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Kester R562 and using lead free components

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MM

#50943

Kester R562 and using lead free components | 6 July, 2007

We are starting to see issues with using Kester WS R562 with lead free components. The joints look grainy on almost all of the 0402'2 and other small components. Some of the solder does not solder to the terminations. These are hybrid boards which means we are using lead paste, with 1/2 lead, 1/2 no lead parts and the pcb is also lead free. I created a hybrid profile to reach a higher temperature than a leaded profile would be, and the joints look better but still some of the solder looks grainy. Has anyone else had this issue lately, could it be a bad lot of solder paste?

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#50944

Kester R562 and using lead free components | 6 July, 2007

What's the metallization on the board? We use an immersion tin board and had to increase our profile to successfully solder.

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#50945

Kester R562 and using lead free components | 6 July, 2007

Krikies! seems like a head-scratcher if I may say so me-self.

I would say the other ogre is right, that surface finish will play a big factor in your solder joint's grain structure or how shiney 'tis.

Non-HASL bearing finishes will typicaly exhibit a bit more graininess than what you're used to seeing, me lad.

A grainy finish doesn't necessarily mean you didn't form a solder joint, i would say.

Also, the fact that you are missing solder on only some of your 0402 terminations would tell this ogre that it's a print, clogged stencil or paste release problems with 0402. You may want to try a 5-mil stencil, me lad.

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