Standalone batch workflow for engraving 100 coasters from the TTS-20 Pro touchscreen

Running a 100-piece coaster job without a PC requires building the right offline assets, a repeatable physical jig, and an operational rhythm that keeps the laser, operator, and work area safe during continuous cycles. This article shows how to prepare .nc/.gcode assets the TTS-20 Pro can read, organize files and names for fast touchscreen selection, set up a registration jig for consistent placement, and manage cooling, supervision, and cycle verification during long runs.

What you need on the bench and in files

  • A TwoTrees TTS-20 Pro with its integrated standalone controller and touchscreen (verified fit for offline control).

  • Properly formatted physical storage (TF/microSD) or supported local transfer method that the machine reads. Confirm card format and filename rules in the machine’s download/firmware notes (TwoTrees Download Center).

  • Master vector or raster artwork exported to the machine’s accepted instruction format—structured .nc or .gcode files matching the machine’s coordinate convention (origin, units, and motion commands). The TTS-20 Pro requires these precompiled instruction files for offline running.

  • A repeatable registration jig sized to your coaster material and clamping method (double-sided tape, vacuum, or mechanical hold-downs appropriate for the TTS-20 Pro work area).

  • Fire-safe workspace, smoke extraction, and a designated operator who will supervise the entire run.

File prep: compile once, run 100 times

  1. Choose and frame your artwork to the coaster working envelope. Decide whether each file will contain one coaster design or a multi-coaster array matching your jig. Single-coaster files reduce risk when a single piece fails; array files speed overall cycle time but increase rework when misaligned.

  2. Set a fixed coordinate origin in your CAM export that matches the registration jig’s reference point (for example: front-left corner of the jig = machine origin). Record whether exported coordinates are in millimeters or inches and keep that consistent for every file.

  3. Export to the required offline instruction format (.nc or .gcode) and verify the file contains explicit motion commands and laser on/off markers the TTS-20 Pro reads. The PRODUCT FIT LIMITATION requires this precompiled syntax; the machine’s offline controller does not convert raw SVG or proprietary project files.

  4. Name files for rapid touchscreen selection. Use a clear sequence and short names so the filename is readable on the 3.5-inch control display, for example: COA_001.nc, COA_002.nc … COA_100.nc or COASTER_A1.nc (if using array files). Avoid long verbose names that truncate on small displays.

  5. Place a small verification header or comment (if supported) inside each file containing units and origin, e.g., ;UNITS=MM ;ORIGIN=FRONT_LEFT — this helps re-check compatibility if you must re-generate files later.

Storage card formatting and file transfer

  • Use a TF/microSD card that matches the machine’s supported capacity and format (check the machine’s download and support pages for specific limits). A typical safe approach is FAT32 formatting for cards up to common consumer sizes, but confirm details on TwoTrees Download Center.

  • Copy the .nc/.gcode files into the card root or the folder structure the controller expects. Keep the card tidy: remove unrelated files and create a simple numeric ordering so touchscreen scrolling is minimal.

  • Eject the card safely from your computer and insert it into the TTS-20 Pro. On first runs, load a single test file to confirm the card and filenames display as expected.

Physical registration jig: repeatability is everything

  • Build a jig that locks each coaster into the same XY position and orientation. Options: a laser-cut frame with pockets sized to the coaster (0.1–0.5 mm clearance), a simple MDF template with pilot pins, or a modular bed with removable stops.

  • Use consistent workpiece thickness or include a shim to keep the top surface at a known Z height. If coaster thickness varies, use a flat reference shim under every piece or set Z zero using the same mechanical probe method each cycle.

  • Label the jig origin (front-left or another reference) to match your file origin. The machine’s offline coordinates must be referenced to this physical mark.

  • Secure material against movement using low-profile clamps, double-sided high-temperature tape suitable for laser heat, or gravity plus edge stops. Avoid adhesives that release harmful fumes under laser exposure.

Touchscreen operation: selection, framing, and start

  1. Insert the TF card and open the file browser on the TTS-20 Pro touchscreen. The integrated 3.5-inch interface controls motion, framing, and file selection (verified).

  2. Select the first file (e.g., COA_001.nc). Before running, use the machine’s dry-move or rapid jog to bring the laser head to the expected origin and visually confirm alignment with your jig origin.

  3. Use the built-in framing or boundary preview feature to verify the engraving area fits inside the coaster pocket. Framing while the laser is off is safer and faster for confirmation.

  4. Confirm focal height and that any air-assist, extraction, or dust-collection systems are on. Set the appropriate laser focus for marking (not cutting) to protect the workpiece and lens.

  5. Start the job from the touchscreen and supervise continuously. Do not leave the machine unattended during operation—even when using offline cards.

Cycle management for 100 pieces

  • Decide on run strategy: continuous single-file repeats versus one-file-per-piece. Recommended for reliability: run single-piece files or small arrays and repeat the sequence; this limits impact of a single misfeed.

  • After each cycle, stop and inspect the output (first 10–20 pieces should be spot-checked more frequently). Check for consistent registration, focal condition, and smoke residue.

  • Replace consumables proactively (lens, air filter, tape) if marking quality drifts. Small variations in focus or soot on optics will change engraving contrast quickly across many pieces.

  • Monitor machine temperature and allow short cooldown pauses if the machine or laser driver indicates thermal stress. Continuous high-duty engraving increases internal temperatures; operator supervision must manage pacing.

Heat, extraction, and safety during long runs

  • Keep a functioning smoke extractor or ventilation directly over the work area. Engraving 100 coasters will generate continuous smoke and particulates.

  • Have a fire extinguisher rated for electrical and solid-fuel fires within easy reach. Never rely on an enclosure alone as fire protection.

  • Wear eye protection appropriate to the laser wavelength when the enclosure is open. Confirm that any accessory eyewear meets the manufacturer’s suggestions—do not assume universal ratings.

  • Never run the laser unattended. The machine’s standalone controller does not remove the need for continuous supervision.

Troubleshooting common offline-run problems

  • Files do not appear on the touchscreen: reformat the TF card to the machine’s supported filesystem and copy a single small .nc file to test. Confirm the card reader is clean and the file naming uses supported characters (avoid special symbols).

  • Engraving shifted off-jig: verify coordinate origin in the file header and the physical jig origin alignment, then run a dry-frame move to check X/Y offsets. Re-generate files if the origin convention differed.

  • Quality falling mid-run: stop the run and check lens and mirrors for soot; verify air-assist and extraction are operating; check laser module temperature. Replace or clean optics as recommended by TwoTrees’ maintenance notes.

  • Unexpected termination or paused jobs: check for control panel error messages, card read errors, or thermal protection triggers. If a file is partially processed, re-evaluate whether to re-run that piece or discard it.

Workflow example (practical sequence)

  1. Day-before: generate .nc files, name COA_001…COA_100, copy to TF card, build and test-fit jig.

  2. Morning: install extractor, insert card, run 3–5 test pieces to confirm registration and quality.

  3. Production: run batches of 10–20, performing a quick inspection at the end of each batch, clearing soot, and ensuring consistent clamping.

  4. End-of-day: clean optics, inspect clamps and jig, and back up the TF card contents to a computer.

When a PC becomes necessary

Offline workflows are efficient for repeatable runs but require that the .nc/.gcode be correct beforehand. Use a PC if you need to:

  • Modify files on the fly or correct an origin offset between jobs.

  • Re-slice or recompile artwork into a different toolpath or coordinate system.

  • Automate generation of 100 unique numbered files from a template.

Where to get firmware, file templates, and support

  • TwoTrees provides downloads for firmware, example files, and documentation that clarify accepted card formatting and controller behavior: TwoTrees Download Center.

  • If you need bundled hardware for production workflows (workholding, jigs, extraction), see TwoTrees’ accessory and kit offerings: Laser Engraver Bundles.

Practical limitations and final cautions

  • The TTS-20 Pro’s standalone controller can run precompiled .nc/.gcode files, but it will not accept raw SVG or uncompiled project files; you must compile instructions beforehand.

  • Do not rely on enclosure, camera, or remote notification systems to replace active supervision. Continuous operation raises both fire and equipment-heat risk.

  • Automated physical reloading or part ejection is not supported—every piece requires manual placement or a non-automated jig.


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