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Using the easy-assembly Finetrax pointwork kits in 00 and EM (and in P4 from the S4 Society)


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Thanks Martin, you always get there before me! :)

 

British Finescale is not VAT registered, so there is no VAT charged on the sale.

 

But there maybe import duty's to France, which you seem to be aware of.

 

 

Edited by Wayne Kinney
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@Wayne Kinney If the trackwork falls under the 'toy' category (as are model railways), then no import duty is payable (at the moment), so good news there. On the other hand, I'm not sure that in France there is a threshold as in the UK under which a certain amount of business does not attract VAT.  I think that it is the value of goods passing through customs (regardless of VAT or not UK end) will attract payable VAT here. We shall see!

 

Thanks to @MartinWynne for the radius info. That to me is interesting as the Peco 'large' radius are supposed to be 5', but IIRC someone did a detailed measure of the points and they're not much greater than the medium at 3' in order to maintain the same 12° angle (though longer).

 

4' 3" radius will do me fine especially if they are slightly flexible. Now if you can do the same with the diamonds .......... :good_mini:

 

Cheers,

 

Philip

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18 minutes ago, Philou said:

That to me is interesting as the Peco 'large' radius are supposed to be 5', but IIRC someone did a detailed measure of the points and they're not much greater than the medium at 3' in order to maintain the same 12° angle (though longer).

@Philou

 

Hi Philip,

 

No need to measure anything, it's simple geometry. To achieve a 1" offset to the double-track centre-line, at 12 degrees angle, the radius cannot be larger than 45.76".

 

How Peco manage to describe that as 60" is one of life's many mysteries.

 

R = 1 / ( 1-COS(12) )  applies everywhere, including South Devon. :)

 

Martin.

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As I live in South Devon I have been wondering why Martin keeps referring to our area, as I am sure that we don't claim to be subject to different rules to everyone else round here, and I have just twigged what this is about. For Martin's information, the village of Beer is in the area that is usually described as East Devon, even though said village is on the south coast of the county. You have to be west of the Exe estuary to be in the real South Devon.

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21 minutes ago, CamRys said:

As I live in South Devon I have been wondering why Martin keeps referring to our area, as I am sure that we don't claim to be subject to different rules to everyone else round here, and I have just twigged what this is about. For Martin's information, the village of Beer is in the area that is usually described as East Devon, even though said village is on the south coast of the county. You have to be west of the Exe estuary to be in the real South Devon.

 

Thanks. Every day is a school day. :)

 

 https://www.openstreetmap.org/relation/2114883#map=11/50.8291/-3.3282

 

Martin.

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8 hours ago, martin_wynne said:

 

Thanks. Every day is a school day. :)

 

 https://www.openstreetmap.org/relation/2114883#map=11/50.8291/-3.3282

 

Martin.

 Hi Matin,

 

I do enjoy it when you get the maths out ......... R = 1 / ( 1-COS(12) ), I bet I haven't seen that for fifty years;-)

 

quick edit, I had to punch the numbers into a calculator to see if it worked ... happy days!

 

Ian

Edited by Ian_H
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On 07/11/2021 at 19:15, martin_wynne said:

@Philou

 

Hi Philip,

 

No need to measure anything, it's simple geometry. To achieve a 1" offset to the double-track centre-line, at 12 degrees angle, the radius cannot be larger than 45.76".

 

How Peco manage to describe that as 60" is one of life's many mysteries.

 

R = 1 / ( 1-COS(12) )  applies everywhere, including South Devon. :)

 

Martin.

Hi Martin

That's interesting  

Is it some kind of average radius based on what seems to be a transition curve rather than a tangential curve between the switch rail and the crossing (which I think for Peco large radius turnouts is about 10 deg.)?  However, the nominal 36" radius of other turnouts such as SMP's isn't much more convincing. I think the habit of quoting model railway pointwork as radii rather than crossing angles must have come out of the habits of the tinplate world where curves were (and are for Setrack) tangential. It is interesting to compare the quoted radii of Peco's 83 line turnouts defined by frog number (as the NMRA have always done) with those for Streamline.

Something I have been wondering about is how much difference the Anglo American PW practice of basing the crossing number on an equilateral triangle rather than the tangent of a right angle triangle makes at these large crossing angles. It means that you can't just derive the equivalent crossing number of say a Tan 0.13 crossing by taking the reciprocal but what, for example, does a 12deg. crossing angle (Peco Streamline small and medium) equate to as a crossing angle?

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5 hours ago, Pacific231G said:

Hi Martin

That's interesting  

Is it some kind of average radius based on what seems to be a transition curve rather than a tangential curve between the switch rail and the crossing (which I think for Peco large radius turnouts is about 10 deg.)?  However, the nominal 36" radius of other turnouts such as SMP's isn't much more convincing. I think the habit of quoting model railway pointwork as radii rather than crossing angles must have come out of the habits of the tinplate world where curves were (and are for Setrack) tangential. It is interesting to compare the quoted radii of Peco's 83 line turnouts defined by frog number (as the NMRA have always done) with those for Streamline.

Something I have been wondering about is how much difference the Anglo American PW practice of basing the crossing number on an equilateral triangle rather than the tangent of a right angle triangle makes at these large crossing angles. It means that you can't just derive the equivalent crossing number of say a Tan 0.13 crossing by taking the reciprocal but what, for example, does a 12deg. crossing angle (Peco Streamline small and medium) equate to as a crossing angle?

Great looking points....but call me old school....left or right...small  medium or large! Far easier.....what happens between the point blades and a inch or so the other side of frog is all irrelevant for a kit as some one done the hard work....if it looks right....if it runs right...it will do for me!...and prob most modellers.....don't need to know the ...cos..sign...r+23...common uncommon or off on a tangent.

You don't see all that guff on a pack of peco points

Just get ya finger out of the frog and get the 14.2mm points out!

Great points looking points....hope I can put together well to do them justice ..thanks for effort to produce and work the maths out for us simple foke.

Don't forget it's a train set.....

G

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On 09/11/2021 at 17:51, bradfordbuffer said:

Great looking points....but call me old school....left or right...small  medium or large! Far easier.....what happens between the point blades and a inch or so the other side of frog is all irrelevant for a kit as some one done the hard work....if it looks right....if it runs right...it will do for me!...and prob most modellers.....don't need to know the ...cos..sign...r+23...common uncommon or off on a tangent.

You don't see all that guff on a pack of peco points

Just get ya finger out of the frog and get the 14.2mm points out!

Great points looking points....hope I can put together well to do them justice ..thanks for effort to produce and work the maths out for us simple foke.

Don't forget it's a train set.....

G

Fine but I'm afraid it doesn't answer my question about crossing angle calculations and I do have a good reason that's relevant to me for asking about it.

The trouble is that a single turnout may look alright and even the longest wheelbase stock may run over it quite happily but, in trying to cram a quart into a pint pot -as most of us are- which means using far sharper pointwork than the big railway, the effect on things like buffer locking over crossovers (real or apparent) does become important.  Peco's large radius points appear fairly generous (I don't have the length for them)  but use two of them as a crossover and the improvement between that and a pair of their medium radius points is not as great as we might expect (mainly I think because they are curved beyond the frog/crossing to get the same 12 degree angle so, on a crossover,  you get a continuous S curve) . Some of us have the skills to produce complex pointwork tailored to the location but most of us rely on standard items -whether kits or RTL- and here,  small differences in geometry do seem to make a significant difference. 

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I'm not sure if this was specifically stated upthread but a 12 degree crossing is 1:4.7 in old money. Although this is commonly quoted as the angle used by Peco for their 00 Streamline range, measuring up on the template for the long crossing reveals that the angle is in fact closer to 1:4.9 or 11.5 degrees.

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8 hours ago, Pacific231G said:

in trying to cram a quart into a pint pot -as most of us are- which means using far sharper pointwork than the big railway, the effect on things like buffer locking over crossovers (real or apparent) does become important........

.....but most of us rely on standard items -whether kits or RTL- and here,  small differences in geometry do seem to make a significant difference. 

 

Totally agree,

 

In my case I was really struggling to get viable solutions with PECO streamline using Anyrail as my planning tool. It was all about the curves. When the BF products came along those small differences in geometry which I could suddenly achieve were a revelation.

 

I had been put off working in Templot for various reasons but once I bit the bullet and set myself to understanding how it works, using its very basic elements allowed me to solve all those quart into pint size problems. As Martin Wynne said many pages ago of the BF turnouts, "really a game changer". You're not kiddin' mate.

 

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On 11/11/2021 at 09:04, Compound2632 said:

I'm not sure if this was specifically stated upthread but a 12 degree crossing is 1:4.7 in old money. Although this is commonly quoted as the angle used by Peco for their 00 Streamline range, measuring up on the template for the long crossing reveals that the angle is in fact closer to 1:4.9 or 11.5 degrees.

It is if you use the simple tangent of 11.5 degrees but , as I understand it., British and American PW practice is to base the crossing number on an isosceles triangle  (which can of course be seen as two right angle triangles back to back) that's mathematically slightly more complicated but apparently easier to mark out on the ground. It's not a huge difference but, calculated that way, a 1:5 crossing angle comes out as 11.4 degrees which suggests that Peco actually based their geometry on  a no. 5 crossing.  They do have a #5 turnout in their code 83 American line so it would be interesting to compare the geometry of that.  By comparison, I make the crossing angle of an SMP 3 ft radius point to be  about 10 degrees.  or about no.5.5 but an original "3ft radius" Pecoway point appears to have an almost identical geometry to a modern Streamline medium. 

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3 hours ago, Pacific231G said:

It is if you use the simple tangent of 11.5 degrees

 

I can't work out if there is a question here?

 

Peco geometry uses 12 degrees -- from the web site:

 

peco_long_xing.png.2e5a5b60a1349a3be42d963b128d385b.png

 

 

12 degrees is 1:4.70 RAM and 1.4.76 CLM:

 

peco_exit_angle.png.de9c59dd81cc9bd216c24c6046751b4a.png

 

 

RAM = Right Angle Measure = Templot default and some Continental European prototypes:

 

ram_angle_diagram.png


RAM unit angles are traditionally used by modellers because they correspond with normal engineering practice and are easily set out with dividers -- all measurements are either along the rail or at right-angles to it. Templot uses RAM angles by default for this reason.


CLM = Centre Line Measure = most US and UK prototypes:

 

clm_angle_diagram.png

 

Measurements are made along an imaginary centre-line between the vee rails, and at right angles to that centre-line. Neither measurement is along the rail. It's easy to do on the ground with gauging tools which fit across the rails, but more difficult on a drawing board. CLM unit angles are used because the rules-of-thumb formulae which are used by the p.w. gang when setting out pointwork on the ground are simplified, and produce closer approximations to the true mathematical result.

 

Nowadays with everything done on computers there is no real need for unit angles, we could work directly in degrees or radians. But tradition dies hard and the unit numbers are brain-friendly and easy to remember.

 

cheers,

 

Martin.

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43 minutes ago, martin_wynne said:

I can't work out if there is a question here?

 

Peco geometry uses 12 degrees -- from the web site:

 

Measurement of SL-194 long crossing confirms that the crossing angle is tan-1 (26.0 mm / 248.5 mm) = 11.5 degrees:

 

Scan_20211112.jpg.911c1027d76b15d3ebeb39bff7fd4170.jpg

 

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You don't need to do maths to measure the crossing angle from a Peco template.

 

Just draw a line along one rail, and a line along the other and measure the angle between them.

image.png.e0eee746a6ffbd5962a4c29b3aec8cd0.png

A decent drawing program will tell you the angle between two lines. Answer: 12°

 

(Note that the older Peco templates use photographs of the actual product and so are subject to a bit of distortion and some small differences from mathematical perfection whereas newer ones are computer-generated direct from the CAD.)

 

Edited by Harlequin
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5 hours ago, martin_wynne said:

 

I can't work out if there is a question here?

 

Peco geometry uses 12 degrees -- from the web site:

 

12 degrees is 1:4.70 RAM and 1.4.76 CLM:

RAM = Right Angle Measure = Templot default and some Continental European prototypes:

RAM unit angles are traditionally used by modellers because they correspond with normal engineering practice and are easily set out with dividers -- all measurements are either along the rail or at right-angles to it. Templot uses RAM angles by default for this reason.


CLM = Centre Line Measure = most US and UK prototypes:

Measurements are made along an imaginary centre-line between the vee rails, and at right angles to that centre-line. Neither measurement is along the rail. It's easy to do on the ground with gauging tools which fit across the rails, but more difficult on a drawing board. CLM unit angles are used because the rules-of-thumb formulae which are used by the p.w. gang when setting out pointwork on the ground are simplified, and produce closer approximations to the true mathematical result.

 

Nowadays with everything done on computers there is no real need for unit angles, we could work directly in degrees or radians. But tradition dies hard and the unit numbers are brain-friendly and easy to remember.

 

 

cheers,

 

Martin.

Thanks Martin, (though, even more traditionally, most modellers in Britain seem to have used radii rather than crossing angles) 

 

I've measured for myself a scan of three nominally three foot radius points. The Streamline medium and a fairly ancient Pecoway examples (with apparently identical geometry) did indeed come out as 12 degrees. The SMP scaleway example is 10 degrees. Slightly curiously, the lead of the SMP turnout is, despite the shallower crossing angle, a bit shorter  than the two from Peco.

 

BTW I don't know about practice in the rest of continental Europe but SNCF expresses its crossing angles as tangents (tan 0.13, tan 0.10 etc.) though some of the former companies used degrees.  I've been trying to equate these with UK/US crossing/frog numbers hence my interest in any significant difference between RAM and  CLM (as I now know they're called.

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3 hours ago, Harlequin said:

You don't need to do maths to measure the crossing angle from a Peco template.

 

Just draw a line along one rail, and a line along the other and measure the angle between them.

image.png.e0eee746a6ffbd5962a4c29b3aec8cd0.png

A decent drawing program will tell you the angle between two lines. Answer: 12°

 

(Note that the older Peco templates use photographs of the actual product and so are subject to a bit of distortion and some small differences from mathematical perfection whereas newer ones are computer-generated direct from the CAD.)

 

Hi Harlequin

What graphics package are you using? I have PSP and that doesn't measure line angles (or if it does I've not found it yet) and that would be useful.

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2 hours ago, mogman1969 said:

just a quick note to Wayne , having read thru and studied the photographs of your kits i must say they look truly the mutts nuts . 

ease of constuct and a very reasonable price are winners !

are outside slips on your radar ?

 

Just don't ask what angle! 

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8 hours ago, Pacific231G said:

Hi Harlequin

What graphics package are you using? I have PSP and that doesn't measure line angles (or if it does I've not found it yet) and that would be useful.

 

Xara Designer Pro+ (I'm on the development team).

 

9 hours ago, Compound2632 said:

Interesting! What is the angular resolution of your drawing program?

 

The coordinates of the endpoints are stored as large integers. For instance, one line is from (64032, 407585) to (534725, 458571)

The angle of the line is calculated in double floating point radians by finding the arc tangent of the offset between those points. (And then again for the other line and subtract or rotate both lines so that one is horizontal.)

 

All very accurate up to this point but then the answer is converted to degrees and rounded to 2dp to show it to the user in a friendly format. The answer I got from the UI was in fact 12.01° but since 0.01 degrees makes no real difference to the discussion and could be down to me not quite lining things up accurately I reported it as 12.

 

You did ask! :smile_mini2:

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19 minutes ago, Harlequin said:

Xara Designer Pro+ (I'm on the development team).

 

 

The coordinates of the endpoints are stored as large integers. For instance, one line is from (64032, 407585) to (534725, 458571)

The angle of the line is calculated in double floating point radians by finding the arc tangent of the offset between those points.

 

All very accurate up to this point but then the answer is converted to degrees and rounded to 2dp to show it to the user in a friendly format. The answer I got from the UI was in fact 12.01° but since 0.01 degrees makes no real difference to the discussion and could be down to me not quite lining things up accurately I reported it as 12.

 

Youi did ask! :smile_mini2:

 

Thanks. I'm a CorelDraw user - doesn't have that facility (at least in the version I have) so have to rotate a line and do he maths - which, on the same template as I was drawing lines on before, gave me +6.1 and -5.9 so 12.0 degrees with a resolution of 0.1.

 

I concede!

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