Insert-Pro CNC Router Bits

Insert-Pro CNC Router Bits with Replaceable Carbide Knives

Insert-Pro router bits pair a precision-machined bit body with replaceable solid carbide knives locked in place by a set screw. When a cutting edge dulls, you rotate the knife to expose a fresh edge; when both edges are spent, you drop in a new insert. There is no resharpening, no change to cutter geometry over the life of the tool, and no need to buy a whole new bit, which makes Insert-Pro tooling an economical choice for production CNC shops and serious makers alike.

The V-groove bits are built for sign making, lettering, engraving and decorative routing. The 3" 90° Insert-Pro V-groove bit (94-302) delivers 1-1/2" of cutting height on a 3/4" shank for deep, wide grooves, while the 2-5/8" 90° V-groove bit (94-303) offers 1-9/32" of cutting height in a slightly more compact profile. For broader, shallower V-cuts and lettering, the 120° Insert-Pro V-bit (94-301) runs two carbide knives on a 1/2" shank.

For folded box and cabinet construction, the 91° Insert-Pro miter-fold bit (94-300) cuts a clean V-groove nearly through the panel so it can be folded into a tight mitered corner. Its 2-5/8" diameter and 1-5/16" cutting height handle thick sheet goods, and the precisely ground knife minimizes buildup at the point of the cut for consistent, repeatable folds.

Keeping your machine true is just as important as cutting parts. The 2-1/2" Insert-Pro spoilboard surfacing and rabbeting bit (94-201) uses a 2+2 design, two shear-angle cutting knives plus two bottom scoring inserts, to resurface spoilboards, flatten panels and cut clean rabbet shoulders. The 1-1/2" Insert-Pro mini surfacing bit (94-200) is sized for smaller machines and square-edge work. Both run on a 1/2" shank and work in CNC machines, handheld routers, router tables and router sleds.

Choosing the Right Insert-Pro Bit

Choose a 90° V-groove bit for classic sign lettering and decorative grooves, the 120° V-bit for wider, shallower cuts, the 91° miter-fold bit for folded panel joinery, and a surfacing bit for spoilboard maintenance and flattening. Replacement carbide knives are sold by bit part number, such as the 94-302 replacement knife, so keep a spare on hand to avoid downtime. Explore the full CNC router bits collection, browse solid carbide spiral router bits for profiling and pocketing, or shop the complete router bits library.

Frequently Asked Questions

What is an Insert-Pro router bit?

An Insert-Pro bit uses replaceable solid carbide knives held in the bit body by a locking screw. When an edge wears, you rotate or replace the knife and keep the bit, with no resharpening.

How do I know when to rotate or replace the knife?

Rotate the knife when cut quality drops: fuzzing, burning, or rougher edges. Most V-groove and miter-fold knives have two cutting edges. Once both are dull, install a new insert.

Which replacement knife fits my bit?

Replacement knives are matched to the bit’s part number. For example, the 94-302 uses knife 94-302.CIK.1. The 94-201 surfacing bit uses two knife types, CIK-057A and 94-201.CIK.2. The required knife is listed in each bit’s specifications.

What’s the difference between the 90° and 120° V-groove bits?

A 90° bit cuts a deeper, steeper groove, which is the classic look for sign lettering and decorative grooves. A 120° bit cuts a wider, shallower V, which suits broad chamfers and larger lettering at a lower depth.

What is a miter-fold bit used for?

A miter-fold bit cuts a V-groove almost all the way through a panel, leaving the face intact so the panel folds into a mitered corner. It’s commonly used for boxes, cabinet cases, and display pieces. The 94-300 has a 91° angle.

Can I use the spoilboard surfacing bits in a handheld router or router sled?

Yes. The 94-200 and 94-201 have 1/2" shanks and are rated for CNC machines, handheld routers, router tables, and router sleds. The V-groove and miter-fold bits are designed for CNC routers.

What shank sizes are available?

The 94-301, 94-200, and 94-201 have 1/2" shanks. The 94-302, 94-303, and 94-300 have 3/4" shanks, so your spindle needs a 3/4" collet.

What RPM should I run these bits at?

Max RPM is 18,000 for the V-groove and miter-fold bits, 19,000 for the 94-201, and 24,000 for the 94-200. Larger-diameter bits need lower speeds, so always stay at or below the rated maximum.

What materials can Insert-Pro bits cut?

They’re designed for wood, MDF/HDF, plywood and veneered panels, melamine, laminates, plastics and PVC, solid surface, sign board, composites, and foam.

Are Insert-Pro bits covered by a quality guarantee?

Yes. All Infinity Tools Insert-Pro bits are backed by our 100% Satisfaction Guarantee. Contact us if a bit doesn’t perform as described.