RobodrillRaj
April 2, 2026 · Original Post
We have two Fanuc Robodrill α-D21MiB5 machines running a high-mix production cell making stainless steel medical components. The tool life management (TLM) system is set up with cycle count limits and we're getting random tool breakage crashes because broken tools are not being flagged. The spindle load monitor threshold is set conservatively and it's still not catching it. We're using D21 control with latest parameter backup from October 2025. This is costing us rejects and we're seriously considering going to a third-party broken tool detection system but wanted to know if anyone has solved this within the Fanuc ecosystem first.

KarenCzech_PragueShop
April 4, 2026
The Robodrill's built-in spindle load monitor is honestly not reliable for small-diameter tool breakage detection — it's designed to catch gross overload, not the subtle signature of a broken 2mm end mill. What solved this for us is using Fanuc's PMC ladder logic to implement a "cutting re-entry load spike check" — you compare spindle load during the first 0.5 seconds of each tool engagement against a baseline. A broken tool shows a characteristic load signature 12–18% below nominal at entry rather than the normal ramp. Fanuc's application engineering team will help you write this PMC customization free of charge if you're a registered machine owner — it's not documented anywhere public but it's standard knowledge in their AE team. Ask for the "broken tool detection ladder template" by name.

NicolasMorton_MedDevice
April 7, 2026
For medical device work specifically — you really should be looking at vision-based tool checking at the ATC if you haven't already. Blum NT laser tool measurement systems integrate directly with Fanuc controls via macro B and can detect a broken tip on tools as small as 0.5mm diameter during the ATC cycle, adding only 2–3 seconds per tool change. Given that you're running stainless medical components, a single crashed part that gets through to inspection costs far more than the system. Blum's TCM (Tool Condition Monitoring) module in their 2025 firmware also logs historical tool wear trends per tool type which is valuable data for your process capability documentation under FDA 21 CFR Part 820 if you need to go that route.

WojPawlak_Automation
April 11, 2026
One more thing nobody mentions — check your Robodrill's skip signal timing for the tool measurement macro (G31). On high-speed cells, if the machine parameter for skip signal filter time (usually parameter 6201) is set too tight for your electrical environment, you can get ghost tool length measurements that put incorrect TLM baselines into the offset table. We had three months of mysterious "random" crashes that turned out to be intermittent G31 skip signal noise from a nearby EDM machine sharing a power circuit. Adding a line filter on the spindle measurement circuit and changing parameter 6201 from 2ms to 4ms eliminated it completely. Cross-contamination between machines on a shared electrical panel is way more common than people admit.