What Is The Correct Name For This Tool?

I think they were used by clockmakers and gunsmiths ,many years ago. I've seen them in pictures most are for fine threads , not to many have normal sizes we use today .
 
I do mechanical antique repairs and make parts,etc.. I actually use those threading dies,and early screw plates to make threads sometimes. Since threads were not made to set standards in the old days,you can adjust the diameter of your threads with this type of die.
 
Some of those odd threads were used on older machinery. Brown & Sharpe was great for that on their machines years ago. Not a single screw on their machines had a thread that wasn't special. That way they could charge high prices for screws when needed. Many places ended up re-tapping for standard screws to save money.
 
Billh50 said:
Some of those odd threads were used on older machinery. Brown & Sharpe was great for that on their machines years ago. Not a single screw on their machines had a thread that wasn't special. That way they could charge high prices for screws when needed. Many places ended up re-tapping for standard screws to save money.
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Personally, I think Brown & Sharpe had every right to set their own standards for threads; it was a time when there were no standards that were commonly accepted, and our standards that we use now, came along much later than when B&S were building some of the finest machinery made. I had a 1906 B&S #2 milling machine that I used in my business for about 30 years on a daily basis; at that time, the only non standard thread used on it was 1/2-14, rather than 13, and that at a time when the common standard was 1/2 - 12.
 
Actually there were standards back then. The NC and NF standards came about in mid 1860's.

Screw threads for fasteners were cut by hand but increasing demands deemed it necessary from them to be factory made. J and W Wyatt patented such a system in 1760. The lack of thread standardisation made fastener interchangeability problematical.

To overcome these problems Joseph Whitworth collected sample screws from a large number of British workshops and in 1841 put forward two proposals:
1. The angle the thread flanks should be standardised at 55 degrees.
2. The number of threads per inch should be standardised for various diameters.
His proposals became standard practice in Britain in the 1860's.

In 1864 in America, William Sellers independently proposed another standard based upon a 60 degree thread form and various thread pitches for different diameters. This became adopted as the U.S. Standard and subsequently developed into the American Standard Coarse Series (NC) and the Fine Series (NF). The thread form had flat roots and crests that made the screw easier to make than the Whitworth standard that has rounded roots and crests.

Around the same time metric thread standards were being adopted in continental Europe with a number of different thread flank angles being adopted. For example the German Loewenherz had a thread flank angle of 53 degrees 8 minutes and the Swiss Thury thread an angle of 47.5 degrees. The standard international metric thread eventually evolved from German and French metric standards being based upon a 60 degree flank angle with flat crests and rounded roots.
 
I am talking about 18th.C. mechanical devices,not 19th. C. things. I have an avid collector customer who only does 18th. C. items. And,I was in Col. Williamsburg for 40 years as musical instrument maker,then tool maker. So,it's wired into my DNA!!:)

Some of those very small threads I have to reproduce look like light bulb threads(knuckle threads) when magnified.
 
George I was not referring to your reply but to benmychree about the 1906 B&S miller. I do know that most threads prior to the standards were made mostly by hand and therefore of many different sizes and pitches.
 
I have a similar tool, with dies for 24, 32 and 36 tpi. It's cute.
It is not clear how you could cut a specified size (diameter) of thread since the dies would not be touching each other. But, it's cute.
 
wlwhittier said:
Hi...Noob here; first post.

I call this an adjustable die-plate. eBay search shows nothing remotely similar. This is beautifully made, and a pleasure to hold and fondle...I have another, smaller (European) version as well...but don't know what to call it so I can go scouting for more information on age, specific use, etc. View attachment 105020
As shown it's 9-5/8" long, 1-1/2" wide; the dies are 1/4" thick; weight is ~11-1/2 ounces. when I got it there was an accumulation of dried lubricant, shop soil, very minor surface rust (mostly at the V-faces & between the die sections) as well as fine shavings in all the relief grooves and threads. All better now.

When was 1/4-24 a popular thread? I haven't determined what the other five dies will cut.

Thanks for looking! wlw
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Multiple Thread Chaser I say.
 
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