304 Stainless Steel sheet metal

304 Stainless Steel: Frequently asked questions and fabrication deep dive

304 stainless steel is one of the most widely used metals in the world, prized for its corrosion resistance, durability, and versatility in fabrication. At SendCutSend, 304 is one of our most popular stainless options for laser cutting, available in 10 thicknesses from .030″ up to .500″. If you’re designing parts for laser cutting and fabrication, understanding how 304 behaves will help you get better results on the first try. Below we’ve put together a deep dive into the most commonly asked questions about 304 stainless steel, optimized for both engineers and makers.

Key things to know about 304 stainless steel

• 304 stainless steel is versatile, strong, and corrosion-resistant.
• It cuts extremely well with fiber lasers.
• Expect ±.005″ tolerance and follow design guidelines for best results.
• 304 is weldable, formable, and machinable, though springback and work hardening should be considered.
• Its main limitations are chloride corrosion and high-temperature scaling.
• SendCutSend provides laser cutting, bending, and finishing services with industry-leading speed and precision.

What is 304 stainless steel?

304 stainless steel is an austenitic chromium-nickel alloy that belongs to the 300-series of stainless steels. It’s considered the “workhorse” of stainless, making up over half of all stainless steel produced worldwide.

Composition

• Chromium (18–20%): Provides corrosion resistance and a passive oxide layer.
• Nickel (8–10.5%): Improves toughness and ductility.
• Iron (balance): Base metal.
• Small amounts of manganese, silicon, and carbon.

Properties

• Yield strength: ~30 ksi (205 MPa).
• Tensile strength: ~73 ksi (505 MPa).
• Elongation: ~40% in 2″.
• Hardness: ~HRB 80 (annealed).
• Density: 0.289 lb/in³.

Variants

• 304L: Low carbon version, better for welding (less risk of carbide precipitation).
• 304H: High carbon version, improved strength at elevated temperatures.

Want to compare? Check out our 316 stainless steel page for applications where chloride resistance is critical.

Can 304 stainless steel be laser cut?

Yes 304 stainless is one of the best candidates for fiber laser cutting, the process SendCutSend uses.

• Fiber lasers excel at cutting reflective metals like stainless.
• With the right assist gas and parameters, laser cutting produces clean, precise edges on 304 stainless.

At SendCutSend, we hold a cutting tolerance of ±.005″ on stainless steel, which makes it an excellent choice for parts requiring tight fitment. For more detail, see our laser cutting guidelines.

What edge quality issues should you expect when laser cutting 304?

Stainless generally cuts cleanly, but a few issues can crop up if not optimized:

• Burrs and dross: Usually caused by incorrect gas pressure or feed rates.
• Discoloration / heat tint: Cosmetic only; can be removed with finishing.
• Warping: Thinner sheets may distort under heat, especially with large cutouts.
• Heat-affected zone (HAZ): Minimal in laser cutting compared to plasma or torch.

Gas choice matters:

• Nitrogen cutting: Produces bright, oxide-free edges. Preferred for stainless.This is the process SendCutSend uses on our 304 stainless parts.
• Oxygen cutting: Faster but leaves an oxidized edge, less suitable for cosmetic parts.

How does 304 stainless behave when bending?

Bending 304 stainless steel is very doable, but it requires some planning compared to bending mild steel or aluminum. At SendCutSend, we bend 304 every day on our CNC press brakes, so here’s what you need to know when designing for stainless bends.

Key characteristics of 304 when bending

• High ductility: 304 is an austenitic stainless, so it can bend without cracking when the bend radius is appropriate.
• Springback: Expect more springback than with mild steel or aluminum. The material wants to “relax” back toward flat after bending. Our press brakes automatically compensate for this, but you should plan your design accordingly.
• Work hardening: As it bends, stainless steel gets harder at the bend line. This makes sharp bends harder to achieve and increases tool wear.

Recommended bend radii for 304 stainless 

• The minimum inside bend radius should be at least equal to the material thickness for most applications.
• Tighter radii can cause cracking, especially in thicker gauges.
• For heavy gauges (.250″+), we recommend using 2–3x material thickness for the inside radius.

Flange length and bend spacing

• Minimum flange length: At least 3x material thickness, so the press brake tooling can grip and form the bend accurately.
• Bend-to-bend spacing: Keep bends at least 2x material thickness apart unless otherwise planned for special tooling.

Bending tolerances

• Because of springback and tool clearances, expect some variation in bend angles if not properly compensated.
• At SendCutSend, we hold tight bend tolerances by using precision tooling and CNC-controlled presses.

Design tips for bending 304 stainless

• Use consistent bend radii across your design to simplify tooling and improve repeatability.
• Orient your bends with the grain direction of the sheet in mind. Bending across the grain reduces cracking risk.
• If you need multiple bends in close proximity, confirm they fit within our bending design guidelines.

Why outsource bending to SendCutSend?

• Precision press brakes: Our machines compensate for springback and hold tight bend tolerances.
• One-stop process: We laser cut and bend in the same workflow, so hole-to-bend alignment is consistent.
• Fast turnaround: You don’t have to ship parts to multiple shops. Cutting + bending is done together, shipped in 2–4 days.
• DFM guidance: Our team reviews parts for bendability before cutting, so you won’t end up with parts that can’t be formed.

What are the limitations of 304 stainless steel?

• Chloride environments: Susceptible to pitting and crevice corrosion.
• High temperatures: Loses strength above ~1600°F.
• Cost: More expensive than mild steel or aluminum.

If you need superior corrosion resistance, consider our 316 stainless.

What finishing options are available for 304 stainless after laser cutting?

SendCutSend ships stainless steel parts with a mill finish by default, which is the raw, as-rolled finish from the mill. This finish is perfectly functional but may show light scratches or surface marks from handling. If your project calls for a cleaner or more decorative look, we offer several finishing options:

Mill Finish (No Finish)

• Fastest, most economical option.
• Parts ship as-cut with the natural mill scale and laser cut edge.
• Expect light scratches or scuffs — common for raw stainless.

Tumbled Finish

• Vibratory tumbling removes sharp edges and small burrs.
• Produces a smooth, matte surface that’s safer to handle.
• Good for functional parts where appearance is secondary to comfort and safety.

Brushed Finish

• Creates a uniform, linear grain across the surface.
• Ideal for visible panels, enclosures, or decorative projects.
• A popular choice when a “clean stainless” look is desired.

Powder Coating (Available at SendCutSend)

• Powder coating provides a durable, protective layer that also adds color.
• Much tougher than liquid paint: resistant to scratching, chipping, and wear.
• Available in a wide range of colors and textures to suit functional or decorative parts.
• Also adds an extra layer of corrosion resistance, which is helpful if parts will be exposed to moisture.
• Excellent option for branding, aesthetic appeal, or added durability.

Passivation (Post-process option outside of SendCutSend)

• A chemical treatment that restores the chromium oxide layer on stainless after machining or welding.
• Improves corrosion resistance in demanding environments.
• Not offered in-house by SendCutSend but worth considering for critical aerospace, medical, or marine parts.

Polishing & Electropolishing (Custom, not standard at SendCutSend)

• Mechanical polishing or electropolishing produces a mirror-like, highly reflective surface.
• More common for architectural or food-grade applications.
• Not part of our standard finishing services, but compatible with laser cut stainless parts.

What tolerance and accuracy can be expected when laser cutting 304?

At SendCutSend, we hold ±.005″ cutting tolerance across stainless thicknesses up to 0.500″. For more detailed specs on each thickness, check the material specifications section of our catalog.

What are best design practices for laser cut 304 parts?

• Respect minimum feature sizes: Webs should be at least material thickness.
• Avoid excessive heat build-up: Space out dense cut patterns.
• Account for bend allowance: Stainless has high springback.

For all minimums and maximums, see our design guidelines.

How long does it take to laser cut 304 stainless?

At SendCutSend, standard lead time for stainless steel parts is 2–4 business days before shipping, regardless of thickness. Learn more about how we process parts in our instant quoting system.

How do environmental conditions affect 304 stainless performance?

• Outdoor exposure: Excellent in non-marine environments.
• Marine/coastal exposure: Susceptible to chloride attack.
• Industrial chemicals: Acids and chlorides accelerate corrosion.

For more demanding corrosion resistance, see 316 stainless.

How can you identify or verify 304 stainless steel?

• Magnet test: Generally non-magnetic.
• Chemical spot tests: Detect nickel content.
• XRF analyzers: Most reliable.
• Mill certs: Available upon request.

What post-cutting services are available for 304 stainless steel at SendCutSend?

Laser cutting is just the start. To save you time and keep your parts production-ready, SendCutSend offers several add-on services for 304 stainless steel:

Dimple Forming

• Dimple forming creates a raised, conical “flare” in the material to strengthen holes or provide clearance for fasteners.
• Commonly used for countersunk screws or to reinforce mounting points.
• Helps thin-gauge stainless handle loads without distorting.

PEM Hardware Insertion

• We install PEM fasteners (self-clinching nuts, studs, or standoffs) directly into your laser cut stainless parts.
• Provides strong, reusable threads in sheet metal without the need for welding or secondary machining.
• Great for enclosures, brackets, or assemblies that need multiple fastener points.

Tapping (Threading Holes)

• We can tap holes directly into your stainless parts after cutting.
• Saves you the hassle of secondary machining or hand tapping.
• Compatible with a wide range of thread sizes — check our tapping guidelines for supported specs.

Why use SendCutSend for post-cutting services?

• One-stop workflow: Cutting, bending, tapping, and hardware installation all happen in the same shop.
• Precision alignment: Holes are cut and tapped in a single process, so everything lines up perfectly.
• Time savings: No need to send parts to multiple vendors — you get finished, ready-to-use components straight out of the box.

What is the maximum usable temperature for 304 stainless?

• Continuous use: ~1600°F (870°C).
• Intermittent use: ~1700°F (925°C).
• Beyond these ranges, 304 can scale, lose strength, and suffer carbide precipitation.

When should you cut 304 yourself vs. outsource to SendCutSend?

Cutting 304 yourself

DIY cutting is possible with the right equipment, but stainless is tough:

• Reflective, difficult for CO₂ lasers.
• Abrasive to tooling, hard on consumables.
• Heat distortion and burrs common with plasma.

Outsourcing to SendCutSend

• ±.005″ tolerance on all cuts.
• Clean, oxide-free edges with nitrogen assist gas.
• Fast turnaround — parts ship in 2–4 days.
• Optional services like bending and finishing in the same workflow.

For most makers and engineers, outsourcing to SendCutSend is faster, more cost-effective, and higher quality than trying to cut 304 yourself.