Differences in Nathan P Horn Generations

[NickN]

Well, someone's got to be first...

A very useful thread on the old forum that is now not able to be read, was a question on the differences in the castings of the various Nathan P Horns: not just what the differences are between old cast and new cast, but what exactly the 'ovals' and 'ghost ovals' are, and when those changes happened.

Would someone be kind enough to deal with this, both the differences in 'old' and 'new', as well as the ovals business? Photos would be even better!

Thanks.

[Flat Train]

Ok, So the oval inlets were basically the prototype P horns. Not many oval inlet P horns were made. They were produced from the early 50's to 1957 I believe. The Inlets are the little hole at the bottom of the foot of the bell that lets air into the diaphragms. The difference between "new" and "old" cast is that the P5 was originally supposed to play the notes C#, E, G, A, and high C#. Those are the old cast notes. Old cast bells also say "Pat Pending" Where new cast would say "Pat Pend" on the side of the foot of each bell. The #4, 4A, and 0 bells don't change from old cast to new cast.

[Railgeek]

Here's my oval inlet P1. You can see the inlet under the retainer spring and the diaphragm seat.

[Flat Train]

Here's my oval inlet P1. You can see the inlet under the retainer spring and the diaphragm seat.

Can't seem to view the image. Maybe its what i'm viewing it on.

[Railgeek]

Can't seem to view the image. Maybe its what i'm viewing it on.

Should be available now.

[Flat Train]

Can't seem to view the image. Maybe its what i'm viewing it on.

Should be available now.

Yep. See it now.

[NickN]

Ok thanks guys, very helpful. So the ghost ovals I have heard talked about? Are they basically on all old cast P horns after the 'proper oval' stopped?

[Flat Train]

Ok thanks guys, very helpful. So the ghost ovals I have heard talked about? Are they basically on all old cast P horns after the 'proper oval' stopped?

The ovals stopped around 1958 or so, then it went to a circle.