Soldertips

Question: To calibrate or not to calibrate, that is the question.

We just purchased new soldering stations and were told that they do not require calibration. While we think that all tooling requires some calibration over time, what am I required to do?

Answer: This is a great question. We are now into Revision F of J-STD-001 “Requirements for Soldered Electrical and Electronic Assemblies”. It was proposed to change the requirement from qualification of the tool to the validation of the tool temperature. Due to the variety of methodologies used to create the heat in a soldering iron, the only important functions of the soldering iron are to verify they can provide the required energy when the thermal demand is required and to maintain its operating temperature within certain tolerances so the iron is working within it operating range. The recovery rate of the iron should also be defined to verify the that the system does not overshoot the top side temperature which would allow a solder joint to be created at a high temperature that may not be acceptable to the product being soldered.

The reasoning for the change was based upon the technology of the new irons in the market and the heat generating techniques employed by the various manufacturers. It was determine to be more important to check the validity of the temperature of the iron as opposed to the calibration of the solder iron. For example the original specification called for the verification of the idle temperature. Based upon conversations with equipment manufacturers and members attending the meetings, no one truly cared what the idle temperature was or is, as it is only being used to extend shelf life of the tip and it cannot be simply measured, because when it is mechanically measured a load is applied to the tip and that is not the idle temperature of the tool. The soldering irons of today go to an idle mode based upon being placed in the cradle being used by the manufacture. This action takes care of extending tip life.

The new revision of J-STD-001 Rev F was released in October 2014 prior to the IPC Midwest show. Appendix “A” Guidelines for Soldering Tools and Equipment.

The major changes were in section A-2 Benchtop and Hand Soldering Systems, (b), (c) and (d).

b. Equipment should be able to maintain control within ±10°C [+18°F] of the selected or required temperature during multiple point-to point or thermal mass on demand soldering operations to verify temperature stability.

c. Temperature stability-degradation to peak (set) recovery temperature – should be periodically checked to demonstrate soldering device can provide temperature control limits defined in Section (b) for multiple load, point-to-points soldering [for example; soldering of a multi-leaded components(s)] or depending on thermal mass demand soldering.

NOTE: Frequency of verification of temperature stability should be dictated by objective evidence of compliance to Section (b).

d. Temperature stability-degradation to recovery overshoot – should be checked using point to point shall not exceed the limits defined in section (b).