The Weldon Shank: Why It Is the Annular Cutter Standard
The shank is what couples an annular cutter to the machine, and for mag-drill cutters the Weldon shank is the global de-facto standard. It is a plain cylindrical shaft with one or two flats milled at 90 degrees; the magnetic drill's arbor has side set screws (grub screws) that clamp onto those flats to transmit torque and stop the cutter slipping. Named after the Weldon Tool Company, it fits the large majority of magnetic drilling machines in service worldwide.
For a sourcing program this matters more than any performance spec, because the shank is a binary compatibility question — a cutter with the wrong shank does not run slower, it does not mount. Leading a distributor catalogue with the Weldon standard covers the broadest installed base with a single SKU per size.
Weldon Shank Sizes We Supply
| Spec | 19.05mm (3/4") Weldon | 31.75mm (1-1/4") Weldon |
|---|---|---|
| Cutter diameter | Ø12–60mm (volume range) | Above ~Ø60mm (large diameters) |
| Flats | Two flats at 90° | Two flats at 90° |
| Grades available | HSS (M2), M42 cobalt, TCT carbide | HSS (M2), TCT carbide |
| Cutting depths | 25 / 50mm (HSS, cobalt); 35 / 50 / 100mm (TCT) | 50 / 100mm |
| Machine fit | Majority of mag drills worldwide | Heavy mag drills with 1-1/4" arbor |
| Pilot pin | Included, matched to depth | Included, matched to depth |
All Three Grades on the Weldon Standard
Shank and grade are separate decisions: the Weldon shank handles compatibility, the grade handles the steel you cut. We supply the full grade range on Weldon shanks so a distributor can match any job from one shank standard:
- HSS (M2): the volume line for mild and structural steel; TiN-coated, resharpenable.
- M42 cobalt: 8% cobalt for stainless, duplex, and high-tensile steel where HSS burns the edge.
- TCT carbide: brazed tungsten-carbide teeth for hardened, abrasive, and rail steel, and high-feed production.
See the grade decision guide for which to stock, and the shank-types guide for the full compatibility matrix.
Procurement Risk: What Goes Wrong with Shank Sourcing
Wrong Shank for the Machine Base
A batch of cutters that do not fit the customer's mag drill is unsaleable. Confirm the machine takes Weldon before ordering.
Out-of-Spec Flat Geometry
Flats ground off-position or off-depth let the cutter slip under the set screw — runout, oversize holes, and stalled cuts.
Missing or Mismatched Pilot Pin
The pin is depth-specific. A 50mm cutter shipped with a 25mm pin will not eject the slug — the cut jams on the second hole.
Over-Splitting into Proprietary Shanks
Stocking Nitto or QuickIN lines without a real machine base in the channel just multiplies SKUs and MOQ for no sales.
Program Structure for Distributors
- Base line: Weldon 19.05mm HSS, Ø12–32mm bolt-hole range, 25 / 50mm depths — the volume mover.
- Grade upsell: add M42 cobalt and TCT carbide on the same Weldon shank for stainless and hardened-steel customers.
- Large diameter: Weldon 31.75mm for Ø60mm+ cutters where the bigger shank is required.
- Accessories: pilot pins and arbors as consumable lines; quick-change adapters for drill-press users.
- Private label: branded tubes, printed boxes, set cases, laser engraving, and master-carton design.
Source Weldon Shank Annular Cutters
Tell us the shank size (3/4" or 1-1/4"), grade lines (HSS / M42 cobalt / TCT), diameter range, and cutting depth. We respond with a spec sheet, matched pilot-pin plan, and sample availability.
Request Annular Cutter Quote