Anyone know what the purpose of..........

[DoubleDiamond]

Unfortunately commercial turnouts are made to accept many variations in wheels - tyre width & flange depth.

Ideally tyre widths & flange depths work well when flangeways are all the same and especially at the frog point, tyre widths are in reality, wide enough to bridge the gap and be supported by rail all the time. This can be achieved in the model as well but one has to accept having all the same wheel profiles.

Yes Ron, tyre width I get. What I don't understand is why are the wing rails raised? Why not just have the same rail depth over the frog as the rest of the track?

Anyway, looking again at some points, I noticed on a Peco point, the raised wing rail just in front of the 'V' (even though it's tiny), has a little ramp. The Hornby one however, is more, lets say, abrupt.

Therefore, it seems the Peco points introduce the loco wheels to a smoother run up into the wing rails in the 'V'.

That's my understanding of it.........I think

[DoubleDiamond]

That's some intricate work there MG, very impressive.

British engineering is still alive and kicking

[Ron S]

DD, I think the first photo you posted was not a Peco turnout but a Hornby based on the large plastic V

Now i have a latest Peco Code 100 insulfrog and yes, the older style wheels say from Lima with their pizza cutter flanges, do ride up a bit through the frog area and I fixed the problem by replacing any such wheels sets. Current wheels from Bachmann, etc run through no problems.

[Walkingthedog]

Modern wheels don’t touch the plastic, they cross the frog seamlessly. Hornby points are not anywhere near as good as Peco, far too much plastic. My rolling stock doesn’t ride up on the plastic or drop into a void, apart from the old point I mentioned. If you use modern track with older large flanged wheels you may have problems.Curved points do appear to cause problems for some people, not sure why.

[Ron S]

Wheels with narrower tyres such as some Coopercraft & those to NMRA RP25-88, at times drop into the frog area on large radius turnouts.

[DoubleDiamond]

DD, I think the first photo you posted was not a Peco turnout but a Hornby based on the large plastic V

Now i have a latest Peco Code 100 insulfrog and yes, the older style wheels say from Lima with their pizza cutter flanges, do ride up a bit through the frog area and I fixed the problem by replacing any such wheels sets. Current wheels from Bachmann, etc run through no problems.

That's right Ron, Hornby point. That's just a normal left hand one, my attempt to show a close-up of the 'wing rails'.

Changing the wheels didn't even enter my head. Wouldn't have the technical knowhow or dosh anyway. Trying to sort the points seemed logical to me.

It was only the small pony truck wheels on the class 40 that caused a problem. After a little whizz with the Dremel in the 'V' and everything's fine now.

[DoubleDiamond]

Hornby points are not anywhere near as good as Peco,

Seems you may be right WTD. Wish I'd have known all this when I first started.

Just a big learning 'curve' isn't it

[Ron S]

The small pony truck wheels may also not have the ideal back to back measurements

http://www.doubleogauge.com/standards/c ... wheels.htm

[Ron S]

Hornby points are not anywhere near as good as Peco,

Seems you may be right WTD. Wish I'd have known all this when I first started.

Just a big learning 'curve' isn't it

I guess if track is purchased from a "toy" shop , they may not necessarily know that Hornby track is not as good as Peco but from a Hobby shop, they should know the better items to use or at least the differences..

[DoubleDiamond]

"I guess if track is purchased from a "toy" shop , they may not necessarily know that Hornby track is not as good as Peco but from a Hobby shop, they should know the better items to use or at least the differences".

It was me who didn't know the difference