Turnout construction - Question here please.

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

Postby Tony Wilkins » Sat Feb 17, 2018 2:38 pm

Julian Roberts wrote:Do I understand correctly that on the switchblades, you say the horizontal profile is a straight line from the tip to the stockgauge, the full length of the planing, rising from the 0.25mm below rail level at the tip?.

For this type of switch, which is semi-curved, Yes. The important thing is to produce an even taper over the length of the planing. (Better for it to be slightly hollow rather than convex).

My experience with switches is that if the blades are less than full height after a certain point of their length, a wheel can tend not to take the direction of the switch, particularly the diverging route. However at the tip (as you have shown) it does need to be below rail level or there will be gauge narrowing, as (surely?) it's not possible to file rail to less than about 0.2 thickness, which on a B switch will be approx 7mm from the tip - so my horizontal taper has been from there to the tip, made naturally by the filing.

I have just measured one of my switch blades at the tip with a micrometer and the rail thickness is 0.2mm, however this is at a point about half way down the rail height as there is a vertical taper to the rail above this, which is maintained for at least half the length of the planing.
Here is a diagram of an undercut switch showing the section at the toe or tip of the blade. Obviously we cannot hope to produce such a section and the reality is that the back of our switch blades will be flat as per the vertical line down the middle of the switch blade. The important thing to note though is the chamfer to the top edge of the running face. This is pretty much the last operation described in making the switch blade.
Switches006.JPG
Switches006.JPG (14.7 KiB) Viewed 3782 times

The idea of this chamfer is to deflect the flange and guide it away from the stock rail. It will continue to do this for some distance as the head of the switch blade rises until the tread of the wheel makes contact with it. The reason for the set leading the switch tip is to allow some clearance for the thickness of the switch blade as well as matching the angle of deflection.

At your half way point, say 15mm, the rail top is theoretically c.0.1mm below the stock rail if I get you right. Clearly these are almost just numbers but I would be worried about any encouragement of our P4 wheels not to take the right course.


If the head of the switch blade were flat then yes it could well pick up the flange and cause a derailment, but it isn't. (See above).

Going to the crossing, while your knuckle is directly on a timber I have seen turnouts where the knuckle is between two timbers, and this is the case on Martin Wynne's post of a Templot crossing in your Brimsdown thread.

If the knuckle is between two timbers it would be much easier to see the place where the bend should be once the timbers are stuck down onto the template.
Prototype practice varied, I take it?


Where the knuckle bend occurs depends purely on the angle of the crossing and the width of the crossing flangeway. As the angle changes, the distance from the blunt nose to the knuckle bend will change also. As the timber centres are at fixed spacings they will inevitably clash at some settings.

I must say I would be happier (with my third hand) to use a ruler to be sure to exactly align the running route of first knuckle/wing rail with the V as well as using the drawing, as (maybe it's my eyesight) I would not be sure I had the exact vertical perspective.


Having soldered the first two joints for the wing rail and checked the alignment with the rule, I was not satisfied with it, it is a simple matter to unsolder the wing rail and shift it forward or back a small amount as required and try again.
Regards
Tony.

Julian Roberts
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Re: Turnout construction - Question here please.

Postby Julian Roberts » Sat Feb 17, 2018 3:13 pm

Martin Wynne wrote:
A P4 turnout cannot be an exact scale model of a prototype turnout for this reason. For that you need to use S4.



Thanks Martin. P4 is good enough for me and I'm committed with stock that can't be altered without a lot of work, and want the interoperability on P4 layouts not having one of my own so far - but I do admire Tony's trackwork in dead scale, and I wonder if working to S4 would be not as difficult as is thought.

Thanks also for the clarification about sleeper spacing being constant and thus the knuckle can vary in its correct place from to the right, to straight over, to the left, of that X timber.

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Martin Wynne
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Re: Turnout construction - Question here please.

Postby Martin Wynne » Sat Feb 17, 2018 3:30 pm

Hi Julian,

Here are some pics of an undercut switch. You can see from the shiny marks on the top of the blade that it starts to take some part of the wheel load at about the position of the second stretcher bar. Up until that point it is simply guiding the wheel flange, and is dull on top:


undercut_dull_top1.jpg
undercut_dull_top1.jpg (135.11 KiB) Viewed 3781 times


undercut_dull_top2.jpg
undercut_dull_top2.jpg (137.89 KiB) Viewed 3781 times

You can see that the tip is very thin, and if continued up to the top of the stock rail it would indeed be a knife edge.

The way to model this is to do the final shaping with fine abrasive paper (wet-or-dry paper from car shops), with the blade clamped against the stock rail.

Notice also a seldom-modelled but quite prominent feature, the steel sole plate on the toe timber. It is used to hold the toe to gauge, so that the stretcher drive and detection rods can be accurately set. Usually there are strips welded on the ends of the sole plate to bear against the chair bases (just visible under the muck on the lower pic), or the ends of the plate are turned up as a forging for the same purpose. In the photos there is an insulated joint in the sole plate because this track is track-circuited.

cheers,

Martin.
40 years developing Templot. And counting ...

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Martin Wynne
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Re: Turnout construction - Question here please.

Postby Martin Wynne » Sat Feb 17, 2018 3:58 pm

Tony Wilkins wrote:What I find interesting is that the questions thread has had more views than the subject thread itself

Hi Tony,

The number of views is directly related to the number of posts, and largely meaningless.

Every time there is a new post, the same people view the topic again, clocking up the number of views.

If you want more views to show on your build thread, break it into smaller posts. It will show a lot more views, but that won't indicate any difference in the level of interest.

cheers,

Martin.
40 years developing Templot. And counting ...

Tony Wilkins
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Re: Turnout construction - Question here please.

Postby Tony Wilkins » Sat Feb 17, 2018 5:14 pm

Martin Wynne wrote:A P4 turnout cannot be an exact scale model of a prototype turnout for this reason. For that you need to use S4.


One of the perhaps stranger aspects of this occurs with obtuse crossings in S4-X, where I have to choose "timbering as model" to get the timbering correct for exact scale track. The reason why is obvious with a little thought. P4 modellers are going to constitute by far the majority of users, so this has to be the default setting. I would have done the same, were I designing Templot, but I do find it amusing sometimes. It is therefore up to the mavericks like me to adjust things to suit themselves.
Regards
Tony.

Tony Wilkins
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Re: Turnout construction - Question here please.

Postby Tony Wilkins » Sat Feb 17, 2018 5:20 pm

Martin Wynne wrote:
Tony Wilkins wrote:What I find interesting is that the questions thread has had more views than the subject thread itself

Hi Tony,

The number of views is directly related to the number of posts, and largely meaningless.

Every time there is a new post, the same people view the topic again, clocking up the number of views.

If you want more views to show on your build thread, break it into smaller posts. It will show a lot more views, but that won't indicate any difference in the level of interest.

cheers,

Martin.

Thanks for the explanation.
My comment was more an observation than anything else.
I am well aware that some of the views will be me every time I log in to add another section.
I have no intention of trying to bias the system!
Regards
Tony.

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Martin Wynne
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Re: Turnout construction - Question here please.

Postby Martin Wynne » Sat Feb 17, 2018 5:21 pm

Tony Wilkins wrote:
Martin Wynne wrote:One of the perhaps stranger aspects of this occurs with obtuse crossings in S4-X, where I have to choose "timbering as model" to get the timbering correct for exact scale track.

Hi Tony,

If that's the case it is a bug. The "as prototype" option should be exactly that. Just checking it now.

Martin.
40 years developing Templot. And counting ...

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Martin Wynne
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Re: Turnout construction - Question here please.

Postby Martin Wynne » Sat Feb 17, 2018 6:01 pm

Copied from the Templot web site:
_________________________________

Image These notes apply to UK-pattern bullhead track only.

Setting the Curved Stock Rail :

The diagram below shows the position of the set (bend) in the turnout-side (TS) stock rail, which matches the planing angle on the switch blades and is needed to ensure a correct track gauge through the turnout road of the switch. Templot puts a mark across the curved stock rail at the position of the set, as shown below (for a left-hand switch).

Image

In Templot the set is slightly in advance of the tip of the opposite blade, as shown, and in order to ensure that the geometry works correctly the TP peg position (CTRL-2) is in advance of the blade tip by half this amount.

The diagram shows the set mark at the minimum amount of set advance. There is no harm in having a little more in models to help protect the mating blade tip from wheel damage. However, an excessive set advance should be avoided as this can cause a knock to the wheels of trailing traffic. Often for facing traffic, and on all GWR switches, the set is replaced with a joggle.

Undercut Switch Blades :

The first diagram below shows the left-hand stock rail and switch blade for a left-hand undercut pattern switch with a plain unjoggled stock rail. This is the type of blade planing most often modelled because it requires only a plain set in one stock rail.

A set (bend) is put in the turnout-side (TS) stock rail at the toe of the switch (blade tip) to match the planing angle on the switch blade.

The switch blade is planed (machined) to a sharp tip, and profiled down below the top of the stock rail to fit under the head of the stock rail (undercut). This is in order to have sufficient strength at the tip.

Such a blade acts only as a guide to the wheel flanges for the first part of its length and does not actually support the weight of wheels running onto it until they have reached some way along it. Undercut switches can often be identified in photographs because the shiny top of the open blade stops some way short of the tip.

Image

Image

Image

Here are some photos of an undercut switch. You can see from the shiny marks on the top of the blade that it starts to take some part of the wheel load at about the position of the second stretcher bar. Up until that point it is simply guiding the wheel flange, and is dull on top:

Image

Image

You can see that the tip is very thin, and if continued up to the top of the stock rail it would be a knife edge.

The way to model this is to do the final shaping with fine abrasive paper ("Wet-or-Dry" paper from car shops), with the blade clamped against the stock rail.

Notice also a seldom-modelled but quite prominent feature, the steel sole plate on the toe timber. It is used to hold the toe to gauge, so that the stretcher drive and detection rods can be accurately set. Usually there are strips welded on the ends of the sole plate to bear against the chair bases (just visible under the muck on the lower photo), or the ends of the plate are turned up as a forging for the same purpose. In the photos there is an insulated joint in the sole plate because this track is track-circuited.

Straightcut Switch Blades with Joggled Stock Rails :

When a more robust switch is needed, both of the switch stock rails are joggled outwards by a small amount to create a housing for the switch blade tips and so protect them from wheel damage. This next diagram below shows this alternative straightcut pattern switch with a joggled stock rail.

Image

Instead of a plain set in the stock rail at B, it is joggled sideways between positions A and C, with the maximum deflection from its previous unjoggled alignment being at the blade tip position B. In bullhead track the joggled section is always created by bending the rail rather than by machining a notch in it.

The switch blade is planed to a blunt tip (straightcut), to a thickness corresponding to the amount of joggle, which has been exaggerated in this diagram for clarity. Apart from a rounded corner at the tip the blade is the full height of the stock rail and plays its part in supporting the wheels along its full length. A straightcut switch can often be identified in photographs by showing a shiny top on the open blade all the way to the tip.

Image

In defining a joggled switch, two dimensions are needed. The joggle depth (sideways deflection) at B, and the joggle return length in front of the blade tip between positions A and B, in which the rail returns to its normal alignment. (The length between B and C always corresponds to the planing length for the switch blade). These dimensions need to be entered when creating a custom joggled switch in Templot.

Having entered joggle dimensions for your custom switch, you can choose whether to actually use the joggles for an individual template by means of the joggled stock rails option tickbox.

Image

Here is a photo of a GWR joggled switch with straightcut planing. Notice the thicker more robust nature of the blade tip, and that it is full height and shiny all the way to the tip. Notice also that the depth of joggle in the stock rail is very small in relation to the rail width. It is not easy to create such a joggle in models.

Image

Prototype notes:

REA and straight loose-heel switches can be either joggled or not - normally joggled switches are used only in facing positions on running lines. In trailing positions there is a danger of rough running when wheels hit the joggle return length on the open switch blade side, most severely when the main-road is curved. However, all GWR and BR(WR) switches are joggled.

For REA switches the joggle depth is 3/8" (0.375 inches) and the joggle return length is 6 inches. For older pattern straight loose-heel switches these dimensions vary, but are usually similar.
For GWR old-pattern switches the joggle depth is 3/8" (0.375 inches) and the joggle return length is 4 inches. The later GWR and BR(WR) curved flexible switches have a less severe joggle, the joggle depth is 1/4" (0.250 inches) and the joggle return length is 6 inches.

These joggle depths are barely perceptible in the smaller model scales. A 1/4" joggle is only 3 thou (0.003 inches) (0.08 mm) in 4mm/ft scale. Some modellers prefer a more pronounced joggle, and Templot provides for this with the generator > overscale joggles menu option, which creates a joggle depth of 3/4" (scale).

Visitors to the Severn Valley Railway steam heritage line in Kidderminster UK can very easily observe the difference between joggled and unjoggled switches. In platform 1 the engine release turnout at the buffer stops has an REA semi-curved flexible switch with undercut-pattern switch blades (no joggle). In platform 2 the engine release turnout has a GWR curved flexible switch with straightcut-pattern blades and joggled stock rails. The very much more robust nature of the blade tips in the latter case is very evident.
___________________________________

regards,

Martin.
40 years developing Templot. And counting ...


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Martin Wynne
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Re: Turnout construction - Question here please.

Postby Martin Wynne » Sat Feb 17, 2018 7:55 pm

Martin Wynne wrote:
Tony Wilkins wrote:
Martin Wynne wrote:One of the perhaps stranger aspects of this occurs with obtuse crossings in S4-X, where I have to choose "timbering as model" to get the timbering correct for exact scale track.

Hi Tony, If that's the case it is a bug. The "as prototype" option should be exactly that. Just checking it now. Martin.

Hi Tony,

It turns out that we are both wrong. Image

Here 1:8 K-crossings in S4-X:

Image

Templot has got the K2 timber 25" from the centre. With a 5/8" blunt nose on the point rail, it should overlap the centre of the timber by 5". That would put the timber at 24" centres*. So that's wrong in Templot. On the other hand, if you change to the "as model" option the centres reduce to 23", which is equally wrong in the other direction.

Note that you can correct this by clicking the Forward or Backward buttons once (each click moves the timber by 1").

I will get this fixed in Templot, although maybe not for a day or two.

*REA drawing shows 24.1/32" centres.

cheers,

Martin.
40 years developing Templot. And counting ...

Tony Wilkins
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Re: Turnout construction - Question here please.

Postby Tony Wilkins » Sat Feb 17, 2018 8:34 pm

Hi Martin.
I made the assumption that it was the P4 setting of the reason given in my turnout construction thread.
Funny how these things come to light.
Can't win em all.
Thanks for the additional prototype info and pictures by the way.
Regards
Tony.

Tony Wilkins
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Re: Turnout construction - Question here please.

Postby Tony Wilkins » Sat Feb 17, 2018 8:39 pm

Thanks Keith.
Always useful to have these resources highlighted periodically.
Regards
Tony.

Julian Roberts
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Re: Turnout construction - Question here please.

Postby Julian Roberts » Sat Feb 17, 2018 10:05 pm

Thank you Tony for your reply earlier. Between you and Martin a lot has been made even clearer here today. Thanks both.

junctionmad
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Re: Turnout construction - Question here please.

Postby junctionmad » Sun Feb 18, 2018 12:03 pm

My own problems have largely been confined to correctly positioning the knuckle longitudinally n relation to the V point , using either flangeway shims or roller gauges has always resulted in some slop in the final position . I only really solved it when I created CNC machine common crossing jigs from a Jig I saw at the Guild O show.

Dave

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Re: Turnout construction - Question here please.

Postby junctionmad » Sun Feb 18, 2018 12:27 pm

Given the laborious process involving half chairs , I'm interested in how many people remain with the full JBS method of turnout construction, I would have thought by now the vast majority of " new builds" would be functional chairs or perhaps hybrid methods , rather then full on JBS.

Dave

Philip Hall
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Re: Turnout construction - Question here please.

Postby Philip Hall » Sun Feb 18, 2018 2:20 pm

I too was thinking of hybrid methods; functional chairs augmented with rivets at critical places. This was until I read of gauge narrowing in places after a time, caused by riveted construction holding the rail vertical, and functional chairs being inclined at 1:20. So I think that I may use all riveted in the most important locations on the main running lines where trains will travel at speed, but maybe functional chairs or a hybrid in less critical locations. I have an awful lot of C&L components, including miles of plastic sleepers, which were donated to me many years ago, so I do want to use them up!

Philip

Tony Wilkins
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Re: Turnout construction - Question here please.

Postby Tony Wilkins » Sun Feb 18, 2018 3:37 pm

Yes, half chairs are a pain, I will admit to that. I would not expect everyone to adopt my methods in full, the functional chairs having largely replaced the ply and rivet system although it still has its devotees, but the individual sub units still need to be made regardless. I have tried making a Turnout using functional chairs, but the result was not very successful, so I stayed with what I know. I have found that many of the commercial Vees and switch blades still need some attention to bring them up to standard. The aim of the exercise was to show people what they should be aiming for to achieve the best possible outcome by whatever means they choose to employ.
For my own layout, the plan for the scenic track is, initially at least, to use ply and rivet pointwork and functional / flexi track in between. Much of the real main line at that time was done with FB elastic spike fixings ala Colin Craig, (about 12 meters of it will be required) you think JBS track is tedious. The storage sidings will also be a mix of JBS for the pointwork and all the curved plain track, with C&L flexi for the straight track. I have no intention of adding functional chairs to that or staining the sleepers either come to that.
Mixing soldered joints with functional chairs is always going to be a problem unless one is going to have a few functional chairs fitted first to hold the rail at the 1 in 20 angle. This will though mean incorporating the prototypical twists in the switch, wing and vee rails in the appropriate places.
Regards
Tony.

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Martin Wynne
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Re: Turnout construction - Question here please.

Postby Martin Wynne » Sun Feb 18, 2018 4:25 pm

Below copied from the Templot web site.

p.s. last week I noticed disc sanders currently on offer in Lidl at £29.

cheers,

Martin.
_______________________________

It is much easier to file a vee after assembling it. Even easier if you use a disc sander. Here is some stuff I have posted before, showing how a vee can be constructed to any angle matching the template, without needing filing jigs, and finishing with solid metal at the nose.

I have greatly exaggerated the crossing angle for clarity. The rails are shown in cross-section along the rail -- yellow shows the rail head and foot, orange shows the web of the rail:

Image

Make sure you have both rails the right way up. Bullhead rail has the thicker part at the top.

A is a prepared piece of rail with the end bent to the crossing angle, or slightly less. Allow a little extra on the overall length. Then file the end down to the web as shown to become the splice rail.

Make another one of the opposite hand as B, to become the point rail (nose). No need to file the end yet, but file a side notch in it to receive A as shown. The filing does not need to be very accurate.

C is any scrap bit of rail or etched kit waste, soldered on top of the rail for stability while handling. Unsolder or cut it off after installing the vee in the turnout, and then the surplus vee rail ends are trimmed back as required.

Assemble the vee as shown using high-temperature solder because the rail gets hot while sanding. If it gets too hot stop and dip it in a bowl of cold water. Using high-temp solder also reduces the risk of it coming apart later if you are using soldered track construction.

Hold the assembled vee down on the edge of a small block of wood using a penny washer on top and a couple of screws. Stick a bit of printed template on the block as a guide:

Image

Adjust the fulcrum screw until it is a couple of thou higher than the rail. Check that the rail being sanded is held firm.

A penny washer is a large washer with a small hole. They are sold as backing washers for pop-rivets, fixing canvas, etc. If you don't have a penny washer to hand you could drill a hole in an old coin, or use something else.

Turn the vee round on the block to make the second cut.

The result is as shown after making two cuts on the sander. If necessary the bulk of the metal can be quickly removed with a coarse file or metal shears before finishing on the sander.

The end result is an accurately aligned vee comprised of solid rail at the nose. All that then remains is to fettle the running edges at the tip and blunt back the nose to the specified width as shown on the template (0.25mm/10 thou for bullhead in 4mm scale). It's a good idea to take a few thou off the top of the nose so that it dips down slightly below the wing rails. This allows for the coning angle on the wheels as they run off the wing rail onto the nose, producing smoother running. But don't overdo it.

N.B. Wear a mask while sanding and wash hands afterwards. The sandings will contain lead from the solder. Stick Elastoplast or tape on the ends of your fingers beforehand to protect them if they catch on the sanding disc.

Far East-quality disc sanders are available at lowish cost and very useful for many other workshop jobs:

Image

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Julian Roberts
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Re: Turnout construction - Question here please.

Postby Julian Roberts » Tue Feb 20, 2018 6:11 pm

I may be going irrelevantly and totally uninterestingly off piste Tony in that your series is predicated on using a template, most likely generated by Templot. But supposing I want to make a turnout freelance as it were in a similar way that Iain Rice shows in his book. As you and Martin have shown, the knuckle distance from the V varies with the crossing angle so much that it can be either side of, or on, the X crossing timber. Is there a P4 table to show the correct distance for each gradation e.g. 1 in 4, 1 in 5 etc?

Accuracy of construction would depend on the blunt nose being a consistent width (0.25mm?) as that also gets further from the intersection point as the crossing angle reduces...right?

I also wonder if you will show good ways of connecting the actuating mechanism to the blades.

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grovenor-2685
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Re: Turnout construction - Question here please.

Postby grovenor-2685 » Tue Feb 20, 2018 6:22 pm

But supposing I want to make a turnout freelance as it were in a similar way that Iain Rice shows in his book. As you and Martin have shown, the knuckle distance from the V varies with the crossing angle so much that it can be either side of, or on, the X crossing timber. Is there a P4 table to show the correct distance for each gradation e.g. 1 in 4, 1 in 5 etc?

Depends how free lance you want to be. The REA standard designs have crossing timbers spaced at a standard 2'6" then the chairs are designed to suit.
When building the position of the knuckle is automatically established by alignment of the wing rail to the running edge and to the correct crossing flangeway spacing so there is nothing to measure and hence no need of a table. Setting of the wing rails is shown in detail by Tony above or on my website for a slight variation. Using these methods the blunt nose has no effect.
Regards

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Martin Wynne
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Re: Turnout construction - Question here please.

Postby Martin Wynne » Tue Feb 20, 2018 6:28 pm

Julian Roberts wrote:Is there a P4 table to show the correct distance for each gradation e.g. 1 in 4, 1 in 5 etc?

Hi Julian,

You don't need a table. The distance from the FP intersection point to the centre of the knuckle is the flangeway gap multiplied by the crossing angle.

So for a 1:8 turnout in P4, that is 0.67mm x 8 = 5.36mm.

If you want the distance from the blunt nose, add the blunt nose width to the flangeway gap. So for a P4 1:8 bullhead turnout, that becomes 0.67 + 0.25 = 0.92mm. Multiply by 8 = 7.36mm from nose to knuckle.

For S4 change the 0.67 above to 0.58mm.

cheers,

Martin.
40 years developing Templot. And counting ...

Julian Roberts
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Re: Turnout construction - Question here please.

Postby Julian Roberts » Tue Feb 20, 2018 8:24 pm

Stunningly simple Martin! Thanks!
So just another layer - I have thought it might be difficult to accurately measure the V blunt tip, but could be simpler to mark where it is 1mm wide. So the distance from this mark to the knuckle centre, on say a 1 in 12 angle, would be 1.67 x 12 = 20(.04)mm, correct?

BTW, what does FP stand for?

Thanks Keith also. Very freelance...e.g. fiddle yard perhaps

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grovenor-2685
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Re: Turnout construction - Question here please.

Postby grovenor-2685 » Tue Feb 20, 2018 8:59 pm

BTW, what does FP stand for?

"Fine Point" ie where the gauge lines actually intersect, where the nose would be if it was not blunt.
Shown by the small red cross on Templot prints, as here Image
Regards

Julian Roberts
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Re: Turnout construction - Question here please.

Postby Julian Roberts » Tue Feb 20, 2018 9:52 pm

Cheers Keith

Tony Wilkins
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Re: Turnout construction - Question here please.

Postby Tony Wilkins » Thu Feb 22, 2018 5:20 pm

Julian Roberts wrote:I may be going irrelevantly and totally uninterestingly off piste Tony in that your series is predicated on using a template, most likely generated by Templot. But supposing I want to make a turnout freelance as it were in a similar way that Iain Rice shows in his book. As you and Martin have shown, the knuckle distance from the V varies with the crossing angle so much that it can be either side of, or on, the X crossing timber. Is there a P4 table to show the correct distance for each gradation e.g. 1 in 4, 1 in 5 etc?

Accuracy of construction would depend on the blunt nose being a consistent width (0.25mm?) as that also gets further from the intersection point as the crossing angle reduces...right?

I also wonder if you will show good ways of connecting the actuating mechanism to the blades.


Hi Julian.
I think most of your questions have already been answered by Keith and Martin.
I would say that not having the Ian Rice book you are referring to makes it difficult to know exactly what you are meaning, but I presume hand drawn templates. I have done this for specials in the past (pre Templot) and some of the pointwork on Green Street was done that way. Most though followed the REA standards as that was my reference source. The rest were P4 templates from Studiolith or adaptations thereof. The layout was planned using the quarter scale versions.
The width of the blunt nose is not that critical other than for placement of the vee on the A timber, it will just mean that the wing rails will move to suit, to maintain the correct relationship between them and the vee. As Martin has already explained, the knuckle distance is a product of the Flangeway gap and the crossing angle from the Fine Point.
Turnout actuating mechanisms will be something that I cover eventually when I get that far. I still have some baseboards to make and all the underlay and track to lay first. It is highly likely that the scenic and storage yard turnouts will not be operated the same way either. Some decisions have yet to be made, but my solutions are hardly likely to be anything revolutionary or earth shattering.
Regards
Tony.


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