When you're shopping tooling cutters and abrasives, the first decision on an end mill set isn't the coating-it's the cutting geometry and diameter your jobs actually demand. This head-to-head pairs a 12mm corner radius cutter set from SGS (Kyocera SGS Precision Tools) with a 1/4-inch four-flute long carbide end mill set from ZIMI. The list prices sit far apart: $229.00 for the SGS set versus $49.99 for the ZIMI set. That gap points to different work.
Quick verdict: If you need a 12mm cutter that leaves a controlled 1.0mm radius on the corner, the SGS set is the purpose-built answer. If you need a compact 1/4-inch square end mill for shallow grooves, profile milling, and steel work up to HRC45, the ZIMI set is a practical choice.
| Feature | SGS 12mm Corner Radius | ZIMI 1/4-inch 4-Flute Long |
| List price | USD 229.00 | USD 49.99 |
| Pack size | 5 pieces | 5 pieces |
| Cutting diameter | 12 mm / 0.4724" | 1/4-inch |
| End style | Corner radius (1.0 mm radius) | Square end |
| Flutes | 6 | 4 |
| Coating | TA coated | TiAlN coated |
| Length of cut | 15 mm | 0.708" |
| Country of origin | United States | China |
Where each product wins: The SGS set wins for larger-diameter radiused work. The 12mm cutting diameter and 1.0mm corner radius let you machine a profile with a built-in radius, and the six flutes offer a different cutting characteristic than a four-flute tool. The ZIMI set wins for compact, general-purpose milling. The 1/4-inch square end reaches tighter spaces, and its four-flute, long-format body is aimed at shallow groove and profile passes. They're not direct substitutes: the geometric difference drives the decision.
SGS 12mm Corner Radius 6FL Carbide End Mill
This five-piece set from Kyocera SGS Precision Tools is built around a 12mm solid carbide body with a 1.0mm corner radius. Six flutes distribute the load, and the 15mm length of cut makes it a finishing-oriented tool for radiused slots and profiles rather than deep plunge work. The tools arrive in original SGS plastic tubes, and the shank is a standard 1/2 inch. Choose it when your drawing calls for a precise corner radius and you want the geometry locked in on every pass. The limitation is the cutting length: at 15mm, it's not suited to deep-slotting jobs, so keep that in mind if your operations go deeper than that.
ZIMI 1/4-inch 4-Flute Long Carbide End Mill
The ZIMI five-pack brings a 1/4-inch square end with four flutes, described as a long carbide end mill for shallow grooves, profile milling, and precision machining. The AlTiN coating is specified for heat resistance, hardness, and oxidation resistance, and the tooling is aimed at carbon steel, alloy steel, pre-hardened steel, and cast iron up to HRC45. Choose it when you want a smaller square cutter for flexible general work and you don't need a corner radius. The limitation is the hardness ceiling: it's not listed for material above HRC45, so leave it on the shelf for anything significantly harder.
Final choice by use case: Go with the SGS 12mm set when your work is defined by a 12mm radiused profile and you want a six-flute finish. Go with the ZIMI 1/4-inch set for general-purpose square-end milling in steels up to HRC45 and when you want the lower list price. Match the end mill to the feature you're cutting, and the right set will follow.
