Help identify this taper plz

[Piero]

Hi guys

Jacobs Drill chuck No34, no taper markings,

A strange D66 stamped on it but I have no idea what that means

You would think it would be a jacobs taper but I can't match it to one

Anyone have a idea plz

 

[Seadog]

I'd say it's JT6.

 

[Piero]

One new finding

The taper appears cut short on both ends as the drill chuck hole has a depth well in excess of an inch

 

[badabec]

What Is A Jacobs Taper? | Chuck Mounting Basics

A Jacobs taper is a self-holding cone that presses a drill chuck onto an arbor; JT sizes define the small and large diameters that create the grip. Jacobs Taper Meaning And Where It Fits The Jacobs taper is a short, shallow cone used to seat a drill chuck on a matching arbor. One side carries […]

thetoolstrunk.com

 

[Pete.]

I'd say it's JT6.

I'd say the same. It's not a B18 the angle is too steep.