Klein Tools 31850 3/4-in Carbide Hole Cutter - Heavy-Duty Cutting

In this review of the Klein Tools 31850 hole cutter, the bottom line is simple: this tool is aimed at tradespeople and fabricators who need a reliable cutter for clean holes in sheet metal. The cutter's single biggest selling point is its premium carbide construction, which delivers fast, clean cuts through stainless steel, mild steel, iron, copper and brass up to 3/16-in thick. For anyone who regularly punches holes for conduit or pipe work, the 3/4-in size and built-in features make it a focused, practical choice.

Key Features

• Premium carbide hole cutter: The carbide cutting edge is designed to stay sharp and resist wear, giving longer service life when cutting metal sheets.
• Heavy-duty cutting: Cuts clean holes through stainless steel, mild steel, iron, copper and brass up to 3/16-in thick for common shop and field tasks.
• Split point pilot drill: The split point pilot helps prevent bit wandering so holes start accurately with less walking on sheet surfaces.
• Built-in flange stops: Flange stops reduce the chance of over-drilling into backing surfaces when working on thin sheet metal.
• Replacement pilot compatible: Uses a replaceable pilot bit (Cat. No. 31874) so you can renew the pilot without replacing the whole cutter.
• Conduit and pipe sizing: Sized for 3/4-in conduit and pipe applications, matching typical electrical and mechanical routing needs.

Who It's For

The 31850 is best for electricians, HVAC techs, metal fabricators and general contractors who cut holes in metal for conduit, pipe and fittings and who need a cutter that performs in harder materials like stainless steel. Its focused 3/4-in size makes it ideal when that specific opening is required rather than a general-purpose hole-saw set.

Those who should look elsewhere include casual DIYers who rarely cut metal and would be better served by a multi-size hole-saw kit, and users who need very large or adjustable hole sizes-this is a single-size, specialty cutter rather than a multi-diameter system.

Pros & Cons

Pros

• Consistently cuts clean holes in stainless and mild steel thanks to the carbide blade.
• Durable construction and quick cutting speed make it efficient on job sites.
• Split point pilot and flange stops provide better accuracy and controlled drilling.
• Compatible replacement pilot keeps maintenance costs down.

Cons

• Pilot bit durability is mixed in user experience, with some reports of pilot breakage under heavy use.
• Single fixed size limits flexibility if you need multiple hole diameters frequently.

Specifications

Brand	KLEIN TOOLS
Model	31850
Cutting diameter	3/4-in
Material compatibility	Stainless steel, mild steel, iron, copper, brass
Maximum sheet thickness	3/16-in (0.5 cm)
Pilot bit	Split point pilot, replacement pilot compatible (31874)
Application	3/4-in conduit and pipe openings

Our Verdict

The Klein Tools 31850 is a specialised, well-built carbide hole cutter that delivers clean, fast holes in a range of metals and is particularly useful for pros who cut conduit and pipe openings. It represents good value for someone who needs reliable metal-cutting performance in the 3/4-in size, though occasional pilot replacement should be expected under heavy use.

Frequently Asked Questions

Can this cutter handle stainless steel?
Yes, it is designed to cut stainless steel sheets up to 3/16-in thick with a carbide edge for durability.

Is the pilot drill replaceable?
Yes, the pilot is a split point design and is compatible with a replacement pilot bit (Cat. No. 31874).

What size conduit is this for?
It is intended for 3/4-in conduit and pipe sizes commonly used in electrical and mechanical work.