Q&A with Josh Pocock

Sales Engineer, Positrol


Positrol has a very busy R&D department. What have they been working on recently?

We do quite a bit of engineering work here. Our engineers analyze each part and process and recommend the best solution.

We’ve come out with different types of part sensing, specifically an LED sensing mechanism. Air sensing is the normal method, but this method uses proximity switches to see if the part is present. If it is, it turns on an LED light. It’s more of a visual inspection. We did this on a gang fixture for an automotive manufacturer who was loading ten parts at a time. Because of the automation they were using, they didn’t have to capacity to run air sensing. Now the operator will load all ten parts, hit “clamp,” and they all clamp at the same time. If one of them doesn’t clamp correctly, one of the ten LED lights will be out. It tells him, “Are the parts clamped correctly? If not, which ones aren’t?”

We’ve had a great response to this technology, especially from the companies that found themselves a niche position. We got an inquiry from someone in Mexico about the LED system just this week.

You are a sales engineer. Which workholding products are you promoting heavily?

We promote whatever solutions works for our customer. We’ve got 26 different products, standard products—a wider range than most of our competitors in the industry. When we look at a product or process, we can usually recommend something standard that we have. Our custom tooling is tailored to meet the specifications of individual applications. In our repairs department, we employ a nightshift staff that works on repairs only, to reduce turnaround time for the customer.

We’re always promoting our quick-change products.  One new product in that area is our Top Tooling changeover system which allows jaws and workstops to be changed over without the use of any tooling. We just received the patent on that. At IMTS 2012, we showed a robot making the changeover and plan to do that again this year.

We’re also seeing an increased interest in our Chuck Change® system. It allows you to change one workholding device, pull it off the spindle, and put another one on the spindle—all in just a couple of minutes.  It repeats .0002”—5 microns—at the connection so there is no need to re-indicate the workholding in after the changeover.  This allows companies to keep those spindles turning and the machines making chips.

Positrol has been around for over 50 years. What did you start out making?

We started making hydraulic arbors, then branched out from there, getting into the gear business right away. We grip on pitch diameter, minor diameter—in some applications, we even grip on the major diameter. The hydraulic arbors are the most common, expanding and gripping on the part for grinding, balancing, and inspection operations primarily. The chucks and arbors are sealed—there are no sliding parts. This allows for accurate location to five microns standard and within two microns TIR, depending on the application. A variety of actuation methods are possible including drawbar, tailstock, hydraulic, or manual actuation. The whole process is ideal for gear hobbing, grinding, shaping, or hard turning operations. Positrol chucks are sealed for long trouble-free life and have quick change features, thru spindle coolant, and air sensing capability. We always harden and grind each device for longer life and lower operating cost.

We also have a Rotolock design, formed in the shape of the pitch diameter with a couple thousandths clearance. Once the part is loaded, a section of the spline on the workholding device will twist to lock the part in place. It’s more for hard turning applications. We also have a bevel gear chuck that utilizes pins to locate the part and jaws to pullback on the face for a turning applications. The chucks and arbors are manufactured to exacting standards and precise tolerances.

Tell our readers about Positrol’s Swing Clamp Chucks.

With the Swing Clamp Chucks, thin-walled, irregular, or out-of-round parts can be clamped for turning, milling and grinding without distortion. Out-of-flat parts can be clamped evenly on all points which will eliminate deformation. It allows for parts to be centralized by collets to positively secure the part or by straight/tapered pins

The jaw quantity and position are designed to clamp the part in the optimum locations, and the air sensing capabilities ensure that the part is located against the workstop to maintain parallelism. The results are more throughput, better quality parts, and decreased scrap rate.

All components are hardened and ground for long life to decrease repair costs. These are design features that will give users years of operation. Simply put, these chucks increase uptime and decrease cost.

MORE INFORMATION: For more information on Positrol, visit www.positrol.com. Call (513) 272 0500, or email sales@positrol.com.