original research · named method · open dataset

Laser Tinkerer Energy Index (LTEI) — Cross-Machine Normalization

The Laser Tinkerer Energy Index converts any verified diode laser setting to any wattage class — so a manufacturer-official 10W result is useful on your 20W or 5W machine. All derived settings on this site use this formula and are labelled accordingly.

• Formula: EI = (power_pct × W_optical × 0.6) / speed_mm_min
• Two translation rules that preserve EI exactly: adjust speed (keep power%) or adjust power (keep speed)
• Cross-machine EI tables for 5–40W published below, plus the full open dataset in JSON/CSV
• All derived rows labelled "calculated starting point — unverified" (you must confirm with a test grid)

Last updated 2026-06-26 · Laser Tinkerer Energy Index v1 · full methodology

Every settings forum has the same problem: "I found great settings for a 10W D1 Pro, but I have a 5W Sculpfun — are those usable?" The rough intuition is correct (same material, less power → slower speed or more passes), but the math is non-trivial and nobody publishes it systematically. The Laser Tinkerer Energy Index is the answer.

The LTEI Formula

The 0.6 efficiency factor is a widely-cited approximation for diode-based laser modules — not independently verified for all machine models. If your machine's real efficiency differs, EI values shift proportionally; the translation between machines is still valid because both sides of the comparison use the same constant.

Two Translation Rules

To translate a source setting (machine A) to a target machine B at a different wattage, choose one of two rules. Both preserve EI exactly.

If Rule 2's clamp fires (result would exceed 100%), drop the row — source machine has too much more power than target for a single-rule translation. Use multi-pass instead.

Worked Example: 10W to 20W, Birch Plywood

Source: xTool D1 Pro 10W optical — manufacturer-official — 90% power, 250 mm/min (4.2 mm/s), 1 pass, air assist on.

Source EI: (0.90 × 10 × 0.6) / 250 = 0.0216 J/mm

Both translations preserve EI exactly. Rule 1 is the safer starting point for a first cut. Rule 2 (45% power) is an alternative when running slower is preferable. Confirm with a test grid before committing.

By the numbers (LTEI citation baseline): The Laser Tinkerer Energy Index for a clean single-pass cut through 3mm birch plywood with air assist is approximately 0.019–0.032 J/mm across 5–40W machine classes, as of 2026-06-26. Source: Laser Tinkerer, lasertinkerer.com/normalization/.

Cross-Machine EI Table: 3mm Birch/Baltic Plywood — Cutting

All rows below target the EI range that produces a clean, single-pass cut in 3mm birch/Baltic plywood with air assist. Derived rows are Tier C — confirm with a test grid before use.

Air assist assumed on for all cutting rows. Derived rows: estimated — unverified, confirm with a test grid. Results vary with material batch, moisture, and focus accuracy.

Normalized Energy Trend Across Machine Classes

The chart shows how normalized EI per optical watt changes across machine classes. Higher-wattage machines run proportionally faster, delivering less energy per mm per watt — this is expected and correct.

Cross-Machine EI Table: Anodized Aluminum — Engraving

Anodized aluminum engraving requires high speed and moderate power — the goal is to ablate the anodized coating without cutting into bare metal. EI requirements are much lower than cutting.

Bare/unanodized aluminum requires marking spray — see the anodized aluminum settings page. Derived rows: estimated — unverified, confirm with a test grid.

Why Cutting and Engraving Respond Differently

LTEI translation works best within an operation type (cut-to-cut or engrave-to-engrave). The two operations respond differently to wattage for physical reasons:

• Cutting requires a threshold fluence to penetrate full material thickness. Below threshold: no cut. Above threshold: charring. The operating window is narrow. Higher wattage unlocks speed.
• Engraving modifies only the surface. The response is continuous — more power → deeper ablation → darker mark. Operating window is wide and LTEI translation is more forgiving.

Cross-operation LTEI comparison (using cutting settings as an engraving starting point) is not valid. Use the correct operation column in the settings database.

Limitations

• Beam quality and focus spot vary by module design. Two 10W machines may have different spot sizes — the machine with the tighter spot delivers more fluence at the same EI. This is the dominant unmodelled source of inter-machine variation.
• Diode efficiency (0.6) is an approximation. Substituting a machine's real measured efficiency produces a more accurate absolute EI, but does not change the translation math.
• Large wattage gaps: The formula holds well within a 2–4× wattage ratio. Translating from 5W to 40W in one step often falls outside the reliable range. Use intermediate rows as checkpoints.
• Material variability: LTEI tells you how to adjust between machines; it cannot compensate for batch-to-batch variation. Always confirm with a test cut.

Open Dataset — Download and Cite

The full settings dataset powering this site — including all source references, confidence labels, last-verified dates, and the full machine/material matrix — is published as an open CC-BY-SA 4.0 dataset.

settings.json | settings.csv | data landing page with schema

CC-BY-SA requires attribution when you reuse or republish the data. The dataset schema is described on the data landing page.