## Bambu Lab A1 I purchased GNK to increase my capacity to print functional parts. On February 17, 2025, I added the AMS Lite. While it has the capability for multi-material printing, I use it primarily for continuous printing. Being able to load multiple spools of the same material means GNK can run for longer stretches without requiring me to swap filament. This feature aligns well with how I use it—as a steady background worker in the shop.   ## Current Mods The only notable modification is the installation of the AMS Lite in February. For most of its life, GNK ran a 0.6 mm nozzle, which was well-suited to the functional parts I needed. I've upgraded the original stainless steel nozzle to a hardened steel variant. On May 31, 2025, I switched to a 0.4 mm nozzle, and that remains its current configuration.   In late July, after quality issues appeared, I replaced the extruder gears on July 29, 2025. That change didn't fix the underlying problem. Eventually, after a second catastrophic failure in August, I performed a full hotend service—installing a new heater block and nozzle on August 25, 2025. The repair fixed the quality issues it was experiencing. The heater block had become fouled and the hotend was never coming up the the appropriate temperature. ## History - 2025-01-28: I purchased without AMS Lite and switched from the factory nozzle to a 0.6mm. - 2025-02-17: I installed AMS Lite - 2025-04: Frequent extruder jams. I traced the problem to the inexpensive Jayo PETG filament I was using. I found foreign particles in the extruder on many occasions. - 2025-05-31: I switched back to the original stainless 0.4mm nozzle - 2025-06-16: The original stainless steel nozzle finally wore out after 2016 hours of use. - 2025-07: Blob of Death. I cleaned it as thoroughly as possible, but the quality was not as good as before.   - 2025-07-29: I replaced extruder gears, hoping to address the quality issue. No improvement. - 2025-08-21: Second Blob of Death. This time I couldn't clean it thoroughly. The machine was out of order until I could obtain a new heater block. - 2025-08-25: I replaced the heater block and nozzle. The print quality returned to factory levels. Apparently, my repair of the first Blob of Death was incomplete. Sometimes cleaning is not enough—the only way forward is complete replacement. - 2026-01-25: The printer can no longer detect the existence of the build plate or do a z-axis level. I'm going to need to tear the toolhead down to figure out what the problem is. - 2026-02-24: Repaired build plate detection. [[#2026-02-24 "Repair"|See below]] for details. - 2026-03-18: Started to skip z-axis moves. Also failed to Z-calibrate once. I'm still working through debugging this one. Current potential problems: - Z-belt slip - Electrical problem with Z motor - Hitting a new firmware bug. There were some z-axis motion bugs fixed in 1.07 ## Planned Upgrades I do not plan any more upgrades to GNK. I always intended for GNK to be a capacity-expander, not a long-term cornerstone. Once I have most of my Voron printers built and running, I will sell GNK.   ## Current State After the August repairs, GNK is back to producing clean, reliable prints. It is currently set up with a 0.4 mm nozzle and runs primarily PETG and PLA for functional parts. While it remains a dependable machine, it will not be part of the long-term fleet. ## 2026-02-24 "Repair" I was worried about this repair. GNK suddenly stopped detecting the build plate. Any attempt to start a print failed to detect the build plate. Given that the A1 relies on a toolhead load cell for bed probing, I was concerned I’d be looking at a toolhead teardown, replacement parts, and a decision about whether this printer was still worth the effort. I put GNK on the bench and watched the probing sequence in slow, methodical steps. During plate detection, the nozzle should move to the rear portion of the build plate, press down, and let the load cell register contact. Instead, the nozzle was failing to reach the target area and was dropping into the plate's slot. It never made mechanical contact with the plate, so from the firmware’s point of view, the plate simply “didn’t exist.” That pointed to a positioning problem, not a failed sensor. I walked through the homing routine and quickly noticed something off on the Y-axis: the heat bed wasn’t reaching its true home position. A small chunk of filament waste had wedged itself on the rear Y-axis rail, stopping the carriage a few millimeters early. The printer thought it was at Y=0, but it was physically shifted forward—just enough that the probing position lined up with the gap behind the plate rather than the plate itself. Once I removed the filament scrap and re-homed the machine, plate detection worked perfectly. No toolhead teardown, no new parts—just a tiny obstruction causing a big failure. This was a good reminder that before you start swapping electronics or sensors, it’s worth verifying the fundamentals: homing behavior, hard stops, and anything that could physically keep the axes from reaching their reference positions. ## Current hours As of 2026-03-28, this printer has 5877 print hours. > [!note]- Colophon   > ![[Printer Naming#GNK]] ![[Discussions]]