# @stem_antics on Instagram

- **Type:** Video
- **Original URL:** https://www.instagram.com/p/DeNRAsEyO0u
- **Gondola URL:** https://gondola.cc/posts/71427939-stem-antics-instagram
- **Thumbnail:** https://img.gondola.cc/tr:w-,h-,fo-auto/postThumbnails/01b77b38b7.jpg
- **Posted:** 2026-10-07T20:56:12.000+00:00
- **Account Owner:** Stem Antics (@stem_antics) — https://gondola.cc/stem_antics

## Caption

A drill turning at thousands of RPM inside solid steel has one fundamental problem: the hottest, most violent zone in the entire operation sits at the bottom of a blind hole, exactly where flood coolant cannot reach.

Through-coolant drills solve this by turning the tool itself into a pressurised delivery system. Coolant enters through the machine spindle, travels down internal channels inside the drill body, and exits through ports on the flank faces directly behind the cutting lips.

How it works:
- Coolant is fed through a rotary union in the spindle, typically at 20 to 70 bar, with high-pressure systems exceeding 100 bar
- In solid carbide drills, the channels are formed during extrusion of the carbide blank, twisted to follow the helix of the flutes
- Fluid exits at the point, absorbs heat at the chisel edge and cutting lips, then reverses up the flutes
- That reverse flow physically flushes chips out of the hole rather than relying on flute geometry alone

Why it matters:
- Conventional twist drills generally require peck cycles beyond roughly 3 to 4 times diameter
- Through-coolant carbide drills routinely reach 8xD, 12xD and even 30xD in one continuous plunge
- Lower edge temperature reduces built-up edge, crater wear and thermal cracking
- Chip packing, the leading cause of drill breakage, is largely eliminated, allowing higher feed rates

The lineage traces back to deep-hole drilling for firearm barrels, where the single-lip gun drill pumps oil through a hollow shank and ejects chips along a V-shaped external flute. The BTA system, developed in Germany in the 1940s, reversed that architecture, pumping coolant around the outside of the tool and evacuating chips through its hollow centre.

The modern carbide drill compresses that principle into a tool only a few millimetres across.

The cutting edge is only as good as what reaches it.

#stemantics #machining #manufacturing #cnc #engineering

## Stats

- **Views:** 0
- **Likes:** 97
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- **Comments:** 4

## Tags

machining, engineering, cnc, manufacturing, stemantics

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