selectorBut, R.T., the wye-type turnout does not have a straight component at the frog...which is where we must find one important characteristic to label a given configuration of turnout. For your typical N. American straight, we all know what a #6 should look like. And it does diverge one unit of distance for 6 units of axial travel...at the frog. Not so a wye turnout...it is much steeper because its other side is also diverging. Usually, it is a symmetrical diversion, one mirrored on the other side of the major axis of the turnout. (handlaid ones don't have to be perfectly symmetrical to still count as a "wye"). So, looking down from overhead, we eyeball the turnout as a whole configuration....at the frog. What we see is divergence left at the rate of 1/6 and also right at the rate of 1/6 from the central major axis. Those two diversions, recalling fraction arithmetic, total 2/6, or 1/3, which we call a #3. So, Paul was not meaning to lead you to conclude that he was agreeing with you..at least, that is not how I interpreted his last post. Perhaps I am mistaken, and will gladly be corrected. -Crandell
But, R.T., the wye-type turnout does not have a straight component at the frog...which is where we must find one important characteristic to label a given configuration of turnout. For your typical N. American straight, we all know what a #6 should look like. And it does diverge one unit of distance for 6 units of axial travel...at the frog. Not so a wye turnout...it is much steeper because its other side is also diverging. Usually, it is a symmetrical diversion, one mirrored on the other side of the major axis of the turnout. (handlaid ones don't have to be perfectly symmetrical to still count as a "wye").
So, looking down from overhead, we eyeball the turnout as a whole configuration....at the frog. What we see is divergence left at the rate of 1/6 and also right at the rate of 1/6 from the central major axis. Those two diversions, recalling fraction arithmetic, total 2/6, or 1/3, which we call a #3.
So, Paul was not meaning to lead you to conclude that he was agreeing with you..at least, that is not how I interpreted his last post. Perhaps I am mistaken, and will gladly be corrected.
-Crandell
You are correct. I was attempting to present it a different way to clarify my earlier post. At this point between all of our attempts, I am not sure how to further explain it.
Enjoy
Paul
Why is this so difficult?
From the Railway Engineering Handbook:
"The limiting effects of lead curvatures can be reduced by crotching the frog of a lateral turnout to place 1/2 the frog angle and 1/2 the switch angles to each side of the approach track centerline, thus creating an equilateral turnout."
For the uninitiated, a model railroad wye switch is an equilateral turnout.
Further, the track geometry is correct when you use a wye turnout that is one-half the number of a lateral turnout. That alone should be proof enough.
Since RT used the term equilateral in one of his arguments, he was close in lingo..........we as modelers may have differing views, but the pros know what it is. I think we should take our hints from them.
Do you mean to tell me that Model Railroader, Railroad Model Craftsman, and all the technical journals have been explaining the numbers of turnouts wrong all these 150+ years? In answer to many questions such as, "What's a #6 track switch?" they've been explaining that the number of a turnout is the distance it takes for the frog rails to diverge, measured from the frog point, period. Thus a #6 turnout, straight, curved or whatever, takes six feet for the gauge faces to diverge one foot from the frog point. I repeat: it doesn't matter that one or both rails curve, as it does in Peco turnouts---as very few prototype turnouts actually have curved rails in the frog. Buy a commercial cast or built-up frog and you will see that it's a narrow angle "X." The curvature is in the closure and stock rails a few feet before and after the frog point.
We used to use #4 turnouts, particularly in HO, to save space, but our locos were and are designed to take curves much sharper than the prototypes, particularly steam locos. O scalers who built steam locos to much tighter clearances than those in most locos, usually found that even a #6 could sometimes cause all sorts of flange problems. Somewhere in my MR collection is a whole article devoted to the tightness of model RR curves as opposed to the prototype's. The old standard "Minimum Radius" for HO track was 22 or 24" (sorry, my memory isn't as exact for this as it is for frog dimensions), and when MR reviewed track that dropped below this Minimum Radius, they warned that long cars and anything above six-coupled steam locos might operate on 18 or 20", but would look really ungainly. Unless manufacturers designed larger steam locos that way, they just wouldn't negotiate our sharp curves and low number turnouts. (And some of you may have encountered problems trying to run C-C Diesels on sharp curves and #4 turnouts. It's very frustrating!)
If you don't believe me, put a scale rule up against a commercial turnout's frog at your LHS: if the track turns to the right, left--or both, as in a wye, it'll still take 4' for the frog rails to diverge 1'.)
IRONROOSTER Let me try a different approach. Take a #6 right hand switch and a #6 left hand switch and place the straight tracks over each other so that the diverging legs are opposite each other (similar to a 3 way switch). Ignoring the straight track the diverging legs form a wye which when measured will be 3 units apart for each unit of length, but the angle of each leg from the straight is the angle of a #6. Hope this helps. Paul.
Let me try a different approach. Take a #6 right hand switch and a #6 left hand switch and place the straight tracks over each other so that the diverging legs are opposite each other (similar to a 3 way switch). Ignoring the straight track the diverging legs form a wye which when measured will be 3 units apart for each unit of length, but the angle of each leg from the straight is the angle of a #6.
Hope this helps.
Paul.
This is indeed a heralded day: somebody has agreed with me for a change!
From the far, far reaches of the wild, wild west I am: rtpoteet
R. T. POTEETIRONROOSTER R. T. POTEET Don Z Jim, If you are using a #6 turnout on your layout, the corresponding wye to use would be a #3. Divide the straight turnout frog number by two to get the wye to use with that turnout. #5 turnout = #2.5 wye, etc. Don Z. HUH????? Since each leg of the wye is diverging, each leg is only half the angle of a normal turnout for the same frog number. Thus a #3 wye turnout has each leg diverging at the angle of a #6. Enjoy Paul Your terminology is a little confusing. I don't want to flare up another "How do you measure grade?" controversy but a #6 Wye switch is a switch which has a divergence of one unit in six units; equilaterally--which they do not have to be--is a #3 frog angle--one unit in three--to the right and a #3 frog angle--one unit in three--to the left. The individual instrumental in getting me to tackle scratchbuilding switches in N-Scale pre-Atlas Code 55 has cu N-Scale Code 55 Wye switches using--and this is only an example--a #7 frog to the right and a #3 frog to theleft; this renders and effective #5 frog labeled a #% Wye switch. I've never tried constructing a Wye switch but will probably give it the "old college try" at some time in the future;
IRONROOSTER R. T. POTEET Don Z Jim, If you are using a #6 turnout on your layout, the corresponding wye to use would be a #3. Divide the straight turnout frog number by two to get the wye to use with that turnout. #5 turnout = #2.5 wye, etc. Don Z. HUH????? Since each leg of the wye is diverging, each leg is only half the angle of a normal turnout for the same frog number. Thus a #3 wye turnout has each leg diverging at the angle of a #6. Enjoy Paul
R. T. POTEET Don Z Jim, If you are using a #6 turnout on your layout, the corresponding wye to use would be a #3. Divide the straight turnout frog number by two to get the wye to use with that turnout. #5 turnout = #2.5 wye, etc. Don Z. HUH?????
Don Z Jim, If you are using a #6 turnout on your layout, the corresponding wye to use would be a #3. Divide the straight turnout frog number by two to get the wye to use with that turnout. #5 turnout = #2.5 wye, etc. Don Z.
Jim,
If you are using a #6 turnout on your layout, the corresponding wye to use would be a #3. Divide the straight turnout frog number by two to get the wye to use with that turnout. #5 turnout = #2.5 wye, etc.
Don Z.
HUH?????
Since each leg of the wye is diverging, each leg is only half the angle of a normal turnout for the same frog number. Thus a #3 wye turnout has each leg diverging at the angle of a #6.
Your terminology is a little confusing.
I don't want to flare up another "How do you measure grade?" controversy but a #6 Wye switch is a switch which has a divergence of one unit in six units; equilaterally--which they do not have to be--is a #3 frog angle--one unit in three--to the right and a #3 frog angle--one unit in three--to the left.
The individual instrumental in getting me to tackle scratchbuilding switches in N-Scale pre-Atlas Code 55 has cu N-Scale Code 55 Wye switches using--and this is only an example--a #7 frog to the right and a #3 frog to theleft; this renders and effective #5 frog labeled a #% Wye switch. I've never tried constructing a Wye switch but will probably give it the "old college try" at some time in the future;
R. T. POTEETIRONROOSTER R. T. POTEET Don Z Jim, If you are using a #6 turnout on your layout, the corresponding wye to use would be a #3. Divide the straight turnout frog number by two to get the wye to use with that turnout. #5 turnout = #2.5 wye, etc. Don Z. HUH????? Since each leg of the wye is diverging, each leg is only half the angle of a normal turnout for the same frog number. Thus a #3 wye turnout has each leg diverging at the angle of a #6. Enjoy Paul Your terminology is a little confusing. I don't want to flare up another "How do you measure grade?" controversy but a #6 Wye switch is a switch whhich has a divergence of one unit i six units; equilaterally--which they do not have to be--is a #3 frog angle--one unit in three--to the right and a #3 frog angle--one unit in three--to the left. The individual instrumental in getting me to tackle scratchbuilding switches in N-Scale pre-Atlas Code 55 has cu N-Scale Code 55 Wye switches using--and this is only an example--a #7 frog to the right and a #3 frog to theleft; this renders and effective #5 frog labeled a #% Wye switch. I've never tried constructing a Wye switch but will probably give it the "old college try" at some time in the future;
I don't want to flare up another "How do you measure grade?" controversy but a #6 Wye switch is a switch whhich has a divergence of one unit i six units; equilaterally--which they do not have to be--is a #3 frog angle--one unit in three--to the right and a #3 frog angle--one unit in three--to the left.
Let me try and explain this... Yes, a standard #6 turnout which has one STRAIGHT leg and one ANGLED leg diverges 1 unit for every six units traveled PARALLEL to the STRAIGHT leg. A wye turnout has TWO ANGLED legs. So since each diverges at the same angle AWAY from eachother, the amount of divergence between the two tracks DOUBLES for a given length compared to a normal #6 turnout, as this does the frog number.
Is ther such an animal? YES. It's calles a #3 WYE.
is a #6 wye overkill? YES again. It . takes up a lot of room andf will cost you $45-$75,. plus switch machines
Draw a 10" circle with 3 9" lesgs to aoorximate Atlas' equivalent smallest turnatable, (which only handles Diesels-(no steam)..and takes a whole coner..
A Walthers TT is a much better choice., and all you have to do is to cut a circle inside one of your curves. to fit, and use an auxillary power pak..to run..
Don Z. and Iron Rooster are correct!
A #6 straight turnout has the same radius of curvature are a #3 Wye turnout.
A #5 straight turnout has the same radius of curvature as a #2.5 Wye turnout.
A #4 straight turnout has the same radius of curvature as a #2 Wye turnout
So on and so on.
Don - Specializing in layout DC->DCC conversions
Modeling C&O transition era and steel industries There's Nothing Like Big Steam!
The Atlas CD100 wye is a #3, which matches it's #6 turnouts.
Nick
Take a Ride on the Reading with the: Reading Company Technical & Historical Society http://www.readingrailroad.org/
According to information in the 2008 Walthers catalog, Atlas code 83 Y turnouts are available in frog sizes 2-1/2, 4, 5, 6, or 8. The Atlas code 100 Y comes in only one size, which seems to match their Snap Switches. Peco make two sizes in code 100 rail, listed as small and large. I haven't seen any Peco Y turnouts in code 83 rail yet. The Walthers (Shinohara) Y turnouts come in 2-1/2, 3, 4, or 5, code 83 rail.
Walthers makes a No.3 wye (same frog degree as a regular No.6 turnout) but it's currently out of stock. They also make a No. 4 and 5 wye (equivalent to a No. 8 or 10 turnout respectively).
Maybe you should cut the Gordian knot here* and explore Peco, which has a "small radius" and a "large radius" wye in their catalog. If you think you need a No. 6 turnout or like the looks, then I'd go with the Peco large radius wye.
Dave Nelson
*Gordius the king of Phrygia tied up an oxcart with a highly complex knot and it was said that the man who could untie it would rule all of Asia. Alexander came along and instead of untying it, just cut through it with his sword. The phrase has come to mean solving a complex problem in the most simple and direct way possible.
R. T. POTEETDon Z Jim, If you are using a #6 turnout on your layout, the corresponding wye to use would be a #3. Divide the straight turnout frog number by two to get the wye to use with that turnout. #5 turnout = #2.5 wye, etc. Don Z. HUH?????
Research; it's not just for geeks.
I think #6 wye is in N scale only. From what I have seen...
I had anticipated using several #6 wye turnouts on my HO mainline which otherwise will have #6 RH or LH turnouts and 26" radius curves with easements. Searching the various online stores, I see several #4 and #5 wye's, but nothing in a #6 which, or course, is the "universal" turnout frog angle.
Am I missing something or is a #6 wye overkill?
Jim