Fifo of Solder Paste

what about tube (could be transparent) with opening at the bottom to pick up by operator and loading new fresh jars from top (vertical tower of solder jars). Each time when operator takes jar next one appears on the bottom etc.

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Can you have an outside vendor source it for you? Kind of like an "in house store". Besides paste, they would also supply you with all your other "dated" material. That way you only get charged for what you use. Then make sure your operators check the date before use. This puts the pressure on the in house store guy - not you. They can also handle all your little hand tools, brushes, and things like that. They woudl store everything in yout plant but would regulate it. It's not hard to do and pays for itself every year. We tried it and are hooked on it. Works very well.

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I've done it 3 different ways in my career (3 different places):

1.) Process Engineering was responsible for solder paste inventory (as well as all other process materials). That was a bad situation due to the blame factor.

2.) TOOL-CRIB control. This was a great situation actually. The Tool-Crib personnel were solely in charge of FIFO and issued paste to the lines...signed and dated. They also ensured adequate thawing and adhered to solder paste management guidelines.

3.) In-House Stores (see Chunks post).

I would also delve deeper into the "unrefrigerated shelf life" guideline for each of your solder paste suppliers. You'd be surprised....it's actually a bad thing to "re-refrigerate" solder paste. Leave it at room temperature, but make sure it's in an air tight container. It can be left at room temp. for up to a month. My only caveat here is...for those who don't have temp/RH controlled shops, you might need other equipment (like a Nitrogen cabinet).

Ultimately, FIFO is a discipline thing. At my current place, it is ISO mandated and the operators can get dinged if they're caught not following FIFO rules and paste management guidelines.

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It depends on the usage , if it is regular and steady, only order when needed , we only order 2 jars when the last one is taken out of the fridge.One jar would last us about 2-3 weeks and it stays on room temperature. Ofcourse , you need a realiable supplier and an accurate reorder system , we use kanban it works fine

By the way , CK Pb-Head , what can go wrong if you "re-refrigerate" solder paste, any experience ??

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Thanks for all the ideas and suggestions. One other side question. Does anyone have any experience of, or have any views on Paste conditioners? Basically the paste is removed from fridge and spun for 7 minutes or so then is ready for production.

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