conformal coating over inspection stamps

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Has anyone found a durable, indelible inspection stamp ink? ... - Feb 18, 2019 by Steve Thomas

I have seen this issue with manufacturer markings stamped on... - Feb 19, 2019 by SMTA-Joe SMTA

I figured it was just going to take a little searching to fi... - Feb 19, 2019 by Steve Thomas

Having success with Circuit Boards #432 Solvent Resistant ... - Jun 27, 2019 by SMTA-John SMTA

Steve Thomas

#82022

conformal coating over inspection stamps | 18 February, 2019

Has anyone found a durable, indelible inspection stamp ink?

We have an extreme case of smearing/obliteration because we have the boards dip coated (Humiseal 1B73).

The manufacturer of our stamps is zero help, i.e., the best I could get out of them was "I don't know if we have a ink that will withstand what you are doing" after 3 emails.

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SMTA-Joe

#82036

conformal coating over inspection stamps | 19 February, 2019

I have seen this issue with manufacturer markings stamped on PCBs. The ink just melts away as soon as CC touches it.

This message was posted via the Electronics Forum @ SMTA SMTA

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Steve Thomas

#82037

conformal coating over inspection stamps | 19 February, 2019

I figured it was just going to take a little searching to find a (more expensive) stamp that used an (more expensive) indelible ink. Not the case. Just can't find anything at all, and the stamp manufacturers say not to use any ink but what they provide or the stamps will degrade. I don't know how much truth there is to that but I don't want to destroy any of our inspection stamps just to find out.

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SMTA-John

#82908

conformal coating over inspection stamps | 27 June, 2019

Having success with Circuit Boards #432 Solvent Resistant Ink - Designed specifically for circuit boards. This medium dry ink is highly resistant to solvents .... It is also non-conducting. Note: this ink contains an aggressive solvent so should not be used with plastic stamp pads or stamping equipment with plastic parts. We have metal and felt pads specifically for this ink. This ink is the same as Willmark No. 22. Medium Dry (10-30 secs), this ink gives excellent adhesion to circuit boards and the longer it is left to dry the more resistant it becomes to solvents such as degreasers, fluorinated/chlorinated hydrocarbons, alcohols, and soap and water. (Black, White, colors on special order) #432 Material Safety Data Sheet PLEASE NOTE: THIS INK REQUIRES STAMPS TO BE MADE WITH GUM RUBBER DIES.

This message was posted via the Electronics Forum @ SMTA SMTA

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