Gack Accessories

This Gack came with most, but not all of the original accessories. The accessory names come from the translated German advertisment.

Accessories with the machine

Gripping jaw device

A vice by any other name.

The jaws can be used directly on the table or on a swivel base. When the jaws are loose, they will rotate through a small angle to adapt to irregular work.

One of the jaws has a tilting face that grabs the work and pushes it down at the same time.

Vice jaws on the swivel base

Vice up close

Vice jaws on the table

Dividing head

The dividing head will take the collets or the X-Y coordinate chuck described later.

There are four dividing plates: 37-31-29, 39-27-23, 36-33-21, 20-19-17. See the dividing table.

Dividing head

Dividing head angle scale

Dividing head and tailstock

Dead center and driving center

Universal clamping device

This is a chuck for the dividing head with X-Y coordinate offsets. It has an adapter to take the collets and a faceplate which looks like it might have been shop-made by some previous owner.

Coordinate chuck

The maximum X or Y offsets are +- 1 inch.

Coordinate chuck showing offset


I've been told these are Schaublin collets.

Gack collet

Face view

Collet set

Measuring microscope

The scope has cross hairs and X-Y offset micrometer screws. It has a long focal length so it can be used on work held in the vice while the machine is running. Used with the coordinate chuck, you can form a radius anywhere on the work.

It is also great for tool-setting and aligning the tool to follow contours.

Measuring microscope

Finding center of rotation with the scope

Accessories I'd like to find

Optical projector

One of my tool-using friends identified the measuring microscope described above as a product of the Isoma Company. He sent me these EBay photos, which I'm guessing look show something similar to the projector missing from my Gack. If you've got one for sale, let me know!

Isoma projector 1

Isoma projector 2

Isoma projector 3