A reader asks: We are currently revising our gear standards and tolerances and a few questions with the new standard AGMA 2002-C16 have risen. Firstly, the way to calculate the tooth thickness tolerance seems to need a "manufacturing profile shift coefficient" that isn't specified in the standard; neither is another standard referred to for this coefficient. This tolerance on tooth thickness is needed later to calculate the span width as well as the pin diameter. Furthermore, there seems to be no tolerancing on the major and minor diameters of a gear.

A reader asks: We are currently revising our gear standards and tolerances, and a few problems with the new standard AGMA 2002-C16 have arisen. Firstly, the way to calculate the tooth thickness tolerance seems to need a "manufacturing profile shift coefficient" that isn't specified in the standard; neither is another standard referred to for this coefficient. This tolerance on tooth thickness is needed later to calculate the span width as well as the pin diameter. Furthermore, there seems to be no tolerancing on the major and minor diameters of a gear.

Our international readers are no doubt chuckling over this silly, American “long addendum” terminology. The “civilized world” has long relied on a ...

The initial motivation for changing outside diameters was the avoidance of undercutting. Designers, engineers, and theoreticians quickly discovered...

Imagine for a moment that your boss invented the herringbone tooth form and tasked you with building machines to cut them. This was the situation P...

Not to worry — no politics here. The “backlash” I want to talk about is the “lost motion” in gear systems. It sometimes seems to rile people up alm...

In terms of the tooth thickness, should we use the formulation with respect to normal or transverse coordinate system? When normalizing this thickness in order to normalize the backlash (backlash parameter), we should divide by the circular pitch. Thus, when normalizing, should this circular pitch be defined in the normal or traverse coordinate system, depending on which formulation has been used? Is the backlash parameter always defined with respect to the tangential plane or normal plane for helical gears?

The great thing about a trade show the size of IMTS is the amount of options available to attendees. If you’re into cars, fighter jets, machine tools, fighting robots, manufacturing relics or simply the latest technology advancements in a particular industry, you’ll find it at IMTS 2010.

The two-flank roll test measures kickout (tooth-to-tooth composite error) and tooth thickness. In this article, it will be shown that measured values vary with the number of teeth on the master gear.