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A Steamed Elder
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Hi Rod,

Aristo-craft stainless steel ones (USA track) are available in the UK according to Bachmann UK web site. Ref. No. is A20345.

Whoever your UK dealer is could get it. Shipping from the States would probably make the UK price fairly reasonable. Brass is not in stock it seems.
 

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I think you went the wrong way.. A #6 is the same as a #3..


Interesting comments - not sure who's right. This came up before, and didn't get resolved.

As the # is the frog divergence angle expressed as a gradient (e.g. 1 in 6), then a #6 Y shouldn't be any different in angle from a #6 ordinary. Unless the railroad engineers count a Y as having a double-angled frog.

Gotta go check those PRR drawings...

OK. According to the PRR, a #6 frog has an angle of 9 deg 31'. So a #6 Y should be the same - and therefore the curve at the points will be half the curve of a #6 with a straight bit.
 

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A Picture tells a thousand words...or so it is said. In this case two.




The turnouts leading into the Wye are #6 units. The Wye is a #3 Note that the three lines after the wye turnout are parallel.

The article was in Model Railroad News
May 2004 By John Sipple
 

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are #6 units. The Wye is a #3


Yep, that confirms my feeling that it is the frog angle alone that determines what # we call it. On Grant's pic, the curves are all consistent (same radius) but the frog angle is double that of the adjacent straight switches.
 

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A gradient is expressed as rise over length, a right angle type of measurement.
Frogs are of an isosceles type of measurement; two equal sides plus a base. Converting to a gradient measuring scheme is quite complex as the length of a gradient is comparable to the height of an isosceles triangle.
If you consider a wye switch as a 3-way switch minus the straight through track, it's not surprising the frog number is one half of either the left or right turnout.
The angle of the crossing in a scissors crossover is similar to the wye frog: Twice the degree of any one of the four switches or half the frog number of any of the switches.
Math Rules the World
Art
 

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Posted By Schlosser on 07/23/2008 6:31 PM
A gradient is expressed as rise over length, a right angle type of measurement.
Frogs are of an isosceles type of measurement; two equal sides plus a base. Converting to a gradient measuring scheme is quite complex as the length of a gradient is comparable to the height of an isosceles triangle.
If you consider a wye switch as a 3-way switch minus the straight through track, it's not surprising the frog number is one half of either the left or right turnout.
The angle of the crossing in a scissors crossover is similar to the wye frog: Twice the degree of any one of the four switches or half the frog number of any of the switches.
Math Rules the World
Art


Well, it seems that when you try to edit a post, strange things happen. Spaces between lines disappear and sometimes you get double posting with no chance to delete the duplicate. Oh well, live and learn; except I seem to be missing the LEARN part.
 
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