DFM, tolerances and quality
Which GD&T controls matter most on a drawn or stamped part?
Answer
The quoting conversation is easier when the customer states the expected programme length rather than only the annual volume. Tolerances worth calling out Most of a stamped drawing does not need a tolerance; Position of a pierced hole relative to a form, concentricity of a drawn bore to the outside diameter, burr height on a mating face, and flatness of a sealing surface are the ones that decide whether the part assembles. Everything else is general tolerance.
Sources
- Progressive Die Stamping Manufacturer | BalfordThe quoting conversation is easier when the customer states the expected programme length rather than only the annual volume. Chapter 5 — Tolerances worth calling out Most of a stamped drawing does not need a tolerance; a few features do. Position of a pierced hole relative to a form, concentr...
- Deep Drawn Metal Stamping Manufacturer | Balfordthat says “wall 1.0 mm” with no measuring position is not manufacturable as written: the same part can be 1.08 mm at the base of the wall and 0.92 mm at the top. Mark where the wall is measured and what it may be there, and we can hold it. See how wall thickness is specified on a drawn h...
- Automotive Stamping Parts: Clips, Terminals & HousingsStamped and drawn parts are inspected against the drawing, so the drawing is where cost is decided. Three call-outs do most of that work. First, the general tolerance block: if a functional dimension relies on the block rather than on its own tolerance, the process has to be tightened everywhere to ...
- What Is BMW Valvetronic? Variable Valve Lift | BalfordNothing in a variable valve lift system is a low-precision part, but most of it is formed or turned rather than cast: spring seats and retainers are stamped, cups, sleeves and housings are deep drawn and ironed, and shafts, pins and spools are turned and ground. Where a system like this is developed...
- Metal Stamping Tolerances: Reading A Drawing Before QuotingA tolerance block is the table in the corner of a drawing that sets the default limits for every dimension without its own tolerance: normally one band for decimal dimensions, one for angular dimensions, and often a separate line for machined features against formed features. Reading it first decide...
- Industries We Serve | Deep Drawing & Stamping | BalfordIndustries We Serve Deep Drawing & Precision Stamping, Built Around Your Application Every industry we work with sets its own bar for tolerance, material, and finish. Below is how our deep drawing and stamping capability maps onto six sectors we manufacture for daily — with the part types, materials...
What an engineer still needs from you
- material and material condition (grade, temper)
- material thickness, plus the key diameter, height and wall thickness
- tolerances, burr direction and the visual acceptance standard
- annual volume - it decides whether tooling is single-hit, progressive or transfer
- surface finish, and any secondary machining, annealing or plating
Next step. Send the drawing for a manufacturability review, or send the part data for a process and cost route.
Submit a drawing / RFQDFM review
Submit a drawing / RFQDFM review
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This page is an engineering answer, not a quotation and not a dimensional acceptance. It is generated from Balford's published material and held to the verified company fact sheet.