"Stamping Very Thin Gauge: 0.1 mm and Below"
Short answer: stamping strip at 0.1 mm and below is possible and common for contacts, shields and spring leaves, but the rules change. Die clearance should be 5–10% of thickness per side, so at 0.1 mm that is roughly 0.005–0.010 mm. Feed must be precise to better than 0.02 mm, strip must be flat and often lubricated, and edge quality falls fast if clearance is wrong. Typical achievable tolerance is ±0.02 mm on a good day, and ±0.03–0.05 mm routinely. Material, not the press, is usually the limiting factor.
Below about 0.2 mm, stamping stops being a force problem and becomes a precision problem. The tonnage needed to shear 0.1 mm brass is small; the difficulty is keeping the strip located, the die sharp and the edge clean, because everything scales down together. This is the territory of contacts, EMI fingers, shims, shields and micro spring leaves, and it rewards planning over brute force.
Why Thin Gauge Is Different
Thinner strip is weaker, flatter, easier to damage and less forgiving of clearance error. It buckles if feeding is inconsistent, curls if the material has residual stress, and tears if the die clearance is even slightly wide. It also conducts heat away slowly, so tool wear shows up as a change in edge quality rather than as a crash. A press that runs thick stock comfortably becomes fussy the moment the coil drops below 0.15 mm.
The core relationships are simple. Shear force scales with thickness, so thin stock needs little tonnage. But the punch-to-die clearance must scale with thickness too, and at 0.1 mm the working clearance is a few microns — a range that demands ground, matched tooling and frequent sharpening. Strip flatness and surface condition also matter more, because a tiny buckle in the coil becomes a dimensional error in the part.
Die Clearance and Tooling for Thin Strip
The single most important number is die clearance. The usual starting point is 5–10% of strip thickness per side, adjusted for material: soft aluminium and brass nearer 5%, harder steels nearer 10%.
| Strip thickness | Clearance per side | Expected burr height | Notes |
|---|---|---|---|
| 0.05 mm | 0.003–0.005 mm | up to 0.01 mm | Very sharp tooling required |
| 0.10 mm | 0.005–0.010 mm | 0.01–0.02 mm | Common thin-gauge range |
| 0.15 mm | 0.008–0.015 mm | 0.02–0.03 mm | Steadier edge quality |
| 0.20 mm | 0.010–0.020 mm | 0.02–0.04 mm | Transition to normal stamping |
| 0.30 mm | 0.015–0.030 mm | 0.03–0.05 mm | Comfortable range |
Indicative values only. When burr height matters, the answer is usually a sharp die and the right clearance rather than a shaving operation. Material choice matters too — phosphor bronze and beryllium copper are common for thin conductive parts because they hold thin sections while still acting as springs, a point covered by the shrapnel spring contact materials guide.
Materials That Stamp Well at 0.1 mm
Not every alloy behaves at thin gauge. The ones that do share fine grain, even thickness and good flatness from the rolling mill.
| Material | Thickness range | Thin-gauge behaviour | Typical use |
|---|---|---|---|
| C2600/C2680 brass | 0.05–0.30 mm | Excellent, soft, clean edge | Shields, simple contacts |
| C5210 phosphor bronze | 0.05–0.25 mm | Excellent spring, holds form | Spring contacts, fingers |
| Beryllium copper | 0.05–0.20 mm | Great spring, costly | High-cycle contacts |
| SUS 301 stainless | 0.05–0.20 mm | Strong, abrasive on dies | EMI cans, clips |
| Aluminium 1100/5052 | 0.10–0.30 mm | Soft, galls easily | Lightweight shields |
Thin strip is usually bought in precision-rolled gauge with tight thickness tolerance. If the mill tolerance on thickness is loose, the part dimension drifts even when the die is perfect, so specifying half-hard tempers and tight thickness tolerance is worth the small price premium — a point covered by the coil stock guide.
Feeding, Flatness and Handling
Thin strip is a handling problem before it is a stamping problem. Feed accuracy needs to be better than 0.02 mm, which usually means a servo feeder with a pilot-release sequence and enough loop control that the coil is never yanked. A mechanical roll feeder can work but struggles at the finest gauge. Strip must enter the die flat; any coil set or camber shows up as a pilot mismatch.
Lubrication is important for a different reason at thin gauge: friction between the strip and the die can pull the part out of location or smear the edge. A light, clean lubricant applied in a controlled film is normal. Wipers and strippers must be sized so they do not mark the strip. And parts must be handled gently after they exit, because a 0.1 mm contact bends under a careless thumb.
Tolerances, Burrs and Inspection
Achievable tolerance on 0.1 mm strip is roughly ±0.02 mm on a well-controlled feature and ±0.03–0.05 mm on general outline. Tighter calls are possible but demand matched tooling, temperature stability and inspection discipline. Burr height must be specified as a maximum, because a loose call will be met with the cheapest edge the die can produce.
Inspection of thin parts is best done optically or with a vision system, since mechanical contact can deflect the part. A first-article report should include burr height, flatness and any critical form angle. When a thin part is also a spring — a common combination in contacts — the load at a given deflection is the real functional check, and it is measured, not assumed. For a wider benchmark of what stamping can hold, see metal stamping tolerances.
How to Design for Thin Gauge
Keep features generous relative to thickness. A bend radius below the strip thickness is asking for a crack; use at least one to two times thickness. Avoid long unsupported spans that will sag or flutter during feeding. Use pilots in scrap areas rather than in the part itself, so the carrier can be trimmed away. Keep the part as symmetrical as possible to reduce curl. And specify the burr direction, because on a thin contact the burr side may need to face the contact surface.
When the part is a fine spring contact or a micro shield, the design often combines thin gauge with tight form control, which is exactly where a source factory with both stamping and spring experience helps. BQUQ runs thin-gauge stamping and custom spring lines in the same Dongguan plant, so the tolerance conversation covers the finished function, not just the blank.
Frequently Asked Questions
Q: Can you stamp metal as thin as 0.1 mm?
A: Yes. We routinely stamp brass, phosphor bronze, beryllium copper and stainless from about 0.05–0.10 mm for contacts, shields and spring leaves, holding roughly ±0.02 mm on critical features.
Q: What die clearance is used for 0.1 mm strip?
A: About 5–10% of thickness per side, so roughly 0.005–0.010 mm for 0.1 mm stock. Softer metals like brass sit near 5%, harder steels near 10%.
Q: Why do thin-gauge stamped parts curl or warp?
A: Usually residual stress in the coil, uneven material flow during forming, or poor strip flatness entering the die. Using precision-rolled strip with tight thickness tolerance and good feed control removes most of it.
Q: How do you control burrs on thin stamped parts?
A: A sharp die and the correct clearance, with burr height specified as a maximum on the drawing. Where a clean edge is critical, deburring happens in-die rather than by bulk tumbling.
Q: Is thin-gauge stamping more expensive?
A: Per-part cost is low at volume, but tooling and process control cost more than for thick stock because clearances and feeds are tighter. Material is a small share of cost; tooling quality is the larger factor.
Related Resources
- Micro stamping parts: how very small and very thin stamped parts are tooled and controlled.
- Metal stamping services: precision thin-gauge stamping with matched tooling and in-house inspection.
- About BQUQ: an ISO9001-certified source factory in Dongguan running stamping, CNC, springs and heat sinks under one roof.
- Contact us: send your drawing and get a quote within 12 working hours.
Authored by the BQUQ Engineering Team. BQUQ is an ISO9001-certified source factory in Dongguan, China, running CNC machining, metal stamping, custom springs, heat sink and collet lines under one roof. Send drawings to sc@bquq.com or WhatsApp +86 13713157787 for a quote within 12 working hours. www.bquq.com
