Fast Tracks

Hi,
just a question about exact angle of the above mentioned crossings: are they true 14 and 19 degrees, or are they #8 and #6 angles multiplied by two (then, respectively, 14.3053? and 19.0546)?

I have tried to understand by checking on the whole site, but with no success.

Consequent question: if they are true round angles, which are the reasons to build such crossings?

Thank you all

I converted the pdf's to dxf and imported them into 3rd planit. My crossings came out at 14.2456 and 19.0090 degrees

Hi,

The 14 and 19 degree crossings are half the angle of #6 and #8 turnouts. These are designed to be used for crossovers or where two facing turnouts diverge on the same side with the diverging routes crossing each other.

_________________
Cheers!

Tim Warris
Fast Tracks
http://www.fast-tracks.net
service@fast-tracks.net

Thank you all.
Dan have you performed the same conversion for curved turnouts too? I am still getting crazy in understanding the curved turnout geometry, since every source I have found states different values, so far!

You might find this piece that Tim wrote a few years back interesting. May give you some insight as to why you are having trouble pinning down the geometry of curved turnouts.

http://www.handlaidtrack.com/forums/vie ... ght=curved

_________________
Cheers!

Ron Warris
Fast Tracks

... the origins from a straight turnout lead to remember that in NMRA turnout standards there is a sort of "skew" in the diverging route beginning (2.01 degrees for turnouts up to #6, if I remember properly).

The combination of the "skew" and the post I have addressed to Dan has opened my mind however, and by using his curved turnouts as a template, I AM REBUILDING RIGHT NOW FAST TRACK CURVED TURNOUTS EXACTLY BY SIMPLY ADJUSTING THE 3RD PLANIT TURNOUT PARAMETERS!!!!!

I hate to use other people's words but... it's a small step for a man, but a big one for mankind!

Stay tuned for the library completion!!!

See this thread for my 3pi library.

http://www.handlaidtrack.com/forums/viewtopic.php?t=761

3pi only represents curved turnouts as arcs. The work that I did shows that the inside radius is more of a spline shape. You could tweak 3pi objects to get an approximation of the shape, but it won't be very acccurate. I converted the pdf files into dxf files. Imported the dxf file into 3rdplanit. Then I drew 4 points on the outside arc and 4 additional points on the inside arc. I exported these point dimensions out of 3rdplanit into a csv file. I used a program called labview to do a spline interpolation along both curved turnout paths using the imported point values. Labview creates a csv file of points that I import back into 3pi. There are some developmental parts of 3pi that are only available to the beta group. One of these is scripting. 3pi can read the csv file of points and draw the lines automatically. This same setup also works for straight turnouts and wyes.

My objects are not functional turnouts inside 3pi. They are short little line segments connected together. You can drive trains over them inside 3pi.

3pi also has an offset curved turnout that lets you adjust the entry to intersection. Download the 3pi manual from the website. It has some info inside that details the turnout parameter values.

Hi all,
here is my first attempt to build a Curved Turnout library by using only 3rd Planit parameters; some further adjustement to parameters will be necessary, but even now the approximation is fine, IMHO.

Next refinement will be to have end of rails at a 1 inch track spacing, a very time consuming activity based on trial and error.

I have to thank Dan, as previously stated, for his library who has allowed me, by overlapping my turnouts on his ones, to verify the correctness of the achieved shapes.

Pls try it and give some feedback, in order to keep improving.

Sorry, my first attempt to attach files seems to have reached no success...