--- title: How to Choose the Perfect 0.2 mm PCB Drill Bit for Reliable Micro‑via Fabrication siteUrl: https://logzly.com/circuitdrillbits author: circuitdrillbits (Precision Drilling Hub) date: 2026-06-20T17:04:05.575629 tags: [microvia, pcbdrilling, makerlife] url: https://logzly.com/circuitdrillbits/how-to-choose-the-perfect-0-2-mm-pcb-drill-bit-for-reliable-microvia-fabrication --- If you’ve ever tried to drill a micro‑via and ended up with a ragged hole or a broken tip, you know the frustration. In today’s world of tiny wearables and high‑frequency boards, a clean 0.2 mm hole isn’t a luxury—it’s a requirement. Getting the right drill bit can mean the difference between a working prototype and a batch of scrap. ## Why 0.2 mm Matters A 0.2 mm via is about the width of a human hair. It’s the sweet spot for high‑density interconnect (HDI) boards where space is at a premium. For a broader view of via size selection, see our [drill bit selection for larger 0.8 mm vias](/circuitdrillbits/choosing-the-right-drill-bit-for-0-8-mm-vias-a-practical-guide-for-hobbyist-pcb-makers). Too big and you waste copper; too small and the plating process can choke. The drill bit you pick must stay sharp, stay true, and survive the heat of a CNC spindle. ## Material Choices: Carbide vs. HSS ### Carbide – The Workhorse Carbide bits are the go‑to for most makers who need consistency. They are harder than steel, so they keep a sharp edge longer. The downside? They are brittle. If you hit a hard spot or apply too much pressure, the tip can chip. **When to pick carbide:** - You run a high‑speed spindle (30 k‑40 k RPM). - You need many holes per session. - You can afford a slightly higher price. ### HSS (High‑Speed Steel) – The Gentle Giant HSS bits are softer, which makes them more forgiving if you accidentally push too hard. They dull faster, especially at the tiny 0.2 mm size, but they are cheap enough to replace often. **When to pick HSS:** - You are just starting out and want to experiment. - Your spindle runs slower (under 20 k RPM). - You prefer a bit that won’t shatter on a mis‑step. ## Coating: TiN, TiAlN, or None? Coatings act like a protective skin. Titanium Nitride (TiN) gives a gold‑ish finish and reduces friction. Titanium Aluminium Nitride (TiAlN) handles higher temperatures better. For a 0.2 mm bit, the coating can be the difference between a smooth cut and a burnt tip. - **TiN** – Good for most hobbyist rigs. It extends life by about 30 %. - **TiAlN** – Worth it if you run at 40 k RPM or higher. - **No coating** – Acceptable if you only need a few holes and want to keep costs down. ## Geometry: Point Angle and Flute Count ### Point Angle The point angle is the sharpness of the tip. A 118° angle is common for general drilling, but for micro‑vias a 135° angle gives a cleaner entry and less wandering. ### Flutes Flutes are the grooves that carry chips away. A single‑flute bit removes material quickly but can cause chatter (vibration). A double‑flute bit is more stable, which is crucial at 0.2 mm. **My go‑to:** A 135° point, double‑flute, TiAlN‑coated carbide bit. It feels like the difference between a scalpel and a butter knife. ## Feed Rate and Spindle Speed Even the best bit will fail if you feed it too fast. For a 0.2 mm hole, keep the feed rate under 0.02 mm per revolution. Pair that with a spindle speed of 30 k–35 k RPM. The rule of thumb is “high speed, low feed.” It reduces heat and keeps the bit from wandering. ## Chuck and Collet Compatibility A tiny bit can wobble if the holder isn’t snug. Use a 1 mm collet or a precision ER‑11 holder. I once tried to use a standard 3‑jaw chuck on a 0.2 mm bit and ended up with a crooked via that looked like a tiny canyon. Lesson learned: the right grip matters as much as the right material. For a complete walk‑through of holder selection and spindle alignment, see our [step‑by‑step DIY precision drilling setup](/circuitdrillbits/stepbystep-diy-precision-drilling-setup-from-tool-selection-to-perfectly-aligned-holes). ## Testing Before the Real Deal Before you drill the actual board, run a test on a scrap piece of FR‑4. Check three things: 1. **Hole shape** – Should be round, not oval. 2. **Debris** – Little chips, not a smear of plastic. 3. **Tip wear** – If the tip looks dull after a few holes, it’s time to replace. A quick test saves you from ruining a costly prototype. ## Cost vs. Longevity You’ll find 0.2 mm bits priced anywhere from $2 to $15. The cheap ones are usually HSS, no coating, and may have a 118° point. The pricey ones are carbide, TiAlN‑coated, 135° point, and double‑flute. If you plan to make more than ten boards a month, the higher‑end bit pays for itself in reduced breakage and better yields. ## My Personal Story When I first tried micro‑via drilling for a wearable sensor, I bought a $3 HSS bit, set my spindle to 15 k RPM, and fed at 0.05 mm per rev. The result? A broken tip and a board that looked like a Swiss cheese. I switched to a $12 carbide bit with TiAlN coating, cranked the spindle to 32 k RPM, and slowed the feed to 0.015 mm per rev. The first hole was so clean I could see the copper plating line with the naked eye. That moment made me realize that the right bit isn’t an expense—it’s an investment in reliability. ## Quick Checklist Before You Buy - **Material:** Carbide for longevity, HSS for cheap trials. - **Coating:** TiAlN if you run high speeds, TiN for moderate use. - **Point angle:** 135° for clean entry. - **Flutes:** Double‑flute for stability. - **Holder:** 1 mm collet or ER‑11 for zero wobble. - **Speed/Feed:** 30–35 k RPM, feed <0.02 mm/rev. Keep this list on your desk, and you’ll never pick the wrong bit again. ---