Wafer connectors come in both SMT (horizontal, vertical, right-angle) and THT (through-hole, right-angle) types, and the two process families have completely different soldering windows. The plastic that holds the terminals is thermally sensitive, so getting the profile wrong risks cold joints at best or melted, collapsed housing at worst. This article gives the key points for each process so you can set a safe Wafer connector soldering window.
1. SMT Type: Reflow Profile
Wafer bodies are mostly thermoplastic such as LCP or PBT, so keep the peak temperature within 245°C and the time above liquidus at 60 seconds or less to avoid plastic deformation or terminal shift. Use a gentle preheat slope to reduce thermal shock, and verify the soak zone is long enough for the small terminals to heat evenly. A steep ramp is the usual cause of latent cracking at the terminal root.
2. THT Type: Wave and Selective Soldering
For through-hole or right-angle wafers going through wave soldering, confirm the body’s temperature rating and pin coplanarity before the board enters the wave. For heat-sensitive models, switch to selective soldering, which localizes heat and protects surrounding parts. Always verify the standby time and the conveyor speed so the housing never sits in the molten solder longer than qualified.
3. Pad and Stencil Design
- Design SMT pads per IPC-7351, leaving inspection clearance for AOI;
- Reduce stencil openings moderately to limit bridging on fine pitch;
- For vertical types, respect the top no-placement zone to avoid mating interference;
- Match the paste volume to the terminal footprint to control fillet shape.
4. Common Soldering Defects
The usual defects are cold joints from insufficient temperature, bridging from excess solder, offset from poor placement accuracy, and plastic collapse from an excessive peak. Every mass-production first article must be confirmed by X-Ray or cross-section before release, because a Wafer connector hides its joints under a low body where visual inspection cannot reach. Build a defect checklist from the first-article findings and carry it into line audits.
Conclusion: RXSY can recommend the right Wafer package for your process reflow, wave, or selective and provide a temperature-resistance curve with the recommended profile. Contact us for a free cross-reference list against your existing parts.
