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Component drop after reflow

Views: 2882

#82888

Component drop after reflow | 25 June, 2019

Dear Everyone, I'm having problem. the Switch component drop after reflow. First, this component placed on top side and through Reflow. Next, the Bottom side is placed component and through reflow. After that, the switch drop and have a gap. We are using Vitronics Reflow, Pls see picture and help me solving this problem.

https://ibb.co/Mky9czM (NG, after bottom side through Reflow)

https://ibb.co/YyqCF78 (OK, after Top side through Reflow)

Rg Sang

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#82894

Component drop after reflow | 26 June, 2019

Do you have any images that show the soldered terminations? Also images of the pcb terminations after the part has moved might be helpful.

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#82895

Component drop after reflow | 26 June, 2019

Have some option to fix it by glue with dispenser? Did you check mby that component touch something inside oven?

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#82898

Component drop after reflow | 26 June, 2019

We are using temperature resistance tape for keeping it. Do you have any other idears..

Rg

Sang

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#82899

Component drop after reflow | 26 June, 2019

There are some pictures of solder and pcb terminal after part has moved.

https://ibb.co/5hKBxXX

https://ibb.co/Kw27cns

https://ibb.co/HtKBMdW

Rg

Sang

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#82904

Component drop after reflow | 27 June, 2019

Maybe you can change the technological process...first assembly top side with small component then bottom with switch...

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SMTA-John

#82906

Component drop after reflow | 27 June, 2019

If the case shield is solderable, add pads to the edge of the two through holes and paste . This wetting should hold it in place.

This message was posted via the Electronics Forum @ SMTASMTA

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#82911

Component drop after reflow | 27 June, 2019

Thank you Pro, We already think about that, but we can not do that because at the top side has big component also.

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#82912

Component drop after reflow | 27 June, 2019

Thank you Pro, Good idea, We will try to do that.

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#82913

Component drop after reflow | 27 June, 2019

It seems to me that it would be easier to manually apply a little bit of chipbonder on the edge of the part after the first reflow than to tape the part down.

The epoxy would cure sufficiently before the second reflow to secure the part after the solder returned to liquidus.

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#82915

Component drop after reflow | 27 June, 2019

Wash the board or do what ever to get rid of flux /flux residue at the parts before running second side. If you can, use special reflow profile for the second side ( Less heat for bottom side).

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#83341

Component drop after reflow | 23 August, 2019

It seems because the soldering area is not enough, so the wetting force is small to hold the switch, remember >0.08g/mm2 for each part as in IPC standard. So, anyway, you need increase the soldering area to reduce weight/area number to below 0.08g/mm2.

And also you need to make sure there's no possibility of centre-of-gravity shift.

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#83398

Component drop after reflow | 6 September, 2019

We use similar switch and the same oven. You need to modify the stencil, increase surface area. Have modified all our stencils to the point where we no longer use inline glue dispensers for any product

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Tor

#83692

Component drop after reflow | 7 November, 2019

Hi Do you know in what and where I can find this in IPC standards

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High Precision SMT Fluid Dispensers

Reflow Oven