How to Specify Sheet Metal Edge Finish in RFQs

Engineers often assume that a drawing defines every detail of a sheet metal part. It does not. A flat pattern can show dimensions and hole locations perfectly, yet the edge of the part may still arrive with a burr, a sharp bevel, or a rough cut that fails the next assembly step.

Specifying sheet metal edge finish in RFQs is a practical way to close that gap. When the language is clear, the fabricator can plan the correct operations. When it is vague, the shop may default to a standard finish that does not meet the design intent.

This guide walks through how to describe edge conditions in a way that supports the shop floor and protects the engineering function.

Understand the Edge Conditions You Need

Before writing a specification, identify what the edge must do. Does it need to mate with a gasket? Will a finger touch it during operation? Does it feed into a press-fit?

The function determines the finish. A gasket seat needs a flat, clean surface. A hand-held handle needs a deburred and smoothed edge. A structural joint may only require a burr-free edge to prevent fatigue cracking.

Consider the assembly environment. If the part slides over a steel rod, a rough cut edge will wear the rod and create noise. If the part sits inside a housing, the edge will define the fit. If the part is exposed to the outside, the finish may need to resist corrosion or cleaning.

Write down the specific condition. If the part is for a consumer product, a cosmetic finish may be required. If it is for a heavy industrial application, a functional finish may be enough.

Do not skip this step. It is the foundation of the entire specification. Without knowing the purpose, the technical terms you choose later will be arbitrary.

Define the Base Surface Condition

Start with the raw state of the material after cutting. Most sheet metal edges start as rough cut lines with a small burr on one side and a smooth side on the other.

State the material and thickness. A 1.5 mm steel sheet behaves differently than a 3 mm stainless steel sheet when it is cut. The burr size, the cut quality, and the deburring effort all change with thickness.

If you are using a standard material, you may not need to specify the cut method. If you are using an exotic alloy or a thin foil, specify the cutting process. Laser cutting, plasma cutting, waterjet, and shearing all leave different edge conditions.

Laser cutting produces a clean, thin burr on the top and bottom. Plasma cutting leaves a rougher edge with a larger taper and heat-affected zone. Waterjet cutting produces a very clean edge but can leave a slight roughness on the surface. Shearing produces a clean edge but with a burr on the shear side.

For thin foils, such as 0.5 mm aluminum, the burr is small but the edge is soft. The deburring process must be gentle to avoid bending the edge. For thick plates, such as 10 mm steel, the burr is large and requires a more aggressive deburring method.

Specify the base condition in the RFQ. For example: “Material: 1.5 mm mild steel. Cut edge: Laser cut. Base condition: Standard laser cut edge with minor burr.” This tells the shop where to start.

Specify Bevels and Breaks

A bevel is a small angle cut into the edge. It is used to remove sharp corners, prepare for welding, or reduce stress concentrations.

Define the angle and the depth. A 45 degree bevel is standard in many weldable joints. A 30 degree bevel is often used for cosmetic finishes.

If you do not need a bevel, state that. A “no bevel” note prevents the shop from adding an operation that costs money and time.

Bevels also affect the fit. A beveled edge reduces the cross-section of the part. If the part mates with another part, the bevel may change the contact area. For example, a 45 degree bevel on a 1 mm edge reduces the contact width by 0.7 mm at the top.

For welded joints, the bevel prepares the edge for the weld pool. It allows the welder to access the root of the joint. Without a bevel, the weld may not penetrate fully.

For cosmetic finishes, a bevel creates a softer transition. A sharp 90 degree edge can catch on clothing or skin. A 30 degree bevel is more comfortable.

State the bevel location clearly. “All exterior edges” is clear. “Interior edges” is less clear. “Top edge only” is specific. Use the drawing reference if possible. For example: “45 degree bevel, 0.5 mm depth on edge A on the top face.”

State the Burrs and Sharpness

Burr control is one of the most common sources of dispute between engineers and fabricators.

Use specific terms. “Burr-free” is a good baseline for many functional parts. “Smooth edge” is too vague. “Deburred on all sides” is clear. “No sharp edges” is also useful, but it requires the shop to interpret what “sharp” means.

If the edge will be touched by an operator, specify “smooth to touch” or “no protruding burr greater than a defined size.” For safety-critical parts, reference a standard if one applies to your region.

A burr is a small piece of metal that protrudes from the cut surface. It can be sharp, rough, or smooth. A “burr-free” edge means no protruding material. A “smooth” edge means the surface is flat and even.

For gasket seats, a burr-free edge is critical. A burr can prevent the gasket from sealing. For press-fits, a burr can prevent the part from sliding into place. For safety, a burr can cut skin.

Use a tactile check if possible. Ask the shop to run a finger over the edge. If a burr is present, it will catch. This is a simple test that works well.

If the edge is painted or coated, a burr can show through the coating. The burr may rust or peel. Deburring before coating is usually required.

Describe Surface Texture and Coating

The edge finish interacts with the surface finish. If the part is powder coated, the edge must be clean before coating. If it is anodized, the edge must be free of oil and burrs.

Specify the surface treatment after edge operations. Most shops apply coating after all cutting and bending. If you require a specific edge treatment after coating, state that clearly.

For example, “powder coat, then deburr edges, then final inspection” is a different sequence than “deburr edges, then powder coat.” The order changes the final appearance and the cost.

If you deburr before coating, the edge is exposed to the coating. The coating may cover the burr. If you deburr after coating, you remove the coating from the edge. The edge will be bare metal.

For anodized parts, deburring before anodizing is standard. The anodizing process requires a clean surface. If you deburr after anodizing, you remove the anodized layer. The edge will be bare metal and may discolor.

For painted parts, deburring before painting is common. The paint covers the edge. If you deburr after painting, you expose the bare metal. You may need to touch up the paint.

State the coating type and color. “Powder coat RAL 9005” is clear. “Paint” is vague. “Clear coat” is specific. “Matte finish” is specific.

Write the RFQ Specification Language

Use clear, unambiguous language in the RFQ. Avoid words like “good,” “nice,” or “as needed.” Use measurable terms.

Example:
“Edge finish: Deburred on all sides. No sharp edges. Bevel: 45 degrees, 0.5 mm depth on all exterior edges. Surface: Powder coat RAL 9005, then deburr. Inspection: 100 percent visual check.”

This language gives the shop a clear target. It also gives you a way to verify the part when it arrives.

Break the specification into sections. Edge finish, bevels, coating, and inspection. Use bullet points or a table if the part has multiple edges.

For example:
“Edge A: Deburred on all sides.
Edge B: 45 degree bevel, 0.5 mm depth.
Edge C: No bevel, cut edge as machined.
Coating: Powder coat RAL 9005.
Inspection: Visual check for burrs and sharp edges.”

This structure is easy to read. It is also easy to quote.

Do not rely on the drawing alone. The drawing shows dimensions. The RFQ shows the finish. Together, they define the part.

Common Mistakes to Avoid

1. Assuming the shop knows your intent. Shops have standard practices, but they are not universal. A shop in one region may default to a different bevel angle than a shop in another.

2. Mixing cosmetic and functional requirements. If a part is for a cosmetic application, state that. If it is for a functional application, state that. Do not mix the two without clear priorities.

3. Ignoring the sequence. The order of operations matters. If you require a specific finish after coating, state that. If you require deburring after welding, state that.

4. Using vague language. “Clean edge,” “smooth finish,” and “good quality” are not specifications. They are opinions.

5. Forgetting the thickness. A 0.5 mm edge behaves differently than a 5 mm edge. Specify the thickness in the RFQ.

6. Not defining the cut method. If the cut method affects the edge, specify it. Laser, plasma, waterjet, or shearing.

7. Skipping the inspection method. State how the shop should verify the edge. Visual check, tactile check, or gauge check.

Verification and Inspection

The last step is verification. Before the part is released, run a DfM review with the fabricator. Show them the specification. Ask them to confirm they can meet it.

If the specification is unclear, the shop will ask. If it is clear, the shop will quote it accurately. If it is impossible, the shop will tell you.

Use the verification step to catch errors early. A small change in the RFQ now costs less than a redesign after the part is manufactured.

When the part arrives, inspect the edge. Run a finger over it. Look for burrs, sharp corners, or uneven surfaces. Check the bevel angle with a protractor if possible. Check the coating for defects.

Keep a record of the inspection. Note any issues. Share them with the shop. This builds a feedback loop.

If the edge fails, do not just reject the part. Explain why. A burr on the gasket seat. A sharp corner on the handle. A rough edge on the press-fit. Specific feedback helps the shop improve.

Final Check

Before sending the RFQ, read it from the shop floor perspective. Can a technician read the specification and know exactly what to do? If the answer is no, rewrite it.

A good RFQ specification is short, clear, and specific. It does not need to be long. It needs to be unambiguous.

When you specify sheet metal edge finish correctly, you reduce production surprises. You also build a better relationship with your fabricator. The shop knows what you expect, and you know what you will get.

Edge Condition	Typical Use	Specification Language
Burr-free	Functional parts, gasket seats	“Burr-free on all sides”
45 degree bevel	Weldable joints	“45 degree bevel, 0.5 mm depth”
Smooth to touch	Hand-held parts, safety	“Smooth edge, no protruding burr”
Cosmetic finish	Consumer products	“Cosmetic finish, deburred and polished”
No bevel	Structural parts, cost control	“No bevel, cut edge as machined”