What is a servo press?

A servo press uses servo motors for precise force and position control during forming operations.

How do I calculate servo press tonnage?

Use our free tonnage calculator at servopress.club/tonnage-calculator.html

Connector terminal stamping setup on servo

vince_tooldie

We stamp connector terminals and just switched to a servo press. The precision is great but the setup is completely different from our old mechanical. Notes on what we learned.

**Typical Requirements
**
- Part: connector terminals, 0.2-0.6mm phosphor bronze or copper alloy
- Tolerance: ?0.02mm on critical dimensions
- SPM: 200-800 SPM (high-speed applications)
- Die: progressive die, 8-24 stations

**Press Selection Criteria
**
For terminal stamping, direct-drive servo presses are preferred over gear-reducer types:
- No backlash in drive train
- Faster response to motion profile changes
- Better repeatability at high SPM

Recommended: Aida NS series, Komatsu H1F series, or equivalent direct-drive presses.

**Motion Profile Optimization
**
At 400 SPM, each stroke takes 150ms. Typical profile breakdown:
- Approach (TDC to 5mm above material): 60ms at maximum speed
- Forming zone (5mm above to BDC): 30ms at controlled speed
- Dwell at BDC: 5ms (for spring-back control)
- Return (BDC to TDC): 55ms

**Key parameter:** Forming speed in the last 5mm before BDC. For phosphor bronze:
- Too fast (>200mm/s): burr formation, die wear
- Optimal: 80-150mm/s
- Too slow: cycle time penalty

**Feed System Synchronization**

Progressive die stamping requires precise synchronization between press and material feed:
- Feed timing: typically 270-330? of press cycle (feed during upstroke)
- Feed length tolerance: ?0.05mm for 8mm pitch
- Use press encoder output to trigger feed servo

**Quality Control Points
**
- Check first article after every die change: measure 5 critical dimensions
- Monitor tonnage signature —deviation >5% from baseline indicates die wear or material variation
- Burr height: measure every 2 hours, replace punch when burr >0.02mm

lisaQ_metrology

Connector terminal inspection at 400+ SPM requires automated vision. We use a line-scan camera synced to the press stroke counter. Every terminal gets inspected for width, bend angle, and surface defects. Reject rate on the press is 0.02% vs 0.3% on our old mechanical. The servo's consistency makes the vision system's job much easier.

toolndye_dave

Progressive dies for connector terminals are the most precise dies I build. Pilot pin clearance is 0.005mm, punch-to-die clearance is 0.003-0.005mm on the critical features. The servo press's low-vibration operation is essential —on a mechanical press, the impact shock causes pilot pin wear 3x faster.

pressroom_tom

Connector terminals are where servo presses really earn their money. We run phosphor bronze C5191 at 0.25mm and the biggest lesson was getting the motion profile right for the coining stations.

Standard approach: slow approach at maybe 20mm/s for the last 3mm before BDC, then a 50ms dwell at bottom dead center. The dwell is critical for the contact spring features — without it you get springback variation of plus or minus 0.03mm which is out of spec for most automotive connectors. With the dwell we hold plus or minus 0.008mm consistently.

Feed timing is the other gotcha. At 350+ SPM the servo feed needs to complete the pitch advance during the slide retract window, which on short-stroke connector dies is only about 80ms. We had to tune the feed start angle to 190 degrees (10 degrees after BDC) and use the press encoder output directly — not a timer. Any jitter in feed timing shows up as pilot pin damage within a few thousand strokes.

On inspection: agree with the vision system approach. We added a laser micrometer downstream of the press that checks terminal width at line speed. Catches burr buildup before it becomes a quality escape.