[Shdwdrgn]

So I was looking through some prototype pictures of turnouts this morning and happened to notice something new... Some turnouts have a curved point on one side to match the turn of the diverging route, while other photos showed both points were dead-straight.

To me, logically, you would want the track to have a smooth curve into the diverging route rather than an immediate angle. It did look like the straight points led into a curved diverging route though. Unfortunately the photos were too close-cropped to tell if they were part of a yard, a mainline, or something else, so I can't really give any reference to how they were used. It just struck me as odd that the points wouldn't always be bent to flow smoothly with the curve of the diverging route.

Any thoughts on this?

 

[mesenteria]

I agree, but I think the matter depends on whether the points are jointed or solid. The longer solid ones will be curved, while most of the jointed points will have a straight section followed by curved closure rails. Also, straight points would necessarily be for slow-moving trains, whereas the eased geometry would be for higher speeds.

 

[Shdwdrgn]

Ah that does make sense, and from the geometry I saw in the pictures the ones with the straight points were definitely jointed.

 

[traction fan]

curved points

So I was looking through some prototype pictures of turnouts this morning and happened to notice something new... Some turnouts have a curved point on one side to match the turn of the diverging route, while other photos showed both points were dead-straight.

To me, logically, you would want the track to have a smooth curve into the diverging route rather than an immediate angle. It did look like the straight points led into a curved diverging route though. Unfortunately the photos were too close-cropped to tell if they were part of a yard, a mainline, or something else, so I can't really give any reference to how they were used. It just struck me as odd that the points wouldn't always be bent to flow smoothly with the curve of the diverging route.

Any thoughts on this?

Shdwdrgn;

I'll go with mesenteria's explanation regarding prototype turnouts. I think he has prototype working experience, and I know that I do not. On model turnouts, most are two straight routes diverging from each other at the frog angle, and have both points straight. Some, including Atlas Snap Switch turnouts, and all curved turnouts, have an actual curved diverging route. Both Atlas points come from the factory straight, but the one that wheels ride into the curved diverging route can benefit from being bent into a curve that matches the overall curve of that diverging route. Sometimes the point rails will form a tight spot when measured with an NMRA gage, until this curve is put into one. So they may end up with a sort of model version of what you saw on the prototype turnouts, though not for the same reason. Curved turnouts, of course, have both points curved, simply because both routes are curves.

regards;

Traction Fan :smilie_daumenpos:

 

[gregc]

i think as the frog # gets smaller, the diverging points get more curved