Ever wondered how Bi-metal holesaws are made?
With Bi-metal holesaws, mean that the teeth are made from a hardened metal that’s different from what the rest of the cup is made from.
The bi-metal hole saw is “the workhorse of the industry,” and is used by many different trades, and so it needs to be able to cut holes in clean wood, nail-embedded wood, steel, aluminium, composites and plastics plus more!
Forming the Flat Blank
The hole saws start out as a coil of bi-metal flat stock with the teeth already formed. From the roll, the strip of metal goes into a straightener and then gets fed into their presses.
There are four different presses on the production line. One stamps the size markings onto the blank. Another cuts the slots for removing the plug. The last one cuts the strip into shorter lengths for bending into hole saws of the specified size. The fourth press isn’t used in production, it is used for prototyping — e.g. testing new types of slots.
The blank then gets heated red hot and then is fed into the hot forming machine. There, hot blank gets dropped in place between the cylindrical center die and the rear concave die.
First, the rear die pushes forward, to partially wrapping the hot blank around the cylinder. Then, the side dies come in to wrap the blank further around the cylinder. Finally, the front die completes the wrap around the cylinder.
The now round blank is removed and placed on a conveyor which moves through an air cooling tunnel.
From there, the round blank gets loaded into the welding station. It uses three robotic arms that work in concert to pull the round blank off the conveyor, weld the seam on the side, and weld the cap to the bottom.
Below you can see a closeup of one of the robotic arms placing a hole saw into a fixture to weld the seam.
- HSS Bi-Metal Construction
Holesaws feature a solid HSS body, with a precision, welded M42 Cobalt Bi-Metal strip for the cutting teeth. M42 Cobalt Bi-Metal is one of the hardest and toughest Bi-Metal formulations.
- Shark Gill Slug Removal Slots
Featuring a very unique angled slot design, that allows easy plug removal of different thicknesses of material with a standard screwdriver. The integrity of the holesaw HSS wall is critical to the lifetime and ability of the saw to cut a round hole. We have worked through many prototypes to get the best balance between large easy to use slots, and still maintaining a rigid wall strength.
- Unique Shark Tooth Grinding
These feature a unique grinding on the teeth which produce a sharper, faster-cutting tooth and aid fast clearing of the gullets. Many hours of testing and drilling literally thousands of holes has helped us refine the tooth grind for the ultimate combination of sharpness, speed, resilience and ease of use in all common materials.