Hand-piece Housing/cover

I visited your forum recently. I liked all the correspondences and transfer of know-how to people who really need it. You are doing a great work.
I am a mechanical design engineer with no experience in Ultrasonic processing. I have started reading about the basic concepts and got a lot from your web site and manufacturers' web sites . I do not have a device and I do not know yet when I will acquire one. At this moment, I am interested to know the design of a system used to cut (plunge cut in the axial direction) soft materials like meat or potatoes. I have a couple of questions?

1- I would like to attach a stationary housing or handle that covers the hand-piece all the way to the frontal tip close to the tool. The purpose of such a housing may be to locate the tool tip precisely. I assume that the housing should be connected to a nodal flange or flanges. The nodal flange I think may be on the frontal mass or the booster or the horn? The nodal point with zero amplitude is a line contact (like a shoulder on a stepped horn). We know that a flange has a finite width. What is the effect of a wider flange at the nodal point? How is the flange connected to the horn? Can a housing be connected at more than one nodal flanges assuming that a booster and a horn are used? Can I find some example drawings somewhere?

2. Is it possible to get a rotary ultrasonic motion and how? Where can I get some literature to read? Are there manufacturing companies out there?