Converting american screws sizes to decimal

October 12, 2005

Most american screws (non-metric) under 1/4″ are named by their number and thread pitch (thread per inch). So a 10-32 and a 10-24 are the same diameter (#10), one is fine thread and one is coarse. To calculate the diameter you multiply the number by .013″ and add .060″. A #10 is therefore .060 + (10*.013) or .190″ (about 3/16″). I plugged the formula into a spreadsheet and calculated some common sizes.

Sure, you can look it up online or in Machinery’s Handbook, but if you know the formula (and even a lot of machinists don’t) you can calculate the screw diameter anytime.

1 Comment »

The URI to TrackBack this entry is: http://gastiresoil.blogsome.com/2005/10/12/converting-american-screws-sizes-to-decimal/trackback/

  1. Quite inspiring,

    This is really helpful for the piece of furnature i had imported and i couldnt follow the instructions,

    Anyway, thanks for the post

    Comment by software development uk — October 28, 2009 @ 3:51 am

RSS feed for comments on this post.

Leave a comment

Line and paragraph breaks automatic, e-mail address never displayed, HTML allowed: <a href="" title=""> <abbr title=""> <acronym title=""> <b> <blockquote cite=""> <code> <em> <i> <strike> <strong>


Get free blog up and running in minutes with Blogsome | Theme designs available here