels. This is now causing route restrictions for some preserved locomotives running on Network Rail.

b. in the case of slips, the ends of raised check rails will need to be cut down where it is possible for the outer edge of a wheel running on the slip road to catch against them. This is sometimes done on the prototype even with normal check rails, to allow for future wear of the slip rail.

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Re: Turnout construction - Question here please.

Postby grovenor-2685 » Tue Dec 15, 2020 7:43 pm

Martin Wynne wrote:
grovenor-2685 wrote:Which is what the prototype does when fixing the check rail to the stockrail with standard spacer blocks

Indeed, but when drilling and fixing the check rail chair to the timber, it is the check rail which is gauged from the opposite rail, not the stock rail.

Have you seen that done Martin? I've not seen P-way men with other than a standard track gauge that only measures beteen running edges. Why would they use a different gauge when the one they have gives identical results?

There are 2 ways to improve the checking at fixed K-crossings:

1. use a deeper wheel flange. etc.

But is this a real problem that needs addressing? Diamonds have not been problematic in my experience.
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Re: Turnout construction - Question here please.

Postby Martin Wynne » Tue Dec 15, 2020 8:14 pm

grovenor-2685 wrote:Have you seen that done Martin? I've not seen P-way men with other than a standard track gauge that only measures between running edges. Why would they use a different gauge when the one they have gives identical results?

Hi Keith,

Not with my own eyes, no. I will try to find the reference in the track maintenance manuals. Bear in mind that some check chairs are designed to provide gauge-widening, usually available in three different widths. Those chairs can't be fixed or checked with a standard track gauge bar. The only way is with a check gauge bar.

There are 2 ways to improve the checking at fixed K-crossings:
1. use a deeper wheel flange. etc.

But is this a real problem that needs addressing? Diamonds have not been problematic in my experience.

I didn't say it needed addressing necessarily, I was simply responding to Julian's questions. But some folks do have problems with diamonds, especially when built on a curve.

The prototype obviously thinks it needs addressing, now that some cast K-crossings are made with raised check rails.

cheers,

Martin.
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Re: Turnout construction - Question here please.

Postby grovenor-2685 » Tue Dec 15, 2020 8:23 pm

Martin Wynne wrote: Bear in mind that some check chairs are designed to provide gauge-widening, usually available in three different widths. Those chairs can't be fixed or checked with a standard track gauge bar. The only way is with a check gauge bar.
cheers,
Martin.

But then you choose the check chairs according to the gauge widening and hence set the running rail to that figure, track gauges are usually adjustable or can use spacers so can still be used. In reality gauge widening in S&C is rare, the special chairs are mostly for continuous check rails on curves.
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Re: Turnout construction - Question here please.

Postby Julian Roberts » Wed Dec 16, 2020 1:18 pm

Hi Tony

Thank you and Martin for all this helpful material.

grovenor-2685 wrote:But is this a real problem that needs addressing? Diamonds have not been problematic in my experience.


A friend who has exhibited his P4 layout many times didn't know his wagons could go the wrong way on his 1 in 8 slip till I asked him the other day to see if they would. They never have done in practice. But from the above it is clear that on the P4 model we rely on perfect alignment between 8 and 7 (6.82 to be exact), which is what I wanted to know for sure. Unless we take measures such as Martin has suggested.

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Re: Turnout construction - Question here please.

Postby Tony Wilkins » Wed Dec 16, 2020 2:44 pm

Julian Roberts wrote:Hi Tony

Thank you and Martin for all this helpful material.

grovenor-2685 wrote:But is this a real problem that needs addressing? Diamonds have not been problematic in my experience.


A friend who has exhibited his P4 layout many times didn't know his wagons could go the wrong way on his 1 in 8 slip till I asked him the other day to see if they would. They never have done in practice. But from the above it is clear that on the P4 model we rely on perfect alignment between 8 and 7 (6.82 to be exact), which is what I wanted to know for sure. Unless we take measures such as Martin has suggested.


Hi Julian.
I don't know that you can necessarily draw such a hard and fast conclusion as that from the figures I quoted. What my statement inferred was hypothetically comparing a 1:8 S4 obtuse crossing to one with a similar degree of checking using P4 standards. The other major variable (as has already been mentioned) is the size of the wheel and its corresponding flange length below rail level. Obviously the smaller the wheel the shorter the flange length available for checking and guidance. Therefore wagon and similar sized wheels are likely to be the first to reach a potentially critical situation. But it is difficult to work out when exactly that would be reached as there are so many variables that could impact the result. It could be derived empirically I suppose but just because one wheel set behaves in a particular way does not necessarily mean that they they all would.

I think though you are correct that often we rely on the wheel sets continuing in a straight line over the critical areas of trackwork without realising it. I have had experience of rolling stock behaving in situations where perhaps it shouldn't. The situation gets worse with the wider flangeways used in other standards.
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Re: Turnout construction - Question here please.

Postby davebradwell » Wed Dec 16, 2020 4:37 pm

For a long time I've felt that securing Jackson couplings to the opposite end of the vehicle can contribute to problems at crossings and elsewhere, particularly with longish or poor running trains and now use a pulling post behind the nearest axle as in MRJ 223. I suppose propelling round curved diamonds would be another difficult move as contact on a single buffer will impart a turning moment trying to push the vehicle down the wrong road.

Can't say I'd be comfortable knowing a vehicle could go down the wrong hole. It seems a bad place to start.

DaveB

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Re: Turnout construction - Question here please.

Postby Tony Wilkins » Wed Dec 16, 2020 8:37 pm

davebradwell wrote:For a long time I've felt that securing Jackson couplings to the opposite end of the vehicle can contribute to problems at crossings and elsewhere.
DaveB

Hi Dave.
I have often thought the same in spite of using them that way and for that reason try to attach the wire on the center line of the wagon if possible. The acid test will be when I can run really long trains on Brimsdown.
At the risk of going off at a tangent.
It came as something of a suprise to discover that full size wagons used a similar system with the coupling hooks at each end being linked by a long rod with a spring arrangement in the center taking all the draw gear forces thus effectively towing each wagon along by the rear coupling plate. I presume this was done to reduce the internal forces applied to wooden underframes as the practice was largely discontinued with steel underframed wagons.

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Re: Turnout construction - Question here please.

Postby davebradwell » Wed Dec 16, 2020 9:07 pm

At least the prototype arrangement guided the hook at the front so there was a tendency to pull towards the track centre. With Jacksons installed by the book and no front guide it's an unstable arrangement, especially on curves where the couplings follow the chord. Sorry for deviation but I was pointing out the existence of devilish forces trying to make a vehicle go the wrong way.

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Re: Turnout construction - Question here please.

Postby Julian Roberts » Thu Dec 17, 2020 12:50 pm

I haven't had those wagon problems nor any other on my very short test trains (just one buffer in contact) on my trial curved diamond even with a very heavy load - does the length of a train make a difference I wonder?

Having been thinking about obtuse crossings the last three weeks, I've just one more poser, which comes in this drawing

SRE42L 1 in 7.5 Obtuse Crossing.JPG


What stands out to me is 1. the curve at the middle on the knuckle of both the stock rails and check rails. Surely this will decrease the checked length? So why is that OK on the prototype - don't the same issues apply? and 2. do I detect a shaping of the point rails so that their ends are not actually on the gauge line, nor the check line? I've exaggerated this here - this is looking at the right point rail in the previous drawing:

Shape of point rail.jpg


The top drawing is what I have been trying to do, shortened till there is enough strength, the lower is what the prototype drawing might be showing? If so, that is the opposite of what Iain Rice suggests here, and which I've borne in mind.
20201217_120948.jpg


Obviously in 4mm scale the difference would be minute, but perhaps worth bearing in mind, as we're talking about a few thou here and there making the difference in P4.

Going back to the knuckle and stock rail curve, I surmise that the jarring that might occur with a sharper bend would be more detrimental to the route of the wheel than the possible decrease in checked length...?
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Last edited by Julian Roberts on Thu Dec 17, 2020 2:49 pm, edited 1 time in total.

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Martin Wynne
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Re: Turnout construction - Question here please.

Postby Martin Wynne » Thu Dec 17, 2020 1:25 pm

Hi Julian,

The knuckle bend radius in the K-crossing rails (and at the wing rail knuckle in V-crossings) serves the same purpose as the flared end on a check rail.

So that a wheel back coming under control of the check rail does so progressively as it first makes contact.

Likewise the front of a wheel flange running against the rail head can progressively make contact with the wing rail (the running rail) after crossing the flangeway gap.

There is a drawing showing the machining of K-crossing point rails in the NERA reprint book. I will get it scanned later and post it.

For the best running, always take a few thou off the top of the nose of crossing vees and point rails to allow for the coning angle on the wheels as they run along the wing rail. And round over the filed running edge to match the the top corner 1/2" radius on the rail section.

cheers,

Martin.
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Re: Turnout construction - Question here please.

Postby David Thorpe » Sat Dec 19, 2020 7:19 pm

Isn't all this ply and rivet construction just a bit old hat now? Surely most people are using Exactoscale or C&L chairs and sticking them directly to the sleepers and I'd certainly like to see a bit more about how that is done, including the positioning of chairs in the more awkward areas and ensuring there is no gauge widening. For those that are using ply and rivet, I assume that you are then having to apply cosmetic chairs and I'd be interested to know how you go about that. I've found it something of a nightmare as the holes in the base of Exactoscale chairs are just a little bit smaller than the head of the rivet in the sleeper which means that in order to get a close fit of the chair it is necesary to file away some of its base. Doing that for all the chairs - or more accurately all the half chairs -in a turnout is an extreme pain, especially when a rivet is not directly under the rail or ones soldering is not as minimal as might be hoped.

I cannot help but think that anyone contemplating starting out in P4 who then reads this page will gain the imoression that trackwork construction in P4 is exceptionally complicated and will start thinking about EM instead, especially now that Wayne Kinney's new point kits are to become available. I was rather disappointed to see the negative attitude shown on this forum towards these and their possible application to P4.

DT

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Re: Turnout construction - Question here please.

Postby Terry Bendall » Sat Dec 19, 2020 8:21 pm

David Thorpe wrote:Isn't all this ply and rivet construction just a bit old hat now?


Well it has been around for a long time David but it still has its place. I have in the past used a mix of riveted sleepers and functional chairs successfully but that method can cause problems with expansion and I have used about 8 Exatoscale turnout kits on two different layouts. I have also built some Colin Craig kits for turnouts using flat bottom rail. I have just built a fairly complicate set up of two tandem turnouts and two plain turnouts which form two crossovers with two sidings off and used ply and rivet since it was for me the easiest way of doing things. and the advantage is that when adjustments have to be made simply heating the soldered joints allows this to be done. With glued functional chairs that is far more difficult.

Once everything has been tested I shall fit cosmetic chairs and my plan is to grind off any rivets that are visible either side of the rails, cut the chairs in half, trim to fit and then glue. I have done this successfully before so I know it works. Tedious but there is not a lot to do.

David Thorpe wrote:gain the imoression that trackwork construction in P4 is exceptionally complicated and will start thinking about EM instead,


I don't think the construction is any more complicated in P4 compared to EM, but because the tolerances are a bit tighter you just need to be a bit more careful how things are done.

Terry Bendall

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Re: Turnout construction - Question here please.

Postby davebradwell » Sat Dec 19, 2020 8:31 pm

You're completely ignoring the Masokits etched chairs which Julian has just used successfully - these must be the best way to make soldered pointwork.

I recall that the negative comments about potential new point kits was genuine concern over whether the technique could meet the P4 tolerances and given his existing commitments, whether they could be made available in a reasonable timeframe.

The abundance of information we have now seems to drown out the basics of this subject occasionally but there's nothing to stop anybody from using the good old 60's technique of just soldering rail to sleepers cut from pc board should they wish - we have to choose our own level of complexity.

DaveB

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Re: Turnout construction - Question here please.

Postby barhamd » Sat Dec 19, 2020 10:15 pm

Terry Bendall wrote:I don't think the construction is any more complicated in P4 compared to EM, but because the tolerances are a bit tighter you just need to be a bit more careful how things are done.

Terry Bendall


I'd completely agree with Terry, I've built both EM and P4 trackwork and it is next to identical, you just use different size jigs and need to be a little more careful of the tolerances using the P4 jigs as it is a little less forgiving. I used ply sleepers and exactoscale chairs on my model of Clare, I don't bother with rivets at all, just use a bit of scrap etch under the rails of the crossing. Dare I say it but the new Peco bullhead functional fishplates are actually quite good and can be used in P4.

David

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Re: Turnout construction - Question here please.

Postby David Thorpe » Sat Dec 19, 2020 10:19 pm

I haven't used Masokits chairs bacause I don't use PCB sleepers, and never have. I've always thought that timber sleepers are visually more appealing. So for many years I used ply and rivet and tried to pretend that the little blobs of solder on each rivet represented a chair. At the same time, it struck me as completely daft that when I took such care to get the track gauge looking as good as possible my "chairs" were less convincing that those on most proprietary RTR systems. Oh, there were cosmetic chairs available but as I recall they were expensive and difficult to fit.

So then along came the plastic functional chairs from Exactoscale and C&L.. Terrific, I thought, and adopted them for my new layout with pretty disastrous results as I hadn't realised, far less allowed for, the fact that when I set the gauge using the standard society gauges I'd always used, the chairs subsequently started to cant in which led to gauge narrowing and unsatisfactory running. I also tried adapting the chairs to fit some of my old ply and rivet pointwork, which had remained true to gauge, but the whole procedure was absurdly tedious although the end result was largely satisfactory.

I'm now thinking of building some hybrid turnouts, with a few strategically placed rivets, but otherwise using Exactoscale chairs slid onto the rail beforehand. These would not have to be cut in half and fitted retrospectively. But will this too lead to problems? The rivets hold the rail vertically, the chairs want to cant inwards. The rivets are stronger then the chairs and I hope that the rail would therefore remain upright throughout the turnout, but am a bit concerned lest the chairs would continue to try to turn the rail inwards. Just how strong is their cant?

So perhaps that shows why I think that any tutorial on building pointwork in 2020 should really concentrate on functional chairs!

As for Wayne's new point kits, it seemed to be taken for granted that they would not meet P4 tolerances. Excatoscale used to produce point kits that presumaby met P4 tolerances (provided you knew about and made allowance for the cant) and C&L still do (same proviso), so I'm not quite sure why Wayne Kinney wouldn't be able to. I do understand however that as things stand it might not be worth his while financially to give it a try.

And as for the complications of P4 trackwork, just put yourself in the position of someone considering moving to P4 and then try reading this thread from TEXBEDZ's posting downwards..... As others have said (and I completely concur) it really isn't complicated so why try to make it seem so?

DT

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Re: Turnout construction - Question here please.

Postby allanferguson » Sat Dec 19, 2020 11:23 pm

David Thorpe wrote:Isn't all this ply and rivet construction just a bit old hat now? Surely most people are using Exactoscale or C&L chairs and sticking them directly to the sleepers and I'd certainly like to see a bit more about how that is done, including the positioning of chairs in the more awkward areas and ensuring there is no gauge widening. For those that are using ply and rivet, I assume that you are then having to apply cosmetic chairs and I'd be interested to know how you go about that. I've found it something of a nightmare as the holes in the base of Exactoscale chairs are just a little bit smaller than the head of the rivet in the sleeper which means that in order to get a close fit of the chair it is necesary to file away some of its base. Doing that for all the chairs - or more accurately all the half chairs -in a turnout is an extreme pain, especially when a rivet is not directly under the rail or ones soldering is not as minimal as might be hoped.

I cannot help but think that anyone contemplating starting out in P4 who then reads this page will gain the imoression that trackwork construction in P4 is exceptionally complicated and will start thinking about EM instead, especially now that Wayne Kinney's new point kits are to become available. I was rather disappointed to see the negative attitude shown on this forum towards these and their possible application to P4.

DT


I must agree with the general sentiment. I have used plastic chairs with ply sleepers for some years and find them very reliable. The chairs need to be threaded onto the rails before laying them, and for point and crossing work the order of doing this needs a bit of thought. The actual crossing I assemble offscene using a jig and all four rails are soldered to a wee piece of brass sheet of a thickness to raise them off the sleepers by the same amount as the chairs. The piece of brass is cut back to the width of the chairs and is undetectable after cosmetic half chairs are added The only other place I solder is slide chairs where this is the only way to keep the stock rail attached -- I use brass slide chairs.
One issue I've never resolved is gauge widening, which I need "round the ends". There is no track gauge I know of which will give controlled gauge widening. I got round it by using widened gauge track bases from exactoscale, but these are not entirely satisfactory -- for one thing 8'6" sleepers are not correct for my pregroup layout.
Trackwork construction in P4 is complicated; but so it is in EM and 00 also; and anyone who can build locomotives and rolling stock in P4 can certainly build track.

Allan F

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Re: Turnout construction - Question here please.

Postby Philip Hall » Sun Dec 20, 2020 12:36 am

My visible turnouts are likely to be the hybrid variety as David describes but with one difference: the plastic chairs will not be threaded onto the rail but cut in half and added later along with those that conceal the rivets. With ply and rivet every three sleepers the rail will be held firmly, and the intermediate chairs, glued each side of the rail, will not try to force the rail off vertical but will still hold it firm. I can’t tell/am not bothered if the rail is vertical.

That’s the theory anyway. All off stage track is to be soldered PCB.

Philip

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Re: Turnout construction - Question here please.

Postby Highpeak » Sun Dec 20, 2020 2:15 am

I think "old hat" is a somewhat weighted term for a method or process that as Terry Bendall observes still has a place as a one of several viable means of building track. As far as I can see there are some advantages to the process and some drawbacks, but I think this could be said of other approaches too.

From the perspective of a beginner any of the soldered construction techniques offer the significant advantage of adjustability. I had to do quite a bit of "adjusting" of the track on my shunting plank once I bought a Mint gauge which most obligingly showed me the error of my fortunately not completely permanent way. I had to adjust some of the track that used the plastic components along with the ply and rivet work and while the plastic fittings can be persuaded to come loose and be moved slightly the process is not quite as straightforward as a quick dab with a soldering iron.

David does have a valid point about the addition of cosmetic chairs which can be a time consuming process, especially if rivet placement wasn't completely accurate. Overall I think the cosmetic steps (including painting) probably take me as long as the construction phase itself. Painting though must surely be part of any track construction method.

The first two turnouts I built gave me a self-awarded C- "Must take more care" grade. They were built prior to Tony's thread which encouraged me to have another go, and the results of applying most of his methods led to a significant improvement in the outcome. The Mint gauge slides through the turnout built after reading Tony's thread quite smoothly.

Lacking any sort of rivet press I just used the vise jaws to close the rivet, a bit time consuming but it did the job. I also deviated from the process by using a needle in a pin chuck to mark out the rivet locations as I found I got more accurate results. It's not my idea but I can't remember where I read it. Bill Bedford's etched brass components for slide chairs also came in handy but a lesson learned there was to move the rivet location so that the edge of the slide chair didn't stick out a long way from the rail which made adding the plastic cosmetic chair harder than it needed to be.

One thing that the traditional ply and rivet method shares with other approaches is the satisfaction that comes from building something and making it work. Tony's thread is invaluable as far as this method is concerned. Having greatly enjoyed the virtual Scaleforum presentations, in particular David Brandreth's work on resistance soldering, I think there is a place for a well-produced video version of Tony's thread as a real aid for beginners. Other methods would probably also benefit from this, video being a powerful instructional tool when it's done well.
Neville
If at first you don't succeed, try reading the instructions.


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