Matthias,
Typical numbered tap and die sizes are based on a simple formula. A "zero" die, such as a 0-80 size, is for rod that is 0.060" diameter. For each number size above or below zero, add or subtract 0.013" to the diameter. So, a 1-72 die is for rod that is (0.060" + 0.013"), or 0.073" diameter. A 2-56 die is for rod that is (0.060" + 0.013" + 0.013"), or 0.086" diameter. A 3-48 die is for rod that is (0.060" + 0.013" + 0.013" + 0.013"), or 0.099" diameter. For smaller dies, such as 00-90, it is (0.060" - 0.013"), or 0.047" diameter rod.
To determine the drill size for a tapping hole, subtract (1 divided by thread pitch) from the diameter of the wire. So, for a 0-80 tap the tapping hole diameter would be (0.060" - (1/80)"). For a 1-72 tap the hole diameter would be (0.073" - (1/72)"). For a 2-56 tap the hole diameter would be (0.086" - (1/56)").
For your 1/16" rod which is nominally 0.063" diameter, a 1-72 size die will work as long as shallow threads are acceptable. A 1-72 nut may be a little loose on rod of that size. The rod will be a loose fit in a 1-72 tapped hole. There are other tap and die standards such as the British BA and ME series and various metric series that may be a better match for 1/16" rod. Try a Google search for taps and dies. You should come up with several hits that list the various thread series with the nominal diameters that are intended to be used with each die. I'm on the road this week so I don't have access to my web site lists that have the tables of tap/die/wire diameters on them.
Casey Sterbenz
From: Matthias Warmbold <[EMAIL PROTECTED]> Reply-To: [EMAIL PROTECTED] To: Multiple recipients of sslivesteam <[EMAIL PROTECTED]> Subject: die size for 1/16" rod Date: Thu, 19 Aug 2004 22:55:45 -0700 (PDT)
Hi,
I got a 1/16 brass rod (K&S brand) on which I would like to put a thread. Neither the shop nor K&S has provided me with information on which die is suitable for this size. I spent some time surfing the net and assume that a 00-80 die would fit. To make the female thread, I assume that I have to use a 3/64 drill bit.
Can anyone from this list confirm whether my assumptions are correct? K&S sells a 00-80 tap and die which no local dealer has on stock. Are they of good quality or should I order it from somewhere else? Are there any tables on the Internet where one could look up the die size for any given rod?
Matthias
