Iscar 7090778 Indexable Turning Shim Issn Square Insert

Product Description

The ISCAR 7090778 is an ISSN-style shim designed for indexable turning toolholders. Shims seat beneath the cutting insert in the toolholder pocket, maintaining correct insert height, protecting the pocket floor from damage, and ensuring repeatable positioning across insert changes. This shim is configured for negative-rake square inserts with a 0.5 inch (1/2 inch) inscribed circle. It is installed by machinists and toolroom technicians working on CNC lathes and manual turning centers where indexable tooling is used in production or maintenance machining operations.

This shim is suited for negative-rake turning applications using square indexable inserts. It is intended for use in toolholders with MSSNR and MSDNN-style pocket configurations. Typical applications include external turning operations on CNC and manual lathes in job shop, production, and maintenance machining environments. Sold individually, making it practical for single-pocket replacement without committing to bulk quantities.

Key Features

• ISSN shim style for negative-rake square insert seating
• 0.5 inch inscribed circle matches standard 1/2 inch square indexable inserts
• Protects toolholder pocket floor from insert wear and impact damage
• Ensures consistent insert height and repeatable tool positioning
• Compatible with MSSNR and MSDNN toolholder pocket styles
• Sold in single-unit quantity for targeted replacement

Compatibility

Compatible with the following complete toolholder configurations as stated by the manufacturer: MSDNN 16-4 and MSSNR 16-4. Designed for use with negative-rake square indexable inserts with a 0.5 inch inscribed circle in MSSNR-style toolholder pockets.

Installation Notes

Installation should be performed by a qualified machinist or toolroom technician with the machine powered down, spindle locked, and all motion axes secured before accessing the toolholder pocket. The shim must be seated flat and flush in the pocket before placing the insert to prevent rocking or uneven clamping force. Inspect the pocket floor and shim contact surfaces for debris or damage before assembly. Follow the toolholder manufacturer torque guidance for the insert clamping screw.