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Printing on soldermask

Printing on soldermask

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Hello, We have problems with insufficient solder volume on ... - May 17, 2024 by Yannick Herzog

I almost always go with an overprint as long as it's feasibl... - May 20, 2024 by dontfeedphils

Overprinting - how it's working ? Can you explain ? ... - May 20, 2024 by Michał

Michal, Overprinting is the extension of the stencil apertu... - May 21, 2024 by MagyarT

OK, I know that - I thought there was some other additional ... - May 21, 2024 by Michał

Depends on the product & constraints your having to ... - May 28, 2024 by Carl_P

Can you share which component is giving this problem? Sugge... - May 28, 2024 by kumarb

Yannick Herzog

#90968

Printing on soldermask | 17 May, 2024

Hello,

We have problems with insufficient solder volume on a component.

To solve this problem, we want to add more paste to the component. We have two options for this:

1. run a stencil with a step to achieve the required volume.

2. overprinting the pads, i.e. printing paste onto the solder mask to achieve the required volume.

What is your opinion on this?

I am concerned that solder balls will form when overprinting. How do different solder masks behave?

A stepped stencil causes additional costs.

Thank you for your opinion on this topic!

Greetings

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dontfeedphils

#90973

Printing on soldermask | 20 May, 2024

I almost always go with an overprint as long as it's feasible. I haven't had much problem with solder-balling when overprinting.

I'd give it a try and see how it works for you.

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Michał

#90974

Printing on soldermask | 20 May, 2024

Overprinting - how it's working ? Can you explain ?

reply »

MagyarT

#90975

Printing on soldermask | 21 May, 2024

Michal,

Overprinting is the extension of the stencil aperture over the solder mask, to enable a bigger volume of solder paste on the pad, therefore bigger volume of the solder joint after reflow.

https://youtu.be/WAIm-6BSaiQ?si=UMp9WSFal3vXFp8F as an example.

Regards, Tom

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Michał

#90976

Printing on soldermask | 21 May, 2024

OK, I know that - I thought there was some other additional technology :)

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Carl_P

#91011

Printing on soldermask | 28 May, 2024

Depends on the product & constraints your having to deal with.

I've used the following in the past;

Stepped Stencil, Overprint, Additional dispensing equipment after the print process & Solder pre forms

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kumarb

#91014

Printing on soldermask | 28 May, 2024

Can you share which component is giving this problem?

Suggest to contact the vendor / manufacturer for guidance on the recommended solder paste apertures.

A good company we can recommend on sourcing stencils is Power Stencil in Shenzhen. They build for Intel and many other tier 1 companies. We have had many project stencils built by this shop. Request some advice from them as well.

Also..what about your solder paste? We are now a Koki shop and it is working out very well for us. Any issues we have had were due to not making proper tweaks to the printing profile on our Ekra printer.

Sharing a great contact @ Koki who has devoted most of his adult life to the solder paste process:

Shantanu M. Joshi

Koki Solder America Inc.

6 Kovach Dr. Unit# 614

Cincinnati, OH 45215

(951) 245-8755 Office

(760) 504-2544 Mobile

website: http://www.ko-ki.co.jp/en" target="_blank">http://www.ko-ki.co.jp/en

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