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Solder paste to room temperature.

#33773

Solder paste to room temperature. | 19 April, 2005

I am looking for all the reasons why operators and stores must let solder paste reach room temperature. I am trying to make it is as easy as possible for everyone to understand. I have compiled all the obvious reasons but I am open to all comments and replies. Thanks.

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RDR

#33776

Solder paste to room temperature. | 19 April, 2005

Here is one reason- It eliminates the viscosity change during printing operation from the paste warming up and getting thinner. I would contact your paste supplier and have them give you the full list.

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bobpan

#33777

Solder paste to room temperature. | 19 April, 2005

Try printing while the paste is cold.....you get nothing but bad prints!!!!

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#33780

Solder paste to room temperature. | 19 April, 2005

You should follow your solder paste supplier recommendations. Examples are: * http://www.aimsolder.com/techarticles/tech%20sheet%20paste%20handling.pdf

* http://www.efdsolder.com/PDF/ EFD_-_Frequenty_Asked_Questions.pdf * http://www.ncsmq230.indium.net/PDF/practical_tech_info.pdf

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py

#33796

Solder paste to room temperature. | 20 April, 2005

usual solder cream has a viscosity above 800 000pas at 25�C for each 1�C the viscosity change about 30 000 pas at 15�C you will have nothing ( 37% of viscosity less)on your board...

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Valerie

#33858

Solder paste to room temperature. | 22 April, 2005

Besides poor printing using cold solder paste will also cause solder beading.

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steve

#33863

Solder paste to room temperature. | 22 April, 2005

And don't re-refrigerate the paste. It's fine left out at room temperature and sealed. If you want to know why simply ask and the next 8 respondants will tell you.

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#33879

Solder paste to room temperature. | 25 April, 2005

As Steve said do not re-refrigerate. You can also take the paste out early. We remove enough paste from the refrigerator for a full days work around noon the day before we use it.

Jerry

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#33926

Solder paste to room temperature. | 27 April, 2005

The viscosity decrease on warming is one of the main reasons, but you also don't want to get moisture condensing on the surface of the paste. Activators in the paste (that are used to eliminate solderballs and enhance solderability on reflow) become a lot more reactive if water is present, leading to "concretion", when the paste sets as hard as concrete.

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#33932

Solder paste to room temperature. | 27 April, 2005

is there any relation between solder paste viscosity and the length of time the solder paste being used in the machine? pls advice....

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DasonC

#33989

Solder paste to room temperature. | 29 April, 2005

Moisture will condensed on your paste if the temperature different. Solder bead will happen.

You can see the jar or cartridge wet when you removed your paste from refrigerator.

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