Post-Editing Comparison: gemini-4-argon

This is the text corrected by gemini-4-argon. The input document is Post-Editing Comparison: Input Document. In both runs, we had it edit the text in polite form (--tone desu). The corrected text has not been placed into the original page. [Trial]

• Run 1 (original prompt): Took 67 seconds. There was 1 place where the meaning shifted. "Therefore" was inserted between two sentences that were originally placed side by side, making it read as if board frame grounding and shielding near the welder were a consequence of the differential design.
• Run 2 (prompt with 2 added rules): Took 49 seconds. No places were found where the meaning shifted. "Therefore" was not inserted, and the sentences connected with "When used near a welder."
• The added rules are: "Do not soften decisions into suggestions" and "Do not add connections of reason or result that are not in the original."

Run 1 (Original Prompt)

For control, we decided to use LinuxCNC and a Mesa Ethernet card. The deciding factor is that rigid tapping (G33.1) is available. We are considering the 7I76EU as our candidate card (investigated 2026-11). The values here are taken from manuals and sales pages, and we will verify combinations on the actual machine.

Comparison of Control Software

Card Selection

• Spindle-related performance is the same between 7I76EU and 7I96S. The difference is only the number of I/O points.
• Since this machine requires 11 or more inputs, the 7I96S would be completely full on day one. The 7I84U (US$79) for expansion is out of stock, and adding it makes the cost higher than the 7I76EU.
• We also looked into newer cards, but found nothing that would change this decision. The "T" in the name is a revised version of an existing card, not a higher generation.
• If you want to use 2 A outputs directly, the 7I96S is well suited. However, the 500 mA output of the 7I76EU is expected to be sufficient for the solenoid valves and brake (0.18 A).

7I76EU Notes

• Requires LinuxCNC 2.9.3 or higher. A newer version of mesaflash is also used. Because there are reports that some versions of PnCConf do not support it, we assume we will edit configuration files by hand.
• To maintain isolation, keep the 24 V and logic power supplies separate. This is because making them common eliminates isolation.
• Only general-purpose I/O and the analog spindle are isolated. Step, direction, encoder, and RS-422 are designed to withstand noise differentially. Therefore, near a welder, board frame grounding and shielding are important.
• Inputs are sinking type only. To use NPN sensors, pull-ups (2.2 kΩ) are required.
• Board dimensions are unverified. We will confirm them before finalizing the enclosure layout.

Spindle Command

• The primary plan is to drive the A6 servo via step/direction. This eliminates the need for a ±10 V dual power supply and avoids the problem of analog output freezing at startup.
• We use LinuxCNC's stepgen in velocity mode. During orientation, we switch to PID output using a mux.
• Actual rotation is read by dividing the servo's A/B outputs and inputting them into the card's encoder input. Setting it to 1250 lines yields 500 kHz at 6000 rpm. Near a welder, we do not push for too many lines, leaving the input filter intact.
• For the index, we add a 1-pulse-per-revolution sensor to the spindle. This is because with a 2:1 reduction ratio, the servo's Z pulse occurs twice per spindle revolution. Combining A/B from the servo and Z from a spindle sensor is recommended by Mesa engineers on the LinuxCNC forum. There are also examples where this has been run (7I76 + 7I83, 1:1.8 reduction, M3–M6). Feed the signal at 5 V logic.
• There are reports that stopping pulses abruptly caused machine vibration and overvoltage errors. Therefore, we set the stepgen acceleration and test this first along with the A6 regenerative resistor.
• Set the servo torque limit to approximately 6 N·m. This is to ensure momentary belt tension does not exceed the shaft's allowable load (Purchased Parts Specifications and Dimensions).
• Unverified: We found no direct reports of successful servo spindle rigid tapping using the 7I76EU, 7I96S, and A6-RS combination. However, there are reports with the older 7I76 family, and since the spindle functions share the same specifications, it is expected to work. Asking on the LinuxCNC forum before ordering gives peace of mind.
• Instructions for G33.1, signal wiring, holders, and commissioning procedures are compiled in How to Use Rigid Tapping.

I/O

Outputs use 5 points: servo enable, tool release solenoid valve, air blow, orientation command, and coolant. Driver alarms, rack sensors, and operator buttons can be added using the remaining points.

Power Supply and Safety

• The power supply is single-phase 200 V. The A6-1000RS has an input of 9.6 A, with a 20 A fuse, 16 A breaker, and 12 A contactor specified (manual).
• The manual specifies a Type B earth leakage breaker with a sensitivity of 100 mA or higher. We will check this with a licensed electrician. Also, we will place a dedicated branch breaker just ahead of the machine.
• Make sure to ground the system properly. This is the foundation of countermeasures against servo leakage currents and noise.
• Because it will be used near a welding machine, we will add a noise filter, separate the signal lines, and use shielding. Furthermore, do not weld on workpieces while they remain attached to the machine. There is a risk that the welding current could pass through bearings or encoders.
• For emergency stops, we will rely on physical interruption via a contactor as the standard approach. The circuit is not yet designed.

Future ideas

There is also an idea to turn the parts humans write into custom commands and convert them from there into G-code. This is well suited for repetitive tasks like hole patterns, pilot holes, and tapping. We plan to decide whether to adopt this after the machine is completed.

Second run (instructions with two rules added)

For control, we use LinuxCNC and a Mesa Ethernet card. The deciding factor was the availability of rigid tapping (G33.1). The candidate card is the 7I76EU (surveyed in 2026-11). The values here were read from manuals and sales pages, and the combination will be verified on the actual machine.

Comparison of control software

Card selection

• Spindle-related performance is the same between the 7I76EU and 7I96S. The only difference is the number of I/O points.
• Since this machine requires 11 or more inputs, the 7I96S would be maxed out on day one. The expansion 7I84U (US$79) is out of stock, and adding it would cost more than the 7I76EU.
• We also looked for newer cards, but found nothing that would change our decision. The "T" in the name indicates an updated revision of existing cards, not a higher-generation architecture.
• If you want to drive 2 A outputs directly, the 7I96S is well suited. However, even with the 7I76EU's 500 mA outputs, it is expected to be sufficient for the solenoid valves and the brake (0.18 A).

7I76EU cautions

• LinuxCNC 2.9.3 or higher is required. Use a newer version of mesaflash as well. Since there are reports of PnCConf versions that do not support it, we assume the configuration files will need to be edited by hand.
• To maintain isolation, keep the 24 V and logic power supplies separate (sharing them removes the isolation).
• The parts that are isolated are general-purpose I/O and the analog spindle. Step, direction, encoder, and RS-422 are designed to withstand noise via differential signaling. When used near a welding machine, proper board frame grounding and shielding are critical.
• Inputs are sinking only. NPN sensors require pull-up resistors (2.2 kΩ).
• Board dimensions are unverified. We will confirm them before finalizing the enclosure layout.

Spindle command

• The first plan is to drive the A6 servo using step/direction. This eliminates the need for dual ±10 V supplies and avoids the issue where analog outputs peg at startup.
• We use LinuxCNC's stepgen in velocity mode. Spindle orientation is switched to the PID output using a mux.
• Actual rotation is read via the card's encoder input by dividing the servo's A/B outputs. Setting it to 1250 lines gives 500 kHz at 6000 rpm. Near a welding machine, it is better not to get greedy with line count, keeping input filtering intact.
• For the index, we will add a 1-pulse-per-revolution sensor to the spindle. With a 2:1 ratio, the servo's Z signal occurs twice per spindle revolution. Combining A/B from the servo with Z from a spindle sensor is recommended by Mesa engineers on the LinuxCNC forum, and real-world examples exist (7I76 + 7I83, 1:1.8 reduction, M3 to M6). Feed the signal into a 5 V circuit.
• There are reports that stopping pulses abruptly caused the machine to shake and resulted in overvoltage errors. Set up stepgen's acceleration and test this first along with the A6's regenerative resistor.
• Set the servo torque limit to approximately 6 N·m. This prevents instantaneous belt forces from exceeding the allowable shaft load (Purchased parts specifications and dimensions).
• Unverified: We found no direct reports of successfully rigid tapping with a servo spindle using the combination of 7I76EU, 7I96S, and A6-RS. However, there are reports with older 7I76-series cards, and since the spindle functions share the same specifications, it is expected to work. Asking on the LinuxCNC forum before ordering is a good idea.
• How to use G33.1, wiring signals, toolholders, and startup procedures are summarized in How to use rigid tapping.

I/O

Outputs are 5 points: servo enable, tool-release solenoid valve, air blow, orientation command, and coolant. Drive alarms, rack sensors, and operator buttons can be added to the remaining points.

Power supply and safety

• The power supply is single-phase 200 V. According to the manual, the A6-1000RS requires a 9.6 A input, a 20 A fuse, a 16 A breaker, and a 12 A contactor.
• For the earth leakage circuit breaker, the manual specifies Type B with a sensitivity of 100 mA or higher. We will check this with a licensed electrician. We will place a dedicated branch breaker right before the machine.
• Grounding must be done reliably. This forms the basis for dealing with servo leakage current and noise.
• Because it will be used near a welding machine, we will add a noise filter, separate the signal lines, and use shielding. Do not weld on a workpiece connected to the machine. There is a risk that welding current could pass through the bearings or encoder.
• The emergency stop will primarily rely on physical cutoff via a contactor. The circuit is still undesigned.

Future ideas

There is an idea to write the human-authored parts using custom commands and convert them into G-code. This is well-suited for repetitive tasks like hole patterns, pilot holes, and tapping. We will decide whether to adopt this after the machine is finished.