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I work in N scale so I can't really comment on the larger gauges, but I'll give you my experiences with N in that regard.
I was working on a number 4 wye turnout for someone, when the decision to use either hinged or fixed heel points had to be made. The decision was going to be based on how difficult it was to throw the turnout in each position.
What I've found is that the point rail thickness (and more importantly how consistent the thickness is) is going to be a factor on how the points bend. I did relieve some of the stress on the rails by notching the points web by the heel, (just after the solder point and tie) this helped some.
If while grinding the point rails you make them to thin on the blade end they will tend to bend where its thin and the stiffer part of the rail will resist bending. What I did was to remove more rail base throughout the point up to the solder point tie (the heel) I hope your following this)
Insure the heel of the points, (this is the end where they are soldered to the pc tie is right on or just a hair wide on gauge, use the NMRA gauge. I use a pivoting point attachment on the throwbar, so the stiffness of the points to throwbar isn't a factor.
My main concern on the difficulty of throwing the points, was going to be the reliability of the point heel attachment. Although tortoise machines will throw the turnout (aka bend the rails) I didn't want the turnout to fail at its stress point, that stress point was now at the heel of the points vice the throwbar soldered connections. Cutting gaps in the web by the heel allows the rail to bend at that junction somewhat easier. Some folks worry about metal fatigue, but the throw is so short it shouldn't be an issue.
One other thing, is make sure there is a curve in the point rail that follows the jig. I know the first few I made I just put the rail in without bending a curve in the point rail. Because I didn't put a curve in it, it had some torque in it and wanted to straighten out.
So when it bent (throwing the points) it tightened the gauge somewhat) bending the point rail to the curve, notching the base just after the pc tie solder point, and having a pivoting throwbar should eliminate the gauge tightening for you.
Let us know how well the above works out for you!
Rob
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