The World of ACME Screw Threads

In my younger days I thought ACME was the name of a company that brought Wile E Coyote the newest innovations on how to catch a Roadrunner, but as I have grown older I realize ACME is an important thread in every day uses.

The word ACME as defined by Merriam-Webster is: the highest point or stage; or: one that represents perfection of the thing expressed. So if we take the definition for what it is, when it comes to screw threads, ACME is the best thing going. When formulated in the mid 1890's, ACME screw threads were intended to replace square screw threads and a variety of screw threads of other forms used mainly for the purpose of producing traversing motions on machines, tools, etc. ACME screw threads are now extensively used for a variety of purposes. Problem is, it can be a pretty confusing screw thread to deal with if you're not sure what you're looking at. I hope to clear it up for you here.

There are 3 different forms of ACME Screw Thread: General Purpose ACME, Centralizing ACME, and Stub ACME. General Purpose ACME Screw Threads and Centralizing ACME Screw Threads can be found in ANSI B1.5 while Stub ACME Screw Threads can be found in ANSI B1.8. While the three different variations of the ACME screw thread are not all listed in the same standard they do share some similar characteristics. All three styles of ACME screw threads have 29° included angle; all are perceived as a bilateral transverse motion screw thread; all offer high strength with ease of machining and assembly; and all are largely used for feed and adjusting screws.

Originally Posted: 12/9/2008
Last Revised:

If you discover error or wish to comment on this page contact Wayne at:gageguy@gagecrib.com