Need Jacobs chuck keys - Numbering system confusion

[Sheriff Roscoe]

Looking for two Jacobs chuck keys but their numbering system has me confused:

1st chuck: 633C / 33 Taper / CAP 0-1/2
2nd chuck: 34-33-33 Taper / CAP 0-1/2in 0-13mm

Can someone explain the meaning of these numbers? And more importantly which chuck key I need for each?

Thanks guys!

 

[A_Pmech]

The first number is the chuck model number.

Jacobs has a table on their website listing key compatibility.

 

[Sheriff Roscoe]

Thanks AP. Didn't see it on their website but was able to find a chart elsewhere. Looks like a K3C key is what I'm after.

 

[A_Pmech]

Here's the chart I was thinking of:

http://www.jacobschuck.com/images/products/accessory.pdf

K3C looks correct per that chart for the 34-33, but the chart doesn't list the 633. Grr!

 

[zkling]

Just looked at mine it's a #3, has a ~.310" pilot. Those are collared chucks no? I'm not sure what the difference between a K3C and a K3 are.

The numbers are model / mount size and style / capacity range. As AP Mech said.