Metal buying guides / Fit and processing
What to Send for a Sheet Metal Bending Quote
A bending quote starts with the finished shape, material, thickness, quantity, and dimensions that matter to fit. Include the bend direction and inside radius if it is specified. If a detail is open, identify it for review instead of guessing.
Updated
Quick answer
Send a sketch or drawing of the finished shape, with material, thickness, quantity and inside or outside dimensions labeled. Show which way each bend goes. Let the forming shop confirm the flat size before you buy or cut the blank.
Buying the flat piece before confirming the bend can leave you with the wrong starting size. The bend allowance depends on the material and forming process.
A flange is a bent section extending from the rest of the sheet. The inside bend radius describes the curve on the inside of the bend. A flat pattern is the shape of the sheet before bending.
Show the finished part first
A side view is often the quickest way to explain a simple flange or channel. Mark which direction each bend goes. Include a second view when the shape is not clear from the first.
Label dimensions as inside or outside measurements. For a channel, “2 inches wide” might mean the clear opening or the overall outside width. Those are different requirements.
On a small screen, scroll the table sideways to see every column.
| Detail | Why the shop needs it |
|---|---|
| Alloy or grade and temper | Identifies the proposed material condition |
| Thickness | Affects forming and resulting geometry |
| Bend direction | Distinguishes up/down and left/right features |
| Inside bend radius | Defines the curved inside corner when required |
| Final angle | Describes the formed result |
| Critical dimensions | Shows where fit needs particular attention |
| Quantity | Defines the number of matching parts |
Confirm who develops the flat pattern
The flat length cannot generally be found by adding the outside flange dimensions. Material around the bend must be accounted for. Protolabs explains bend allowance, bend deduction, and tooling-dependent values.
If you have a flat pattern, include it with the formed drawing and state whether it has been validated for the intended process. If you don't have one, say that the flat pattern needs to be developed as part of the reviewed work.
A radius or allowance used successfully at one shop is not automatically the correct value for another shop's tools.
Show nearby holes and hardware
Keep holes, slots, fasteners, and inserts on the drawing even when your immediate question is about the bend. Nearby features may affect forming or assembly. The shop needs the whole geometry to assess the sequence and access.
Identify the visible face if tool marks or cosmetic condition matter. If the part is coated later, say which dimensions must be satisfied after finishing.
For aluminum, use the complete alloy and temper. See 6061 versus 5052 before treating available plate as interchangeable with forming sheet.
Send a clear review request
Please review the attached formed-part drawing, revision B.
Material and temper:
Thickness:
Quantity:
Required inside radius, or radius open for review:
Critical inside / outside dimensions:
Visible face and finish:
Flat pattern: supplied for review OR needs development
Required date and handoff:Leave any unknown dimensions labeled as open questions. The shop can review them with you before the order is agreed.
Send the drawing to Rapid Metals for review of the material, forming, price, and timing. Keep the accepted drawing revision with the quote so the final blank and bend requirements stay together.