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TEMPLOT 3D PLUG TRACK - To get up to speed with this experimental project click here.   To watch an introductory video click here.   See the User Guide at Bexhill West.

  • The Plug Track functions are experimental and still being developed. Some of the earlier pages of this topic are now out-of-date.

    For an updated overview of this project see this topic.   For some practical modelling aspects of using Plug Track see Building 3D Track.

    The assumption is that you have your own machines on which to experiment, or helpful friends with machines. Please do not send Templot files to commercial laser cutting or 3D printing firms while this project is still experimental, because the results are unpredictable and possibly wasteful.

    Some pages of this and other topics include contributions from members who are creating and posting their own CAD designs for 3D printing and laser-cutting. Do not confuse them with Templot's own exported CAD files. All files derived from Templot are © Martin Wynne.
  • The Plug Track functions are experimental and still being developed.

    For an updated overview of this project see this topic.   For some practical modelling aspects of using Plug Track see Building 3D Track.

    The assumption is that you have your own machines on which to experiment, or helpful friends with machines. Please do not send Templot files to commercial laser cutting or 3D printing firms while this project is still experimental, because the results are unpredictable and possibly wasteful.

    Some pages of this and other topics include contributions from members who are creating and posting their own CAD designs for 3D printing and laser-cutting. Do not confuse them with Templot's own exported CAD files. All files derived from Templot are © Martin Wynne.

Curved or tangent centre lines

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Frank

Member
Location
Netherlands
Hello - I am pretty new to templot and trying to find out my way in how to work with. One of the issues I have is that when I generate a turnout I always have a curved centre line in the middle of the TS. See the figure below:

Turnout_curved_centre_line.JPG


I see from examples that generating a tangent line in the TS of a turnout is possible:

Turnout_tangent_centre_line_topic2522.JPG


My question is how can I do this and how to calculate the length (and angle) of this tangent line piece?
Thanks in advance!

Frank
 
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@Frank

Hi Frank,

Welcome to Templot Club. :)

Screenshots showing the TS (turnout-side) centre-line as a straight line are from older versions of Templot. In later versions of Templot the TS centre-line follows the centre path of the TS rails.

I changed it so that the dummy vehicle tool can roll along the TS side of a template when checking running clearance.

In all the years I have been using Templot I never found any use for the straight line, so I'm a bit puzzled why you need it? It was only ever intended as a means to identify the position of the deflection point (DP).

It's very rare that you need the deflection point (it's not meaningful for curviform V-crossings, and for regular and generic V-crossings it is only of much use if the template is straight).

But you can still use the deflection point if you wish -- click this menu item to put the peg on it:


peg_on_dp.png



If you click that menu item repeatedly, the peg will toggle between alignment with the main road (MS) and alignment with the turnout road (TS):


peg_on_dp_1.png



With the peg aligned to the TS, it takes only a couple of clicks to put the notch under it, and then peg on a length of straight track:


peg_on_dp_3.png


(Or more usually, a couple of dabs on the keyboard -- the Divide and Multiply keys are on the keyboard number-pad, / and *.)

With this result:

peg_on_dp_2.png



The angle matches the current angle set for the V-crossing -- it is shown on your screenshot:


frank_angle.png



It is 1:4.7 RAM. For those Peco templates that is 12 degrees exactly.

To find the length, simply shorten the plain track template (F4 mouse action) until it aligns with the end of the rails, and read off the length (this is not a Peco template, the angle here is 1:6 RAM):


plain_track_length.png



I hope this answers your question, although it's many years since I have had any reason to do this. Such a straight track can be more easily pegged onto any of the other TS peg positions through the V-crossing with a single click:


peg_on_ts_side.png



Or using the SHIFT & JOIN button a template can be quickly aligned to the TS exit without needing any other clicks.

Perhaps you can say a bit more about why you need to use the deflection point?

cheers,

Martin.
 
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message ref: 6651
@Frank

p.s. Frank,

It is still possible to see the straight centre-line if you convert the turnout to a half-diamond template:

peg_on_dp_4.png


This assumes you are starting with a regular or generic V-crossing, to create a regular half-diamond.

cheers,

Martin.
 
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message ref: 6652
Hi Martin,

Many thanks for your extensive explanation!

In the past I used German software tooling (Spur-0-MEC / S21) for turnout design and used the "Tangenten"/Deflection Point to easy calculate the size of a turnout on a calculator by hand. Also I compared measurements with drawings on paper of old german railroad turnouts. The figures in these old drawings are often w.r.t. the Deflection Point. That's why I was used to work in this way. Besides that, as beginner in Templot, I was not aware I could do this by means of PEG/Notch settings. You are right that in most cases it has only value for individual turnouts with straight MS.
Thanks!

Frank
 
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message ref: 6654
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