View Full Version : Origins of the "L" tapers

09-08-2006, 03:47 PM
Just curious, but what are the origins of the "L" spindle tapers? Does "L" stand for something?

09-08-2006, 04:36 PM
Does "L" stand for something?

The "L" means "Long Series" taper.

There are three ASA standard lathe chuck tapers: L-series (long taper), A-series (short taper), and D-series (Cam Lock)

Each one of the series comes in a variety of sizes. The L-series comes in L-00, L-0, L-1 and L-2. The L-00 is the smallest.

09-08-2006, 04:40 PM
I thought I had seen "L" as "Long", but then I saw a dog driver labeled as a "Lablond Taper", and I wasn't so sure. Thanks for the refresher and confirmation. :D

John Stevenson
09-08-2006, 04:57 PM
Propriatry taper invented by Lodge and Shipley.


09-08-2006, 05:09 PM
So are you saying the "L" (aka "Long") tapers started with a proprietary L&S, but then got adopted by many others like Clausing and Rockwell among others so that it became something of a standard? Or is that in reference to the so-called “Lablond Taper”?

09-08-2006, 05:09 PM
Propriatry taper invented by Lodge and Shipley.

The original Lodge & Shipley lathes shipped with one of two L-tapers: the 12" - 20" lathes shipped with what's now called the L-1 taper, and the 22" - 30" lathes shipped with what's now called the L-2 taper.

If you've ever seen an L-1, it's massive -- I've love to see a 12" lathe with an L-1 spindle :)

Somewhere during the standardization of the taper series, the ASA added the L-00 and L-0 tapers, which are commonly seen on 12" and up toolroom lathes (Rockwell, Clausing, Standard Modern,...)

09-08-2006, 05:17 PM
By the way BadDog, Cushman has a great page with pictures of the various lathe chuck tapers:

Type L Long Taper Key Drive (http://www.workholding.com/cushtypl.htm)

Rich Carlstedt
09-08-2006, 05:38 PM
I had a LeBlond lathe years ago that was made in 1943
It had a L0 taper . but the bore had a taper that did no match anything I had as a standard like Morse 4, 4 1/2, or a 5
I called the factory and talked to an old time Engineer.
he said that LeBlond would do custom tapers back then (on the Bore)
and an adapter would come with the lathe for a center..ie MT 4 etc.
He said they liked to use .5 or .625 per foot, but would meet customers demand for a spindle tapered bore "Mouth" diameter.(AND TAPER!)
I wonder if this is what you are reffering to ?


09-08-2006, 07:29 PM
No, I think he was talking about the actual outer spindle taper since this was in reference to a chuck adapter.