Antique Machine Tool Tapers

From time to time, on this site, there have been questions asked as to what taper was used on various antique lathes.
I found this article in an 1885 American Machinist Magazine.
American Machinist had sent out a question to machine tool makers of the day asking what taper they used for lathes and drilling machines.
54 makers responded.

"Taper for Lathe Spindles and Drill Shanks", second column, pages 2 & 3.

American machinist. v.8 1885. - Full View | HathiTrust Digital Library | HathiTrust Digital Library

You can download single pages, either pdf or jpeg.

Rob

I will add the tapers used by Hardinge Brothers, Chicago, IL circa 1915. The "Cataract" tailstock taper was probably inherited from Cataract Tool and Optical Co. of Buffalo, NY, whose lathe products were bought by Hardinge about 1903.

Larry

Ed Battison called any oddball taper an "American" taper. I later found reference to this in the 1880 Census report. Report on power and machinery employed in manufactures, ... c.1. - Full View | HathiTrust Digital Library | HathiTrust Digital Library

"American" taper reports to be 9/16 per foot, Morse Taper at 5/8". My Flather No. 1 (does that number mean anything?) seems to be something else entirely? Proprietary perhaps?

I see Flather was a respondent to the survey and THEN reported "American Taper" and they were careful to specify 9/16" to the foot.

I will check Flather No. 1 and report back.

Joe in NH

Seems to be no Rivett or predecessor company in the list. The actual Rivett taper I have never seen any numbers for, other than what has been measured from existing parts. There is a drawing, but it references a tool.

Most folks seem to make a new T/S ram set up for MT2.

Joe in NH said:

I will check Flather No. 1 and report back.

Click to expand...

The Flather center is running about 0.625 (5/8") per foot. Certainly not the 0.562 of the 9/16 "American" Taper.

The diameter of the taper overall is larger than a No.3 Morse - a No. 3 taper adapter gets "swallowed up" by the Flather tailstock quill - and the taper eject feature (crank the quill all the way to the right) works to remove the Flather center - but does not touch a Morse No. 3.

So the Flather center, including its "shoulders" to catch a removal fork (No thru hole or drift hole), is probably original and unmolested. And the Flather taper is not the significantly larger Morse No. 4

So on this one, admittedly an early Flather, your mileage may vary. Proprietary existed for a reason.

Joe in NH

The Legend About the Morse Tapers

This looks like a good place to say that I've heard an unverified legend that the Morse Tapers were all supposed to be the same taper per foot, but they ended up the way they are because a set of gages provided to a U.S. government arsenal by Morse was defective. For some reason, Morse felt they had to provide product to Uncle Sam which matched the gages they'd sent, rather than recall the gages.

The Morse Tapers lack mathematical consistency. This is the only remotely plausible explanation I've seen for that.

Can anybody show me an at least semi-authoritative, at least semi-contemporary reference for this legend?

John Ruth
Who thinks Morse erred and became a widespread standard, while Jarno got it right but languished in relative obscurity!

This article talks about the errors in the first gages for Morse. It sounds like Morse was making their tapers and a few years later in 1871 made gages which fit the tapers that they were already producing so the errors of early manufacturing ended up as the standards.
American machinist. vol.19 (1896). - Full View | HathiTrust Digital Library | HathiTrust Digital Library

L Vanice said:

I will add the tapers used by Hardinge Brothers, Chicago, IL circa 1915. The "Cataract" tailstock taper was probably inherited from Cataract Tool and Optical Co. of Buffalo, NY, whose lathe products were bought by Hardinge about 1903.

Larry

Click to expand...

I had always wondered who was using B&S No.8 taper.
I don't think B&S ever used it on any of their mills.
I see quite a few old No.8 reamers for sale on ebay.

I have two sets of male B&S taper gauges, from No.1 to No.12, made by B&S and the female gauges from No.5 to No.11.
I also have the roughing and finishing reamers.
I also have the Morse taper gauges from No.0 to No.7, in both male and female, made by Morse Twist Drill.
I also have a very old(with the early marking)set of Morse gauges from No.1 to No.6, made by Morse Twist Drill.
I also have the Morse reamers from No.0 to No.6.

In the articles it said Morse made two sets of gauges around 1871. One for use in the shop and one kept under lock and key for reference.
I wonder what happened to those sets after the Morse auction.

Rob

The "American Taper" is a MT4 1/2. At .625 per foot. No tooling was made for it, It seemed to be used for spindle taper Angles, and centers.
So many times guys confuse Taper angle with Tapered tool size. They go out and buy a MT4.5 center, and it falls into the lathe spindle. That spindle has a MT 4.5 angle but NOT a MT4.5 size.

South bend to be a bit different, if they said a MT3 was used in the headstock, the taper ANGLE of the spindle adapter was that of an MT3, but of course NOT the Size. I do not know if every SB was that way,

A few years ago I made spindle adapters for Rockwell/Delta lathes. They had the Angle of an MT4.5 in the spindle bore, but .035 larger diameter. So you were forced to buy their adapter I guess.

SouthBendModel34 said:

This looks like a good place to say that I've heard an unverified legend that the Morse Tapers were all supposed to be the same taper per foot, but they ended up the way they are because a set of gages provided to a U.S. government arsenal by Morse was defective. For some reason, Morse felt they had to provide product to Uncle Sam which matched the gages they'd sent, rather than recall the gages.

The Morse Tapers lack mathematical consistency. This is the only remotely plausible explanation I've seen for that.

Can anybody show me an at least semi-authoritative, at least semi-contemporary reference for this legend?

John Ruth
Who thinks Morse erred and became a widespread standard, while Jarno got it right but languished in relative obscurity!

Click to expand...

I will try to address this and Joe's reference to the "American Taper".
I have always been interested in early tapers for machine tools, especially milling and drilling machines.
One thing you have to understand is what the taper is being used for, ie, for milling, drilling or lathe centers.
You also have to remember the time frame for Morse tapers(mid 1860's to early 1870) and the machine tools and gauging equipment available at that time.
I would not say that Morse erred and Jarno got it right. Jarno came well after Morse when gauging equipment was far better.
The "unverified legend" is not entirely correct.

A few of us, on the PM, email each other on old machine tools. Last night I sent out a lot on Morse with links. enginebill has posted one of those links.
I was doing research on Morse again and the Manhattan Fire-Arms Co. taper. Still trying to find the large and small end dimensions for the Manhattan taper, which would become the American taper.

First here is a link to an American Machinist article in 1884 showing Morse taper dimensions, which they got from Morse.

American machinist. v.7 1884. - Full View | HathiTrust Digital Library | HathiTrust Digital Library

At that time they believed these were measured correctly, but of course were not.
This spurred some more articles in 1885 American Machinist.

Letter to American Machinist from George Stetson, Superintendent of Morse Twist Drill.
Note that this letter also explains how the No.6 taper came about.

American machinist. v.8 1885. - Full View | HathiTrust Digital Library | HathiTrust Digital Library

Another one from 1885.

American machinist. v.8 1885. - Full View | HathiTrust Digital Library | HathiTrust Digital Library

One more from 1885, with a response from George Stetson.

American machinist. v.8 1885. - Full View | HathiTrust Digital Library | HathiTrust Digital Library

From 1896 when Morse found they had not measured the tapers correctly back in the 1870's.

American machinist. vol.19 (1896). - Full View | HathiTrust Digital Library | HathiTrust Digital Library

Morse knew about the errors in the taper per foot between the tapers back in the early 1880's.
They cited the gauging equipment and machines at the time for the error.
They thought about changing it but it was in such widespread use that they decided to leave it alone.
They thought that changing it would bring about more confusion.
This was from an article in a British publication by George Stetson.

Most people today believe that all of the Morse tapers were to be 5/8" to the foot, but this is wrong.
In the above articles George Stetson said the 5/8" had been departed from.
There was a problem then, which we still have today, called pull out.
This is when a drill bit comes thru the other side of the hole being drilled.
It likes to grab and pull. If the work piece is not clamped, it likes to pull the work up.
If the work piece is clamped, then the drill bit likes to pull down and if there is any slack in the drill spindle it will pull even harder.
This sometimes results in the drill bit pulling out of the Morse socket.
This was a big problem on the smaller drill bits, but not as much on the larger drill bits.
They found out that by making the taper per foot less than 5/8", that it would greatly reduce the pull out.
Morse decided to make the smaller tapers(1,2,3) .600 taper per foot and keep the larger tapers(4 & 5)at 5/8". At that time 0, 6 & 7 did not exist.

Morse had a competitor in the early years for both drill bits and the taper used for drill bits.
This was the Manhattan Fire-Arms Co. They made guns and drill bits. Their taper was called the "Manhattan Taper".
Later, Manhattan would reorganize as the American Standard Tool Co. Still making guns and drill bits.
Their taper would then be known as the "American Standard Taper", which would be shortened to the "American Taper".
Manhattan had the same problem with pull out. They decided to use 9/16" taper per foot on their smaller tapers and 5/8" taper per foot on their larger tapers.
This will explain the taper on Joe's lathe.

Stephen Morse went to work for the American Standard Tool Co. after he left Morse Twist Drill & Machine Co.
Some of his patents are assigned to the American Standard Tool Co.
Eventually Morse Twist Drill would buy the drill business of the American Standard Tool Co.
Morse continued to offer the "American Taper" for awhile and then phased it out.
Stephen Morse would go on to start an elevator company in Philadelphia. He has many patents for elevators.
Stephen Morse retired from his elevator company in 1891 and died in 1899.

Here is a picture I have of the Morse Twist Drill employees in the 1880's.
Also an ad showing Stephen Morse working for American Standard Tool, and elevator ads.

Rob

Although not directly relevant in a discussion about taper standards, I was surprised to learn that taper-shank tooling was in use over 200 years ago.

I was recently reading ‘James Watt’ by H. W. Dickinson, 1935. Watt started developing machines for copying sculptures, and in 1809 he ordered some ‘drills made in steel frames of peculiar construction to turn with great velocity and without a shake’ from ‘a skilful mechanic named Green in Manchester’.

Watt wrote ‘You will see that instead of putting the drills in by screws, they are put in by a taper which I find easier fitted & is I believe easier of execution by him [i.e. Mr. Green].’

It is not clear form the text whether it was Watt or Green who came up with the taper, but a drawing by Watt dated 1811 shows a tapered shank spade drill in a tapered spindle. The drill shank taper is 1 in 6, and the drill is secured by a screw thread, so the taper is there to provide good location, not to drive the drill by friction.

Green may well have been Edward Green, who had a business in Manchester making lathes, clockmaker’s gear-cutting machines and other tools in the early 1800s.

Asquith said:

It is not clear form the text whether it was Watt or Green who came up with the taper, but a drawing by Watt dated 1811 shows a tapered shank spade drill in a tapered spindle. The drill shank taper is 1 in 6, and the drill is secured by a screw thread, so the taper is there to provide good location, not to drive the drill by friction.

Click to expand...

In my research on tapers I came across a reference to a Samuel Colt from England(not the Samuel Colt, gun maker from the US).
This Samuel Colt was also into firearms. It gave a patent number, for a patent he had on machine or tooling tapers.
I did not try very hard but could not find a drawing of the patent.

Rob

Rob... it is likely the same Samuel Colt. He operated a London factory from 1854 to 1856 and held a number of British patents, many of which led to long and tortuous litigation in the UK because British gunmakers doubted the validity (quite rightly) of some of his his claims... these included machines and machine tools - in fact, they may have been the majority of his patents. While today's Colt enthusiasts tend to describe him as a "super salesman", he was more the type to bribe anyone and everyone who might be of use to him. This often included the gift of sumptous decorated Colt revolvers. Colt never did anything unless he expected it to pay off.

During the Crimean War, while he had a factory in London, he was also trying to sell his revolvers to the Russians and even brought a Russian officer to England, disguised as one of his servants, during the war.

99Panhard said:

Rob... it is likely the same Samuel Colt. He operated a London factory from 1854 to 1856 and held a number of British patents

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When I first saw the reference I thought it was the same Colt. I thought, how many Samuel Colt's are there that are involved in fire arms at that time period.
When I saw he was in England I then thought it was not the same Colt. I did not know he had a London factory.
I would like to find the drawing for the taper patent. It appears he did not do a US patent on it. At least I have not found it.

Rob

Confirmation of Rob's "Manhattan Firearms" comes from an interesting application - ball & socket joints used in artificial hip replacement. One hundred and fifty years of history of the Morse taper: from Stephen A. Morse in 1864 to complications related to modularity in hip arthroplasty

Differences with his board caused Morse to resign in 1868. Philadelphia’s 1877 Centennial Exhibition showcased the first exhibition of Morse tools. Morse products gained an international reputation for quality and were sold throughout the United States and in England, Russia and Germany. In the latter part of the 19th century, the company began a pattern of acquisition which resulted in enormous growth. Morse took over the Manhattan Fire Arms Company of Newark, New Jersey and the American Standard Tool Company of Danbury, Connecticut. Morse also acquired the Beach chuck patent of the Meridan Tool Company, Meridan, Connecticut, and the Schofield Patent Grinding Line, helping to ensure accuracy in drill grinding. In 1874, Morse purchased the machinery, patents and stock of the New York Tap and Die Company of Bridgeport, Connecticut. In 1897, Morse purchased the T & B Tool Company. T & B’s machines, used in the manufacture of constant angle twist drills, were designed by a former Morse employee who had gone into business for himself and were built by Pratt and Whitney. Entering the 20th century, Morse developed a grinding machine used in the manufacture of drills. Until the beginning of World War I, the company marketed a line of plain and universal grinders. Business continued to grow between the wars, and during World War II, Morse output increased four to five times normal production to contribute to the war effort. In the years since World War II, Morse has operated under the ownership of a number of companies, including Gulf and Western. The current owners, a group of American investors, purchased the company from a Scottish manufacturing concern, and are committed to upholding the Morse reputation for high-quality, American-made cutting tools. Today, Morse inventories over 25,000 varieties of cutting tools to serve our nation’s marketplace. Imagination, technological innovation and insistence on quality are built into every Morse product. And at Morse, our people wouldn’t have it any other way.

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Joe in NH

Apparently, with the surgical folks, ALL tapers are considered to be "Morse" tapers. We consider :Morse" to be one specific form of taper, and recognize others. The surgical versions seem to be much larger included angle than Morse, B & S, or the like. Maybe they are still self-holding, but at up to 15 deg, I wonder about that.

The problem is that British patent numbers do not run consecutively like US ones so you need both the patent number and the year. I believe at the time they started the numbers over each year but I can be corrected on that. If you can find those, I think I can find it. The year isn't all that important because it will be between about 1852 and 1858.

Colt used a lot of specially designed machine tools, largely invented by Elihu Root, his resident mechanical genius... although Colt liked taking credit for everything that came out of his factory. It would make sense that he would patent new ideas, or even old ones if there wasn't already a British patent on them. As far as a us patent, try searching on Root's name.

Also, Manhattan firearms produced a percussion revolver similar to Colt's and was put out of the firearms business by a patent infringement suit. I did not know they also produced machine tools so this has been very informative.

jp

I found a little on Samuel Colt's British patent. No.861, April 12, 1854. "Machinery for Cutting or Shaping Metals".
It looks like it was a machine that had a revolving wheel, with 10 powered spindles, that held cutting tools.
It looks like a large Burgmaster Turret Drill. It looks like it used a taper to hold tooling.
I found a drawing (that I could not download) of a taper shank arbor with a compression chuck holding a drill bit.
This drawing is purported to be from the patent.
I also found a very small picture of the machine or what I think is the machine. Without the patent drawing I am not sure of the above info.

Joe's info in post #15, in part, was taken from info on Morse's site.
They got it wrong about Morse buying both Manhattan Fire-Arms and American Standard Tool.
99Panhard shows the problem Manhattan had.
Weather they went out of business and were purchased by the newly formed American Standard Tool or reorganized as American Standard Tool is something 99Panhard can probably supply more info on.
I think some of the original owners of Manhattan were also involved in American Standard Tool.
The American Standard Tool Co. is what Morse would purchase and just the drill making part.

Some of the machine tools Manhattan made were for milling the flutes of twist drills.
The machine tools they made were special machines for making their twist drills.
Most if not all of these machines were patented by Andrew R. Arnold, who worked for Manhattan. These patents were assigned to Manhattan.
These were in the 1860's. One of his patents was assigned to American Standard Tool in 1869.

Sorry for the small size of the Colt machine picture but it was very small to start.

Rob

I've seen a much larger version of that photo and I believe it is one of Root's machines built at the hartford factory. Colt equipped the London factory with machines from Hartford and it would not surprise me if he took out British patents on them. In fact, he was setting up a factory in the one country that had the capacity to copy his machines so that was probably a prudent move. I don't know if he had an American patent on the same machine but I know where to look... I'll report back after I've been into the office - which may not be until Monday now.

jp

It turns out that the readily accessible British patents, in the Natinal Archives, end in 1852. For 1854 you have to go to the Intellectual Property Office in the British Library. I have a readers card for the National Archives and used to have one for the British Library - they aren't difficult to get but you do have to go there. As luck would have it, I will be in the UK next month although I do not know if I'll have the time to go up to London. If I do get a chance, I will stop at the Library and see if I can't get a copy of that patent.

jp