Close up of Rolls

Click below for details on our Spin Rolls:

Spin Rolls - Brochure (pdf)

Spin Rolls - Overview

Spin Rolls Grinding - Overview

Spin Roll 500 Series:
500 D * 500 M
500 PT * 500 VP

Spin Roll 525 Series:
525 M * 525 P

Spin Roll 530 Series:
530 M * 530 PT * 530 VP

Spin Roll "V" Block Inspection - Overview

"V" Block Product Line:
RVM 100 * MRV-10

Spin Roll - Comparison Chart

Spin Rolls 

Spin Rolls & Rotary "V" Blocks - The original....The best.

Patented by our founder Mr. John Kopczynski Sr.

Spin Rolls - (click here for Grinding Product Line details...)

St. Mary's unique Spin Roll work holding fixtures provide low-cost, precision cylindrical grinding or other machining capabilities. A patented design, employing three intermeshing contact rolls, assures precise, repeatable, automatic linear positioning and concentricity up to .0002".

Available in nine manual and motorized models, Spin Rolls mount easily on many standard shop machines, including most internal, cylindrical (ID & OD) or surface grinders, drill presses, finishing, cutting, chucking, and other machine tools.

Standard models accommodate workpieces from 1/64" to 3" diameter and 5/8" to 5" lengths, with an optional mounting bracket on Model 525-P for lengths up to 20".

Workpieces can be loaded quickly, easily and accurately, allowing the Spin Roll to be used efficiently for both prototype and production machining.

Automatic concentricity (within .0002"), linear positioning, and precise duplication for any number of workpieces are assured by the Spin Roll's three intermeshing contact rolls which revolve and rotate the cylindrical piece on its own circumference.

Rotary "V" Blocks - (click here for Inspection Product Line details...)

With St. Mary's Rotary "V" Block, the concentricity and straightness of circular or round shafted objects can now be inspected quickly, (to within .00005) safely and accurately by a practically unskilled operator!

Just insert the workpiece between the three intermeshing contact rolls and against the end stop which has been adjusted to the length required. The workpiece rotates on its own circumference, achieving precise concentricity while maintaining linear positioning. Because of the greater ratio of diameter of rolls to diameters of workpiece, the workpiece makes many revolutions per turn of the rolls.

The rolls in the Spin Roll Rotary "V" Block are especially lapped for true roundness. The female contact rolls are mounted on dead centers and the intermeshing (or clamp) roll is mounted on a permanently sealed bearing. The rolls are so true that only a slight turn of the clamping roll provides for accurate checking of any diameter by means of a mechanical or electronic indicator or optical comparator.

The Spin Roll Rotary "V" Block loads, locks and releases quickly and simply by means of its adjustable spring loaded arm. Assures exact duplication on multiple runs

A Micro Rotary "V" Block (Model MRV-10) is also available for inspection of small circular parts requiring true concentricity (within .00005).