50W Fiber Laser Brass Engraving Settings and Depth Guide

Why Brass Demands Serious Power

Brass fights back when a laser touches it. The alloy pulls heat out of the impact zone faster than low power heads can replace it, which is why cheap diode boxes leave bare brass looking untouched while they happily engrave painted or coated stock. A 1064nm fiber source changes the physics: the beam couples straight into the metal, and a 50W supply gives each pulse enough energy density to vaporize material before the heat runs away into the blank.

This brass engraving settings guide is built around one desktop machine, the GWEIKE G2 Max 50W, and around one material family, copper zinc alloys in coin, jewelry, tag, and card form. It covers the processes that turn a beam into a mark, the settings that produce real depth, and the fixes for the five problems that actually show up at the bench. If you already own the machine, the parameter table in the middle of this article is the part to print. If you are deciding whether 50W is worth the step up, the documented coin build will answer it faster than any spec sheet.

The three processes behind every mark

Material Ablation

Ablation means direct removal. A high intensity pulse hits the surface and a thin layer vaporizes, ejects as smoke, and the floor drops a fraction of a micron. Repeat the pass and the depth accumulates. Roughly 0.01mm comes off per pass on brass at 50W, so one hundred passes buys about 1.0 mm of depth. Brasses reward this process with clean edges and a floor that stays sharp once the smoke clears.

Laser Annealing

Annealing runs hot but gentle. Power drops to 20 to 40 percent and speed slows down until the surface stays below vaporization. Under that heat the metal grows a thin oxide layer beneath the skin, and the oxide turns black without breaking the material open. Serial numbers, barcodes, and tool tags all rely on this mode. The engraving survives handling because it sits below the surface rather than on it, which also means it outlasts a painted mark by years of shop abuse.

Color Oxidation

Push the heat into a narrow window on stainless or titanium and the oxide film grows to a controlled thickness. Thin film interference turns that thickness into color, and by stepping power and frequency the same head walks through more than ninety distinct shades. On brass the palette narrows to golden browns and dark anneals, so most brass work stays in ablation and annealing modes and saves the color palette for other blanks.

Machine Anatomy and What It Changes

The G2 Max 50W is a Class 4 fiber engraver built around a 50W, 1064nm, non-MOPA source. The galvanometer scans at up to 15000 mm/s with a rated accuracy of 0.001 mm, and the 150 x 150 mm working area holds two coin blanks in parallel. An electric lift column sets focus by button press, dual red light pointers preview the cut path, and GLaser or LightBurn runs the job over WiFi or USB. The frame spans 17.2 x 10.1 x 21.2 inches and the 50W model lists at $2,599.

Two smaller siblings share the platform. The G2 Pro 30W with a 110 x 110 mm area lists at $1,799, and the G2 Pro 30W with a 150 x 150 mm area lists at $2,099. All three scan at 15000 mm/s, so the upgrade buys ablation energy per pulse and nothing else. An extra 20W roughly halves the pass count needed for a given depth on brass, and that difference is the entire argument for the 50W model.

Choosing Brass for the Job

Reading the Alloy Code

• C26000 cartridge brass, 70/30 copper to zinc, is the default. It engraves clean and sharp with minimal discoloration, and every number in the parameter table below assumes this alloy.
• C28000 red brass, 85/15 copper to zinc, conducts heat faster, so add 10 to 15 percent power at equal speed.
• C36000 free cutting brass trades a small amount of sheet smoothness for machinability thanks to its lead content, and it needs harder extraction than the rest.
• C23000 yellow brass behaves like C28000 and shows up most often in sheet form at hardware and metal suppliers.

Thickness by Project

• Coins and medallions do their best work in 1mm sheet, thick enough to hold a full millimeter of depth without curling, and reaching that depth takes roughly 1 to 3 hours of passes.
• Jewelry blanks for rings and pendants usually sit between 0.5 and 0.8mm, and thinner stock needs lower power to avoid curl along the edges.
• Dog tags and nameplates live at 0.3 to 0.5mm in stainless or brass for shallow identification work.
• Metal business cards can be profiled from 0.1 to 0.3mm sheet by extreme ablation at very slow speed.

Surface prep decides whether those clean edges actually show up. Wipe the blank with 90 percent or stronger isopropyl alcohol to strip skin oils, sand at 400 grit if oxidation has formed, wipe again, and keep fingers off the working face afterward. Contamination does not just look bad; it absorbs energy unevenly and produces patchy, inconsistent results.

The Parameter Table for Brass and Related Metals

Speed in these rows is mm per minute unless noted, and frequency is in kHz. The depth column assumes 0.01mm removed per pass on brass.

Material	Power	Frequency	Speed	Passes	Depth	Process
Brass, deep engraving	20 to 90 percent	80	15000	100	about 1.0 mm	Ablation
Brass, cleanup pass	20 percent	78	3000	1	floor smoothing	Melt and smooth
Brass, surface marking	30 to 50 percent	20 to 40	500 to 2000	1 to 3	under 0.1 mm	Ablation
Copper, deep engraving	40 to 80 percent	20 to 40	500 to 2000	50 to 150	0.5 to 0.8 mm	Ablation
Stainless, annealing	20 to 40 percent	80 to 100	slow	1	black surface	Annealing
Stainless, color	20 to 40 percent	80 to 100	variable	1	thin oxide	Color engraving
Titanium, color	20 to 40 percent	80 to 100	variable	1	thin oxide	Color engraving
Thin sheet, through cut	80 to 100 percent	20 to 50	very slow	50 to 200	through 0.1 to 0.3 mm	Extreme ablation

A Documented Coin Build

One user report captured the reference result. A 1mm thick, 20mm diameter brass blank ran at 15000 mm per minute, 20 to 90 percent power, 80 kHz, and 1000 dpi for one hundred passes, and the depth landed at 1.0 mm with detail intact on the first attempt. The cleanup pass ran 3000 mm per minute at 20 percent power and 78 kHz, applied as one cleanup for every four cutting passes. The same report notes the floor took practice before the smoothness matched the quality of the detail, which is normal for a first run of a new recipe.

Fiber Versus Diode on Bare Metal

Diode engravers at 450nm sit on the wrong side of the absorption curve for bare metal. Paint soaks up blue light and burns away cleanly, which is why diode owners engrave coated stock happily and report almost no effect on bare brass. A 1064nm fiber beam reflects differently: metals absorb it strongly enough to vaporize, so the same head that anneals a tag also ablates a coin. Speed tells the same story. Diode work in practice tops out around a few hundred to a thousand mm per minute, while the galvanometer in the 50W model runs 15000 mm/s, so fiber jobs finish in minutes what a diode would need hours to attempt, and the diode still would not reach depth on bare brass. Maintenance also favors the fiber head, since the solid state source asks for almost nothing while diode bars dim with age.

Other Materials That Work in This Machine

• Copper behaves like thirsty brass and reaches 0.5 to 0.8 mm in 50 to 150 passes at 40 to 80 percent power.
• Stainless steel anneals black for durable identification and colors through oxide thickness when you want decoration.
• Titanium is the color king of the palette, walking through ninety plus shades by power and frequency steps.
• Leather darkens without cutting through, which makes it a quick test material for a new design.
• Dark glass frosts on tinted bottles and tumblers for a store-bought look.
• Colored ceramics give up their glaze to reveal the layer underneath.
• Stone such as granite, marble, and basalt handles memorial and decorative pieces.

How Grayscale Power Makes 3D Relief

Relief works as depth with a map. A grayscale image drives it: white stays at the surface, black sinks to full depth, and every gray in between maps to a power level at fixed scan geometry. Load the image into LightBurn or GLaser with 3D mode on, set the depth ceiling, and the galvanometer walks the power curve line by line at 15000 mm/s. The 0.001 mm rated accuracy keeps the steps tight enough that the relief reads as a smooth sculpture instead of a staircase. Coins and medallions make the natural first project, since the 150 x 150 mm bed holds a full relief portrait with room to spare.

Cutting Thin Sheet Stock

A 50W fiber head profiles thin stock rather than cutting thick plate. Stainless, brass, and aluminum sheet between 0.1 and 0.3mm goes through with extreme ablation at very slow speed, the same recipe as the deep coin pass but aimed straight down through the material. Fifty to two hundred passes are normal for a clean edge on 0.2mm stock. Anything 1mm or thicker needs an industrial 1000W class cutter, so treat sheet work as a bonus capability rather than the main event. Thin stainless warps when power outruns speed, so back the sheet and step the power down before blaming the machine.

Fixing the Problems That Actually Happen

Depth Shortfall

Shallow results after the planned pass count almost always trace to one of four causes: power set too low for the alloy, frequency set too high, a contaminated lens, or a dirty blank. Step the power up in 10 percent increments from a 70 percent base, drop frequency into the 20 to 40 kHz band, clean the optic, and degrease the surface. Budget 80 to 150 passes for 1mm of depth on 1mm brass at 50W, and run a test square on scrap before committing the real blank.

Rough Floors

Pitted floors usually mean the cleanup pass is missing, too hot, or running at the wrong frequency. Add it at 20 percent power, 3000 mm per minute, and 78 kHz, with one cleanup for every four cutting passes. If the floor still looks rough, drop the cleanup power to 15 percent and slow down further; the melt pass needs a gentle touch to smooth the floor rather than dig into it.

Discoloration Around the Mark

A purple or golden halo signals oxidation rather than ablation. Heat input crossed the line, so trim power by 10 to 15 percent, raise scan speed, or nudge frequency upward. Eighty kHz sits at the middle of the road on brass. Let long jobs cool between passes, and if the halo persists, a light coat of anti spatter spray on the blank keeps the run cleaner and the optic happier.

Lens Contamination

Depth fades slowly across a long session when zinc vapor condenses on the focusing lens. Wipe the optic with lens tissue and 99 percent isopropyl alcohol after every deep job, and run the extractor for the whole session. Brass ablation is abrasive, so plan on replacing the lens after sustained heavy use rather than fighting a declining machine.

Warp on Thin Stock

Blanks under 0.3mm curl when power outruns speed and edge heat concentrates. Drop to 30 to 50 percent power, clamp the blank to a backing plate, or engrave the back face when the front must stay flat.

Ventilation, Workholding, and Lens Discipline

Brass ablation vents zinc oxide, and that fume is not optional to extract. The shield accepts a 240 CFM ventilator hose; run it as close to the head as the hose reaches, and change filters often because zinc oxide loads them fast. Never engrave brass in an unventilated room, no matter how short the job looks.

Workholding decides whether the design survives the pass count. Flat sheets ride on double sided tape or a magnetic base, round blanks sit in a rotary attachment or a shop-made jig, and small parts line up in a shallow aluminum tray lined with masking tape. The point is simple: over one hundred passes, any shift ruins the alignment of the design.

Keep a small bench kit within reach during long sessions: 90 percent or stronger isopropyl alcohol, 400 grit paper, a soft brush, calipers, a spare focusing lens, and anti spatter spray. Before each job, walk a short checklist. The blank is clean and dry, focus is set with the lift column, the red light preview matches the design, extraction is running, glasses are on, and a test square has already run on scrap of the same alloy and thickness. That two minute ritual is the difference between a drawer of test coins and a finished piece.

Applying the Settings to Real Work

Start from the coin recipe when a new job lands: 15000 mm per minute, 20 to 90 percent power, 80 kHz, 1000 dpi, one hundred passes, then the cleanup at 3000 mm per minute, 20 percent, 78 kHz. Treat it as a baseline rather than a law. Red brass wants 10 to 15 percent more power, free cutting stock wants more extraction, and titanium and stainless trade the depth pass for color. Keep the lens clean, keep the fume moving, and keep the blank still. The machine supplies the power, the table in this guide supplies the numbers, and practice supplies the floor smoothness that turns a first attempt into a saleable piece.