Printed Circuit Board Assembly & PCB Design SMT Electronics Assembly Manufacturing Forum

Printed Circuit Board Assembly & PCB Design Forum

SMT electronics assembly manufacturing forum.


Soldering Specification Needed

Views: 7137

A big customer for controller cards is complaining about the... - Sep 23, 2011 by Minda  

#65087

Soldering Specification Needed | 23 September, 2011

A big customer for controller cards is complaining about the quality of the soldering on our PCBs. The photographs they sent were very unreasonable, pointing out minor defects such as tiny (tiny as in smaller than the point of a pin) drips of solder on the green part of the board and a small piece of lint that could have gotten on the board at any time. I have attached a picture of the worst "drip".

We inspect the cards before shipment to ensure they are working properly, so we feel that the quality issues the customer is complaining about are no more than attempts to lower the price. The problem is this: we do not have any sort of standard or specification we both agree on regarding these quality concerns.

I have scoured the internet and cannot find any sort of MIL-SPEC or ISO or any other standard that we can use regarding the quality of the circuit boards. We are content with the quality of the product because it does what it is designed to do and does it well. Perhaps someone out there can share a link or something where I can get some resources?

Thank you so much!

Attachments:

reply »

#65088

Soldering Specification Needed | 23 September, 2011

IPC-A-610E "Acceptability of Electronic Assemblies" addresses this specific issue as well as most others. This issue would be to what class (1, 2, or 3) your assemblies would be governed by.

reply »

#65089

Soldering Specification Needed | 23 September, 2011

I found IPC-A-610E, but I cannot find one online that I can view without purchasing. We do not want to pay for a standard we are not sure we will be able to use.

reply »

#65090

Soldering Specification Needed | 23 September, 2011

Put the ball in their court and ask them to send you what specifications they are inspecting to.

reply »

#65091

Soldering Specification Needed | 23 September, 2011

I found some useful information in a red line version of IPC-A-610E I uncovered with a quick google search, and I will see what I can find out about their standard of acceptability.

reply »

#65092

Soldering Specification Needed | 23 September, 2011

A solder drip like that is completely unacceptable. That could easily short two QFP leads. Very poor quality. Your customer is right to be upset. You need to pony up the money for IPC-610, agree with your customer to which level you're working (1, 2, or 3).

reply »

#65093

Soldering Specification Needed | 23 September, 2011

The IPC-610 class II spec is very reasonable. If they expect class 3 then make them pay for it....IMO

reply »

#65094

Soldering Specification Needed | 23 September, 2011

What are the differences between the classes? Essentially we solder the components onto the board, test them, and ship them out so this is all a learning experience for me as the new QE on board.

reply »

#65095

Soldering Specification Needed | 23 September, 2011

The small investemnt of purchasing the IPC-610 manual will pay for itself very quickly. A brief description of the two classes in a few words would be the following: Class II - a well built product with reasonable expectations for both the manufacturer and the consumer. Class III - nit picking and overkill in a lot of cases by the purchaser, price will be or should be much higher for this service.

Have a good weekend!

reply »

#65096

Soldering Specification Needed | 23 September, 2011

Haha, thanks for the information.

The standard is ordered and downloaded. I will begin reading Monday morning.

reply »

#65104

Soldering Specification Needed | 26 September, 2011

Hi Minda

Customer is always right and u hve to follow their standard if they dun agree with ur company quality standard. Even u follow IPC standard, u can't do nothing unless ur customers agree with it. B4 get orders, ur sale and customers must discuss about ur company quality.

Good Luck

reply »

#65105

Soldering Specification Needed | 26 September, 2011

Basically in loose general terms:

IPC class 1 is for consumer products that you discard when they break.

IPC class 2 is for industrial products that last longer than class 1 products and you can repair when they break.

IPC class 3 is for military and medical products where failure of the assembly is not an option.

reply »

#65107

Soldering Specification Needed | 26 September, 2011

So you are saying that building to class III is going to prevent failures? I disagree. Class III is trying to hit target condition in every aspect of the production of the circuit board.

That my friend does not ensure failures from happening.

I see workers touching-up class II defects with solder irons on a routine basis. Though the solder joints may look somewhat cosmetically better after the rework, the parts are now may be comprimised after being resoldered with a 700 deg F iron numerous times until it looks pretty.

Here's the deal, if your customer doesn't tell you what spec to follow than you tell them that you build to IPC-610 class II as a company standard. If they want class III then tell them Ok, but we are going to have to requote your assembly(s). Then charge them accordingly.

reply »

#65108

Soldering Specification Needed | 26 September, 2011

I agree that class III is overkill for most applications and the customer needs to pay for it if that's what they want.

It's also true that class III doesn't assure things won't fail. Life expectancy is mostly due to component and material selection.

We're in the high reliability market and we build to class III, but we don't get their by repairing until they cosmetically meet class III. In fact, we don't allow repair on many of our products. We design and run our processes to turn out class III day in and day out, millions per year.

reply »

#65110

Soldering Specification Needed | 26 September, 2011

I am happy that you work in a shop that can build boards right the first time on a consistent basis. Unfortunately, I would say that every place I have been at, we have had a hard time meeting class III standards day in and day out without some kind of rework. Especially when it comes to soldering wires onto pcb's and certain wave soldering applications. Hopefully someday we get there though. Most of our orders are between 10 and 100 pc builds, so we will never hit the million mark.

reply »

#65112

Soldering Specification Needed | 27 September, 2011

I did not mean to imply building to class III would prevent failures. Since there seemed to be a little confusion about the classes I threw that out to show that class III was a higher standard. I also agree that while re-work can fix a class III defect, it might also do more harm than good for reliability of the product.

It all comes down to building it right the first time (as much as possible) to whatever specification the customer requires and making them pay appropriately for the level of specification.

reply »

#65113

Soldering Specification Needed | 27 September, 2011

Is it correct that there is nothing direct in Class III documentation that states these boards should not be reworked? Whether these boards are allowed to be reworked is strictly a decision / agreement between assembler and customer . . . correct?

reply »

#65114

Soldering Specification Needed | 27 September, 2011

That's correct - IPC-610 doesn't tell you whether rework is allowed or not. That's a customer issue.

reply »

#65123

Soldering Specification Needed | 28 September, 2011

And of course IPC has IPC 7711/7721 that covers rework, repair, and modification of electronic assemblies.

reply »

#65124

Soldering Specification Needed | 28 September, 2011

If I were Mr. Customer, I'd be more concerned about that "globby" looking solder fillet on R3.

I would then ask you to provide a profile.

reply »

SMT Equipment Online Auctions

SMT Equipment Service