Control of Soldering Irons and Soldering Stations

Hello everybody,

At external audit for ISO9001, we happened to meet an auditor who is a soldering process specialist - he stated the nonformance that we have no control system for soldering irons and/or stations. Can anybody please help me and redirect to any document that suggest WHAT actually must be controlled?
A bit of explanation - the process is soft soldering and its aim is to create electrical connection in wire harness (between wires in multicore cable and legs of a connector); no pull force testing is required, the connection must just hold.

Thanks in advance - Agnieszka

Re: HELP please - control of soldering irons

Do they maintain an in-spec temperature, statically and dynamically?

Re: HELP please - control of soldering irons

What are your requirements? What is required by your customers?

If there is no requirement - it is not a nonconformance.

For example,we do MIG and TIG welding in house. We do not have any requirements from our customers to have welding performed to a specification. Our welders are not certified.

Everytime we are audited - the question is asked "Are your welders certifed?" and my answer is "No, we do not have any requirements to certify our welders or our welding process above what our internal procedures require."

Re: HELP please - control of soldering irons

CarolX said:

What are your requirements? What is required by your customers?

If there is no requirement - it is not a nonconformance.

Click to expand...

No one likes situations where bad production can be "not a nonconformance".

Even if a customer's spec is no more than the word "solder" plus a task-implied minimum-functionality requirement (i.e. tinner copper wires reliably attached to tinner copper terminals with good resulting electrical conductivity), there are some technically implied specifications that must be intelligently met in order for production to be acceptable.

In hand soldering, whatever solder material is chosen for the job, it will have an upper and lower temperature bound during the heated phase to produce electrically and mechanically reliable joints. The joint must be held motionless during cooling. The ratio of flux to solder must be appropriate for the joint nature, i.e. how much solder it requires. The flux must be both appropriate for the work process and post-production operational enviornment, and appropriate for the surface conditions of the materials to be joined and the process's temperature profile.

The iron must have a thermal mass and/or surge energy capability that is appropriate (not too small, not too large) for the job to be done.

The amount of solder and geometry of the joint...even if not to qualified aerospace standards...must be reasonable, i.e. too little or too much, or too weird a geometry, gives rise to legitimate uncertainty as to reliability and quality.

Wave, pot or reflow soldering of course would have totally different specs, implied if not stated.

I'm sure a process expert could discuss this better... but I know from production experience that these requirements exist. If a customer sent us an MR coil electrical assembly job and failed to state one of the above specifications, we would not consider ourselves to be operating in a no-conformance-required zone in regard to that issue. If an auditor decides not to review our actions in regard to some requirement where the customer failed to give us an adequate spec and we filled in the blanks...so be it. We regularly do stuff with a lot of complex interactions between requirements, though, where the auditor has to review our conformance in regard to some customer-specified issue that is dependent on other issues where the customer's requirements are not as well defined. We don't seen it as productive to get into negotiations with auditors over what we were required to do. We'd rather just "do it right", get clean audits and move on to the next job.

Re: Control of soldering irons

Well - first off - I am not electrical expert - not my field - and maybe their auditor is correct....

But without a requirement - whether internal or external - I can't see how there could be a non-conformance.

JMHO

Re: Control of soldering irons

There is a difference between suggesting process improvements and training opportunities, and yelling "nonconformance" and such.

It sounds like the Law of the Plumber: A plumber sees life in terms of pipes and fittings. The auditor (with ethical considerations) can make an observation that they should improve their soldering process. But unless there is a clear requirement for conformance, how can they claim non-conformance? Non-conformities are not sticks to beat people over the head; they need to be about identifying deficiencies in the system.

One should always be about the business of improving how they do things. If there is a solder requirement, then that process should be studied to assure that people have the correct equipment and know what they're doing to generate effective solder joints. Having a solder gun melt solder does not a good joint make.

If the process requires temperature-specific solder tools, then they should be verified that they are operating at that temperature.

Unless the auditor can cite a direct requirement within a possible regulatory requirement or from your own specifications, I'm not sure that it is a legitimate non-conformance.

However.... don't throw away a learning opportunity. By your own statement the auditor is proficient in the area. It's probably reasonable to assume there are several improvements you can embark upon. Don't waste the opportunities. Take them, identify them within your business purposes, and make your process better.

Re: Control of soldering irons

AgnieszkaSz said:

Hello everybody,

At external audit for ISO9001, we happened to meet an auditor who is a soldering process specialist - he stated the nonformance that we have no control system for soldering irons and/or stations. Can anybody please help me and redirect to any document that suggest WHAT actually must be controlled?
A bit of explanation - the process is soft soldering and its aim is to create electrical connection in wire harness (between wires in multicore cable and legs of a connector); no pull force testing is required, the connection must just hold.

Thanks in advance - Agnieszka

Click to expand...

It's always helpful if you give us the exact text of the auditor's finding, including references (if any) to the text in the standard that's (allegedly) been violated. There is a wide range of different soldering equipment available, and there are many different techniques. Someone in your company should have qualified the equipment and techniques, which is what the auditor might have meant by "control."

Re: Control of soldering irons

AgnieszkaSz said:

Hello everybody,

At external audit for ISO9001, we happened to meet an auditor who is a soldering process specialist - he stated the nonformance that we have no control system for soldering irons and/or stations. Can anybody please help me and redirect to any document that suggest WHAT actually must be controlled?
A bit of explanation - the process is soft soldering and its aim is to create electrical connection in wire harness (between wires in multicore cable and legs of a connector); no pull force testing is required, the connection must just hold.

Thanks in advance - Agnieszka

Click to expand...

Soldering is a 'special process' - you can't look at the joint and know it will 'just hold' (and be electrically good too, I hope). So you have to control the conditions under which the joint is soldered, which should really include the soldering iron (someone else has made the point about the upper and lower temperatures).

The auditor was 'off' in their finding, but was trying to be helpful - your organization should be ensuring periodic validation of the irons (putting a thermocouple on the tip and checking the temp. works.).

That would entail a system of marking and maintaining the irons, which is what I would say the auditor is meaning by 'control'.......

Re: Control of soldering irons

This is an opportunity for improvement.

Dear all,

thank you very much for your comments and advice. Yes, during the interview the auditor stated it clearly that soldering is a special process and should be validated as such; this particular NC - about controlling the soldering station - is part of bigger issue which we will have to address.
As for the question whether the stations maintain proper temperature - the answer is, alas - WE ARE NOT SURE. The stations are equipped with temperature indicator and the indications are within limits - but whether this indication is proper, we cannot know without calibrating these thermocouples.
In current circumstances, the soldering stations just exist, without any control - and I believe taht total lack of any control was the direct cause for NC.