Bearing-reinforced Stepper Tackles Hefty Axial Loads

These days, it’s common among us hackers to load a stepper motor with forces in-line with their shaft–especially when we couple them to leadscrews or worm gears. Unfortunately, steppers aren’t really intended for this sort of loading, and doing so with high forces can destroy the motor. Fear not, though. If you find yourself in this situation, [Voind Robot] has the solution for you with a dead-simple-yet-dead-effective upgrade to get your steppers tackling axial loads without issue. In [Voind Robot’s] case, they started with a worm-gear-drive on a robot arm. In their circumstances, moving the arm could put tremendous axial loads onto the stepper shaft through the worm–as much as 30 Newtons. Such loads could easily destroy the internal stepper motor bearings in a short time, so they opted for some double-sided reinforcement. To alleviate the problem, the introduced two thrust bearings, one on either side of the shaft. These thrust bearings do the work of redirecting the force off the shaft and directly onto the motor casing, a much more rigid place to apply such loads. This trick is dead simple, and it’s actually over five years old. Nevertheless, it’s still incredibly relevant t...

What Happens When the Timbers Army Stops Cheering? National Media Coverage, and an Allegedly Angry Owner

In protest of a recent Major League Soccer ban on flags and banners bearing an antifascist symbol, Portland and Seattle soccer fans decided to spend the first 33 minutes of the game in silence. The Timbers Army didn’t lead cheers or songs, nor did they create a tifo—a massive banner the coalition of fans typically constructs for rival games. The demonstration was a response to a May rule change in MLS’s code of conduct that deemed the Iron Front symbol—a circle encompassing three arrows—overtly political. The Iron Front symbol was an emblem of a WWII-era socialist, paramilitary organization that opposed the Nazi party. It was disbanded in 1933. In an Aug. 19 statement, the Timbers Front office wrote that MLS “believes the Iron Front symbol is inherently political because it has been co-opted by antifa.” Fans and players both denounced the ban on Friday. In addition to Iron Front flags scattered throughout the crowd, Timbers defender Zarek Valentin and Thorns forward Christine Sinclair both entered the stadium in shirts bearing the symbol. At halftime, The Nation reported, players from the rival teams exchanged jerseys as a show of solidarity. At the end ...