The gap is narrowing between applications that require ball screws and those that are suitable for lead screws, and it’s becoming more difficult for engineers and designers to determine which technology is best for their machine. Advances in lead screw designs and materials have given them higher load capacities and better positioning accuracy, making them a sound choice […]
The top 5.5 linear motion stories of 2016
As a writer and editor, it’s always fun (and sometimes surprising) to look back at the end of the year and see what articles our readers were most interested in. And for you, our readers, it offers the chance to take a quick look at what are, at least to some of your peers, important topics […]
When is static load capacity important?
When sizing a recirculating bearing, most designers and engineers focus on bearing life, which is based on dynamic load capacity. This is the load at which a linear recirculating bearing will, with 90 percent certainty, achieve the targeted service life before fatigue occurs. Static load capacity, on the other hand, is the force that causes permanent […]
How to choose linear guide accuracy
When choosing a recirculating linear guide, there are several criteria that need to be specified, including size, preload and accuracy. And although the term “accuracy” is often used in a generic sense, when referring to recirculating ball or roller guides, it designates five characteristics: Height tolerance of the rail and block assembly Permissible difference in height between […]
New multi-axis positioning family from PI
High-end industrial and research applications rely on precision motion stages and systems to execute mission-critical procedures and processes. PI, a leading provider of nanopositioning and motion control solutions, has developed its new family of linear, rotary, and Z-axis stages to meet those demanding requirements. Meet the L-310 vertical stage, the L-611 rotary stage, and the […]
FoodStream Pillow and Flange Blocks: FDA/USDA and 3A-Dairy Compliant
FoodStream electroless nickel plated pillow and flange blocks from LM76 are FDA/USDA/3A-Dairy compliant linear motion components. They complement LM76’s line of FDA compliant bearings, scraper seals, and shafting. FoodStream off-the-shelf pillow and flange blocks are ideal for use in processing and packaging food, producing pharmaceuticals, the BioPharma industry, and in medical devices. Inch size FoodStream […]
How to choose linear guide preload
When choosing a recirculating linear guide, one of the key criteria in the specification is preload. Linear guide preload eliminates the clearance between the bearing block and the rail, which increases rigidity and reduces deflection when external loads are applied. To achieve preload, manufacturers use balls (or rollers, in the case of roller bearings) whose diameter is […]
What is stick-slip?
Stick-slip, also referred to as “stiction,” is the bane of engineers and machine builders who need smooth, precise motion. Simply put, it’s the jerkiness that can plague both plain and recirculating linear bearings when they transition from standstill to motion. Here’s why stick-slip happens… When two objects slide against each other, friction works against their motion. […]
The good old days…they were terrible!
That was the mantra of my Technology and Society professor in college. And in many cases, I have to agree with him. While we like to romanticize the “good old days,” when things were simpler and more straightforward, how many of us would really want to go back and work in the era of slide rules […]
Drive nut runs on threaded shaft
Amacoil-Uhing model RS drive nuts provide smooth backlash-free linear motion in machine design. Unlike a screw, the RS drive nut runs on a smooth shaft. This eliminates the potential for debris to become trapped in threads which could then clog or jam. If material does fall onto the shaft, it is easily removed by wiping the […]