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Vitronics Soltec Wave Problems

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#50543

Vitronics Soltec Wave Problems | 6 June, 2007

I am experiencing issues with the chipwave of this machine. The solder is not smooth and looks very rippled. I have cleaned the system but with the same results. This condition is leaving me with no-solders. Anyone seen this.

Also should the nitrogen be on when the machine is in idle with conveyor off?

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#50550

Vitronics Soltec Wave Problems | 7 June, 2007

So you are saying that, for a CHIP wave (not the smooth, laminar wave), but the CHIP wave, your expectation is to see "smooth" solder, and not ripply, turbulent solder.

This is what you're saying, correct?

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#50553

Vitronics Soltec Wave Problems | 7 June, 2007

Chip waves are supposed to be turbulant. You have 2 waves, correct? And you're talking about the first wave the board sees, right? What part is not soldering? SOT-23?

Yes you should turn your nitro off when not running the wave.

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#50557

Vitronics Soltec Wave Problems | 7 June, 2007

Man the only ripple i like to see is some fine cognac or hennessey with a 40-oz. as my chaser.

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#50570

Vitronics Soltec Wave Problems | 8 June, 2007

2 waves is correct. While running the glass test panel over the chip wave (1st wave) you can see gaps due to the turbulance. What I did find was the gap of the chip wave was not closing up enough so I adjusted this which made it better. What is the purpose of the turbulance?

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#50572

Vitronics Soltec Wave Problems | 8 June, 2007

Turbulant wave will get into the close quarter areas of your SMDs.

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#50573

Vitronics Soltec Wave Problems | 8 June, 2007

80-90% of an average SM component is non wetable (pushing away solder). So if you would use a single smooth lambda wave (massive amount of molten metal) the negative force of the non-wetable part of the component would be so high that the solder would not reach the solderable part on the side of the component.

That�s why you need certain turbulence in the first wave or additional wave pressure in a single wave to overcome these negative forces.

This can be done with turbulent 1st wave almost splashing solder on the solderable side of the components and pads. Or can be done with a jet wave (thin solder fountain) so the component body sits in air instead of massive metal. Or with a single omega wave (back and forward moving plate in front of the wave) creating enough force and vibration to reach the component solderable sides. Or with a rotating octangle (smart wave) in the front of the main wave creating turbulence and vibrating pressure in the front of the wave.

Double waves have a tendency to create a higher defect rate because:

A)Part of the flux activity is used in the first wave

B)Shorts created in the first (turbulent) chip wave can not always be eliminated by the main wave.

Hope this helps, Patrick

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#50576

Vitronics Soltec Wave Problems | 8 June, 2007

From my past experience, you can usually get away with OUT the chip wave if your SMD's are no smaller that 0805, and more importantly, there are no SOT23's.

A nice, clean, inerted laminar wave (with a little smart or omega help) will solder your SMD's just fine, thus avoiding the additional problems a turbulent chip 1st wave might cause.

Of course, your flux plays a big factor as well in deciding whether to run a dual-wave. A good flux will have enough activity post-chip-wave.

See the fine archives: search keywords VOC-Free flux.

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#50600

Vitronics Soltec Wave Problems | 11 June, 2007

Word!

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