Rotax cross-section photo

[bort]

A long time ago, I remember seeing either an illustration or a photo of the cross-section of a rotax rotor. I can't seem to find it now, though, because it was either a deleted board attachment or something that was linked to photobucket.

Anyone know where I can find it?

Thanks!

(I don't need to get into the particulars and pro/con arguments of Rotax valves...)

[bort]

Thanks Joe! That helps a bit. I also remember a graphic from the Willson website or something from long ago. I guess I could also search for the Rotax patent filing, which would have diagrams, too.

No true need or point to this, only trying to better understand my own stuff!

[joh_tuba]

What Bloke said. I've ranted about this more than once on this forum.

Any tuba rotor larger than 16 or 17mm already has a reduction in the pipe when passing through the rotor. Adding more material only exacerbates this issue. Removing material is sort of a no duh zero consequence procedure.

[bort]

As many times as I have read Joe's description, I still have trouble "getting" it... spatial reasoning just isn't my thing. I will just have to pop out one of my valves sometime and see for myself.

Regardless of the bore straightness or reductions, my tuba is very open and has little resistance. Not trying to argue anything, just tell what i observe.

The valves might win the speed competition, but then again, neither would my fingers.

It would be interesting to know what my tuba would be like with the usual Meinlschmidt rotors, but clearly, that would be an excessive project, especially just to find out!