Engineering Manager,

Subject: Report on Trichotometric
Indicator Support.

I want to thank you for the excellent sketch and the accompanying instructions for the support bracket designed by your company in May 1992 for the purpose of improving the operation of the Trichotometric Indicator used on the current model machines.

Your advice reached us at a time when we were experiencing particular difficulty with compound transmission of the pandemonial support pins. The difficulty seems to be caused by the old style hex-nut.

Since the old style hex-nut, due to its design, had to be screwed off to be screwed on, the only way to tighten it was to loosen it. Our maintenance people felt that the new ambihelical nut, by reason of its inherent design feature, which dictates that it must be fully screwed on before it can be screwed off, would solve the problem of becoming looser when it is tightened in that it must be loosened to tighten it and therefore should become a logical replacement of the older nuts which had to be fully screwed off in order to screw them on and consequently become tighter as they were loosened instead of looser as they were tightened.

A further problem of less alarming proportions become immediately apparent when it was recognized that a training program would need to be instituted to acquaint the field serviceman, with the complexities involved in loosely tightening as opposed to tightly loosening. Some of our maintenance people are actually not clear on this point.

Upon adoption of the suggested May 92 modification to the Trichotometric Indicator on our machines of your manufacture, the project was turned over to our machine shop for fabrication.

The machinist experienced some difficulty in lay-out of the rectabular extrusion bracket. Since the thickness at one end of the bracket becomes part of the width at the other end, it is difficult to determine whether the thickness is wider than the width or whether the width is thicker than the thickness. When the bracket is laid down flat it is actually standing on edge and therefore must be stood up to lay it down.

Therefore all horizontal holes must be drilled vertically and all vertical holes horizontally, except when the bracket is in the horizontal plane, which can only be achieved by mounting it vertically.

Our machinist was fortunate in being able to pick up this little twist in a very short time. Your instruction sheet would be greatly improved if the procedure for fabrication of this part was clearly outlined as above.

As soon as the first model was completed our mechanical staff installed it on the subject machine. Despite detailed instructions on how to install the indicator support bracket, the mechanic had considerable difficulty in establishing the correct torque between the ambihelical hex-nut and the indicator support.

Since conventional handling produced inverse results, he found that he had to turn the nuts to the left in order to make them go the right. Once this difficulty was overcome, assembly proceeded well, but in reverse.

The new installation seems to be performing well in service and indicated a very distinct departure from the previous model in operating characteristics. The modified version, instead of requiring loosening to tighten it, performs this function automatically, in that as the machine shakes apart during operation it gradually tightens up.

This design feature should be guarded most cautiously and held in utmost confidence by your Company. At the moment this improvement may well be the factor by which your Company outranks all competitors for leadership in this field.

R. Ippnoff
Engineering Dept.