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Shorts & Dry Joints

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#66971

Shorts & Dry Joints | 7 August, 2012

Hi All

Im new to the forums, And this my first thread.

im the production manager at Broyce Control

Everything ive learnt about wave soldering is by trail and error i know its not the best way but it has worked for me.

The problem i have been having is shorts and dry joints.

What could the cause be for shorts and dry joints, can anyone recormend any flow solder setting i can try one my machine

PCB Thickness is 1.6mm Flowsolder Machine; Blundell Lead Free Flux Type; 35-92 BLT

Please have a look at the attached PDF file.

Attachments:

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#66973

Shorts & Dry Joints | 7 August, 2012

It looks like the inside of the barrels on these holes are not plated. Check some raw PCBs and see. If not, solder isn't going to flow to the top or make anything resembling a good solder joint.

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#66974

Shorts & Dry Joints | 8 August, 2012

Thanks hoss67 for your reply, the PCB is single sided, not double sided.

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#66978

Shorts & Dry Joints | 8 August, 2012

The boards are being soldered in the wrong direction. Rotate them 90* and your problem will go away.

To demonstrate this further, rotate the board 180* and observe that the problem moves to the opposite side of the connector.

I assume that in the first picture, in the red circled two columns of pins, in the right-hand column of pins that the top pin and the second from the top pin are intended to be shorted together, by a sloppy designer. Right?

Further, virtually every picture of a board shows voiding in the solder connections. Consider steps to reduce this issue.

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Voidless Reflow Soldering

Fluid Dispense Pump Integration