Most etched automotive sensor parts that stall at quotation do not stall on price. They stall on the drawing. Xinketching is a precision photochemical etching manufacturer in Dongguan, China, producing flat etched metal parts since 2005 for automotive sensor, fuel-injection, ADAS and power-electronics applications. The same handful of drawing errors comes back on sensor housings, orifice plates, shielding and contact parts again and again — and every one of them is cheap to fix at design stage and expensive to discover at production. These are the recurring types, stated as process rules, with the fix for each.
Answer capsule: what makes an etched sensor part quotable first time?
- Features sized to the gauge — through-holes and slots at roughly the material thickness or larger (≈0.8–1.2× thickness), not below it.
- Tolerances the process actually holds — ±10% of material thickness as standard; tighter only on dimensions marked critical on the drawing.
- A named material and thickness — grade, gauge and any surface treatment stated, in a metal we etch (stainless steel, titanium, copper, brass, nickel — not aluminium).
- Flat-part honesty — the etched part is flat; any bending or forming is a separate downstream step and must be drawn as one.
Specifications
- Thickness range: 0.05–2.5 mm — gauges 0.05, 0.08, 0.1, 0.12, 0.15, 0.2, 0.25, 0.3, 0.4 and 0.5 mm are stocked; above 0.5 mm up to 2.5 mm is sourced per order
- Dimensional tolerance: ±10% of material thickness (e.g. ±0.02 mm on 0.2 mm stock, ±0.03 mm on 0.3 mm stock); raw-stock thickness tolerance ±0.02 mm
- Minimum through-feature: holes and slots at least roughly the material thickness (design rule ≈ 0.8–1.2× thickness)
- Half-etching: partial-depth features (channels, fold lines, logos, recesses) at ≈50–75% of thickness, depth control ±0.05 mm
- Format: flat sheets only, no coil/reel-to-reel; maximum single sheet 600 × 14,500 mm for material 0.5 mm and above; thinner gauges run in smaller formats
- Finishing: passivation in-house; plating and other surface treatment, stamping and bending/forming via qualified partners where the drawing calls for them
- Lead times and order terms: samples 3–5 days, production 7–10 days; no minimum order quantity, minimum order charge US$100; FOB
- Quality documents: material test certificate with per-run material batch traceability; PPAP Level 3 supported; IMDS data available; NDAs on request
Mistake 1: through-features drawn smaller than the sheet is thick
The most common sensor-part error: a 0.10 mm metering hole drawn in 0.3 mm stock, or a fine slot pattern specified without checking it against the gauge. Etching removes metal sideways as well as down, so a through-feature cannot be etched reliably much below the thickness of the sheet it passes through — the working rule is ≈0.8–1.2× thickness. On 0.3 mm stock the reliable floor is roughly 0.24–0.36 mm; a 55 µm slot in that gauge is not a tolerance problem, it is a geometry impossibility, and we will decline it rather than quote and fail. The fix: choose the gauge from the smallest feature, not the other way round — if the hole must be 0.10 mm, draw the part in 0.1 mm stock and check the part still handles and seals in service; if the gauge cannot come down, the feature must go up.
Mistake 2: a blanket tight tolerance on every dimension
Drawings that tolerance every dimension to ±0.01 mm — including outlines and non-functional hole positions — force a quotation conversation that a marked-up drawing would have avoided. Standard etch tolerance is ±10% of material thickness: ±0.005 mm on 0.05 mm stock, ±0.02 mm on 0.2 mm, ±0.05 mm on 0.5 mm. That already covers most sensor-part geometry. The fix: leave general dimensions at the standard tolerance and mark the genuinely critical dimensions — the metering orifice, the sealing land, the locating holes — as critical on the drawing. We confirm critical dimensions explicitly at quotation, and that is where inspection effort belongs; tightening everything tightens nothing.
Mistake 3: half-etch depths specified outside the process window
Half-etched features — flow channels, fold lines for formed shields, recessed seats — are etched to ≈50–75% of the sheet thickness, with depth control of ±0.05 mm. Drawings that call for a 90%-depth channel, or a half-etch depth toleranced to ±0.01 mm, ask the chemistry for something it does not do. The fix: keep half-etch depths inside 50–75% of gauge, tolerance them at ±0.05 mm, and say what the feature is for — a fold line and a fluid channel at the same nominal depth get reviewed differently (see our half-etching explainer, 2026-10-27).
Mistake 4: drawing the formed part, quoting the flat part
Etching produces a flat part. Sensor shields and clips that arrive drawn in their final bent shape, with no flat development and no fold lines, hide a whole process step: bending and forming are real operations (ours are carried out with qualified partners), with their own tolerances and tooling considerations. The fix: supply the flat pattern if you have it, or mark bend lines and angles clearly on the 3D-derived drawing and expect the flat development to be agreed at quotation. Half-etched fold lines make repeatable bends possible — but only if they are on the drawing.
Mistake 5: an unnamed — or unetchable — material
“Stainless steel” without a grade, or a part specified in aluminium, both stop a quotation. Grade decides corrosion behaviour in fuel, exhaust-adjacent and underbody environments and is a cost driver: 304 is the default, 316L earns its premium in chloride and corrosive service, 301 serves spring-like parts (see our 304 vs 316L vs 301 guide, 2026-10-22). And aluminium is simply not a metal we etch. The fix: name the grade and thickness on the drawing, state any plating or surface treatment the part needs (available via partners; fuel-cell-type coatings are not offered), and if the material choice is open, say so — we will recommend against the service conditions, not against a guess.
When is etching the wrong answer for a sensor part?
When the smallest feature must sit far below any workable gauge, when the part is a deep three-dimensional housing rather than a flat or foldable element, or when volumes and geometry genuinely suit a progressive stamping die and the design will never change again. Etching earns its place where the design is still moving, the features are fine, and burrs or mechanical stress would compromise a sensing or metering function — which is most prototype-to-early-production sensor work.
FAQ
What is the smallest hole you can etch in an automotive sensor plate?
Roughly the material thickness (≈0.8–1.2×). On 0.05 mm stock that is about 0.05 mm; on 0.2 mm stock, about 0.2 mm. Tell us the orifice and the operating conditions and we will confirm the gauge that holds both.
Can you hold ±0.01 mm on an etched part?
Our standard tolerance is ±10% of material thickness, which equals ±0.01 mm on 0.1 mm stock. On thicker gauges, mark the specific dimensions that need to be tighter as critical on the drawing and we will confirm at quotation what is achievable on those dimensions — a blanket ±0.01 mm over a whole 0.3 mm part is not something we will promise.
Do etched sensor parts come with automotive quality documentation?
Yes — PPAP Level 3 is supported, every production run carries a material test certificate with per-run batch traceability, and IMDS data is available. NDAs on request.
What do you need for a quotation?
A drawing or DXF with the material grade and thickness named, critical dimensions marked, quantities (prototype and production if they differ), and any surface treatment specified. Samples run 3–5 days once the drawing is quotable.
CTA: Send your drawing to sales@xinketching.com — Xinketching, Dongguan · since 2005 · xinketching.com
- Photo Etching Tolerances: Why ±10% of Material Thickness Is the Honest Number - October 29, 2026
- Designing Etched Metal Mesh: Aperture, Pitch and Open Area - October 28, 2026
- Half-Etching Explained: Channels, Fold Lines and Logos at 50–75% Depth - October 27, 2026
