Walthers Shinohara curved #7 switch radii??

[Gary UK]

Can anyone tell me the radii of the above curved switch on the inner curve please?

The #6 is 24' and 20'  if it helps.

Thanks.

 

[selector]

I believe it is 28", but it may be closer to 30".  I just did a quick swipe with a tape measure on one of my #7.5 curved turnouts, and I got 28"ish.

You do mean the #7.5, right?

[Don Z]

The Walthers #7 claims to have an inner radius of 24" and an outer radius of 28". I laid out a series of arcs on a piece of plywood to test their claims and determined that the #7 is actually a 20.5" radius on the inner and is 28" on the outer radius.

Don Z.

[Gary UK]

Near enough, thanks guys.

Gary.

[dante]

Don,

I checked my #7 (not yet installed) and approximated 21" - to my disappointment because I was counting on the 24". I checked my other stockpiled curved switches and found the #7.5 and #8 to be accurate; however, I have a #6 labeled by Shinohara to be 24"/20" that measures 24"/18". Walthers listing shows a #6.5 @ 24"/20". Anyone know what gives with these inconsistencies? (With one exception, all my turnouts are pre-DCC-friendly.)

[Don Z]

Dante,

When I first noticed this on my layout, (the curved turnout wasn't aligning with my centerlines I had drawn) I called my LHS dealer and told him of the problem. He came to my house to verify my drawings and the turnout. When he called his Walthers rep, the rep admitted they have known for some time that the dimensions in the catalog are incorrect, but they have never taken the time to actually calculate the correct radii for the curved turnouts.

I took each size of the Walthers curved turnouts and laid them over my test plot where I had drawn many radii to figuure out what the actual radii are. Here is what I discovered:
#6.5 turnout - Walthers claims 24" outer, 18" inner - Actually 24" out and 16.5" inner
#7.0 turnout - Walthers claims 28" outer, 24" inner - Actually 28" out and 20.5" inner
#7.5 turnout - Walthers claims 32" outer, 28" inner - Actually 32" out and 24.0" inner
#8.0 turnout - Walthers claims 36" outer, 32" inner - Actually 37.5" out and 30" inner

Don Z.

[dante]

Don Z.,

Thanks for the quick response. Note that you and I are getting different results. I'll have to recheck my measurements, which were based on comparisons of the actual switches to computer-generated radii, printed. I am still puzzled by Shinohara's own designation - cast into the bottom of the ties - of the #6 (not #6.5) as a 24/20 when it is clearly more likely 24/18. And your measurement of a #6.5 as a 24/16.5 although logically, it should be more gradual than the #6.

Oh, well - we have a local train show this weekend; I'll try to compare what I have to any Walthers switches that may be displayed by vendors. This could shatter my proposed layout plan which depends greatly on curved turnouts to squeeze what I want to do in a tight space without unduly tight radii!

Thanks again.

Dante

PS. Do your turnouts have the data cast into the underside of the ties as mine have?

[selector]

I searched for the largest curved turnouts I could get in a hurry, and the seller quoted the literature when I asked for the inner radius of the 7.5's he had.  I think the answer was 28", so I was very happy.  When I went to install them on my centreline, you can guess my dismay when there was an obvious problem.

My solution...and you need to sit down for this...I cut small chunks out of the tie webbing under the diverging route and in the ties between that and the outer route.  This allowed freedom to extend the radius of the inner route.  I even had to cut the metal jumper. Then, I used track nails and bent the diverging route toward the through route tracks into the proper configuration.  So far, I have had no issues, I am pleased to say.  The frog angle does not present a problem.

[FastTracks]

Hi All,

I noticed this "phenomon" a while back when working on some designs for curved turnout assembly fixtures.  At the time I wrote a bit of a white paper on the subject, and posted it to our discussion forum.

This post can be found here...

Tim Warris
Fast Tracks

[dante]

To recheck my curved turnout sizes (Walthers/Shinohara Code 83), I built a homemade beam compass, laid-out arcs and overlaid the turnouts. The results are:

• #6/#6.5: 24/18 (frog# depends on whether you believe the box label or the imprint on the turnout!)

• #7: 28/22

• #7.5: 32/26

• #8: 36/30

I also checked a #4 Code 70: with a 22" radius for the closure rail, it must actually be a #4.5.

Thanks to Tim for an informative exposition of the design of curved turnouts. Tim, whatever you do in FastTracks for curved turnouts, please publish accurate radii - that is more useful information than frog numbers, it seems to me.

Dante

PS. Back to the CAD drawing board to revise the plan!

[fwright]

Now the question becomes:  are any of the curved turnout track libraries in planning software accurate?  Or do they just take the manufacturer's published specs?

inquiring minds want to know

Fred W

[dante]

Fred,

I use Empire Express on the Mac. Their current Walthers library appears to use the published sizes. When I started using this app, the library was not so complete or up-to-date, so I made my own (also using published sizes, but trying to be accurate regarding length of turnout and location of the start of the diverting radii - tips of the points). It wasn't too difficult because the app displays track centerlines, not both rails. I will now have to change the inside radii on my library turnouts.

Dante