Pulley Tap or Extension Tap - It’s a Reach!

Pulley Tap or Extension Tap - It’s a Reach!

Here’s another example of legacy term confusion. Sometimes it is necessary to use a tap with extended length. The added length may be used to add “reach” to the tool, or to allow tapping to a depth longer than the thread length of the standard blank. Maybe it’s necessary to accomplish both! The confusion lies in what to call that style of tap.

Tags: extended reach, Extension Tap, Pulley Tap, small shank

Once Upon a Time There was a Magical Form Tap

Forming Tap History, History of the Form Tap

If you follow any industry long enough, history will become a useful tool to apply to your understanding of modern developments and designs. One such piece of history, as related by someone who was there in the 1950’s, will create an illustration of the importance of learning from errors, and creating opportunities.


Once upon a Time, not so far away, a tap manufacturer with a long history in the industry made an error processing a manufacturing order. We all do from time to time. Where it went from there is the story.

Tags: Chip-less Tap, Form Tap, History of Form Tap

Tandem Taps - Where You Lead, I Will Follow

Tandem Taps - Where You Lead, I Will Follow

Tandem, originates from the Latin meaning “at length”, first seen in modern language in the late 18th Century to describe any two things working together, “in tandem”.


Close your eyes and say the word “Tandem”. What do you see? A bicycle built for two? A stroller made for two children? What about a semi-truck pulling two trailers down the highway? The more adventurous might envision a tandem sky-dive or a 2-person kayak.


For this blog, I will concentrate on Tandem Taps. This may not sound as fascinating as the examples already shared, but some knowledge is worth the pain. Tandem taps are a special type of tap that includes two or more threaded sections for creating internal threads.

Tags: Acme, application specific taps, Tandem Taps

Holiday Greetings from North American Tool - 2017

Holiday Greetings from North American Tool

Check out our short video wishing you all a Merry Christmas and a Happy New Year!

Hand Taps vs. Machine Taps - Are Some Terms Past Their Expiration Date?

Hand Taps vs. Machine Taps - Are Some Terms Past Their Expiration Date?

“Hand Tap” and “Machine Tap”, are terms that don’t always mean what you might think! These are stale industry “legacy” terms. Originally meant to define a purpose, they can be misleading to people in the industry. They should not define a tap’s modern method of use.

According to some handbooks, the term “Hand-Tap” has traditionally been applied to fractional size taps having a standard general purpose length. Most manufacturers don’t limit the description to fractional sizes. Assumed to be straight-flute, these are taps whose flutes are provided as a space to accommodate chips created as the tap cuts.

Tags: Hand Tap, Machine Tap, Spiral Flute, Spiral Point, Tap Terminology

Do you have a Need for Speed? Use Multiple-Lead Threads...

Do you have a Need for Speed? Use Multiple-Lead Threads...

When you have a long way to go, and a short time to get there, there's a thread option available. Multi-start, also known as multiple-lead taps create a thread that offers quick assembly and disassembly. Most of us take these type of threads for granted, but see their use daily. From the caps on water and juice bottles, to the handles on our bathroom faucets, multiple-lead threads make life a little bit easier.

Tags: Multi Lead, Multi-Start, Multiple Lead, Multiple Start

SPECIAL TAPS = Solutions at the Highest Level

SPECIAL TAPS = Solutions at the Highest Level

First Level Solution

Standard taps have features that satisfy most applications. They are “General-Purpose” taps for this reason. Dimensionally, they try to hit the sweet spot, and check most of the common boxes.  Shanks and squares are accommodated by standard tool holders. The lengths of the tool, and length of thread, are sufficient for most set-ups and part requirements for depth of thread. Pitch-diameters are safely above the Go Gage to produce the specified Class-of-Fit for finished thread, and still distant enough from the “No-Go” to avoid any risk of producing oversized thread. Easy, in a cookie-cutter world, but not always that simple.

Tags: application specific taps, High Performance, Special Tap, Standard Taps

All These Flutes...and No Music??

All These Flutes...and No Music??

A question was recently asked,” If Spiral-flute taps will work in both blind and through holes, why do I need a Spiral-point?” Sounds a bit like the lyrics to a sad Country song.


The answer to the question lies in the details of the application. Technically, all flute configurations will make threads in both “through” and “blind” holes. The decision on which is appropriate is based on producing desired chip flow. Chip evacuation is an issue that contributes heavily to the success, or failure of a tap. Also remember that flutes accommodate the volume of coolant or lubricant applied, not just the material chips created in the process. It can get crowded in there!

Tags: Gun Taps, Hand Taps, spiral flute taps, spiral pointed taps

From Skinny Jeans to Loose Fit; Taps Have Class of Fit

 From Skinny Jeans to Loose Fit; Taps Have Class of Fit
Imagine you are trying on a new pair of pants. Your waist size dictates the class of fit. You are the bolt. Unfortunately, the likelihood that you find a pair that fits perfectly is rare. Too tight and too loose are immediately obvious. (I know it's a stretch from making threads in metal, but stay with me.) Now imagine that tight is the "Go" gage, and loose is the "No-Go" gage. Anywhere between the two, is acceptable. Maybe not completely comfortable, but acceptable. Thankfully, you have the ability to "fine-tune" the fit. You buy a belt. The notches in the belt are the "H-limit's". The first notch is very close to your waist size. The last notch barely stops your pants from falling down. Every notch in between changes the way you, and your pants, fit together.

Tags: Class of Fit, Go Gage, Internal Metric Thread, Internal Unified Thread, NoGo Gage

Does This Make my Buttress Look Big? Buttress Threads are Designed to Support or Reinforce.

Does This Make my Buttress Look Big?

The next time you unscrew the cap from your tube of toothpaste, take a look at the threads. They are quite likely Buttress threads. Have you used an adjustable wrench lately? Look at the thumb-screw. Buttress! All this time, right under your nose, was a thread-form that most people think, or know very little about.


Synonyms for "buttress" include; strengthen, reinforce, fortify, and support. The unique geometry of a buttress thread-form fulfills that requirement.

Tags: Buttress, Buttress Threads, Threads to Reinforce, Threads to Support