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Stencil Cleaning by hand

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#66942

Stencil Cleaning by hand | 3 August, 2012

Greetings everyone, I am trying to figure out away to clean our stencils by hand. Unfortunately, we do not have a stencil cleaner due to size and finance of our company. I am using Ionox to clean them daily.But the walls do not come clean. Is this a humidty related problem for Pb-Free solder, anyone experiencing this? Also, I am using Indium8.9 Pb-free type3 SAC and clean the stencils with Ionox I3400. Any help willl be deeply appreciated.Thank you in advance.

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#66943

Stencil Cleaning by hand | 3 August, 2012

Not the best situation in the world, but you know that.

Check with printer equipment suppliers [eg, DEK, MPM, etc] for a product called "Stencil Clean Wipes."

Back in the old days, we'd: * Wipe the stencil with a solvent soaked wipe * Put the stencil in a bin filled with some liquid * Move an electric powered vibrating box over the top of the stencil to loosen the paste that had dried and bonded itself to the apertures I've lost track of the company that supplied the vibrating box thing. [Although, if we let our mind wander we might be able to suggest possible alternative. My computer can't access some of those sites.]

Other suggestions: * For starters, you might consider increasing your cleaning frequency. Cleaning 'daily' might be just a bit too long between cleanings. * Can you rent [rent-to-buy] a stencil cleaner?

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#66952

Stencil Cleaning by hand | 6 August, 2012

You might want to look at a hand held ultrasonic stencil cleaner such as this one from Gen3 http://www.gen3systems.com/viewprod-GENSONIC.php *note i do not work for gen3 but they are a rep for other products my company produces

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#66953

Stencil Cleaning by hand | 6 August, 2012

Thank you Dave, As always you provide us valuable information. I will try that to see how it works.

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#66954

Stencil Cleaning by hand | 6 August, 2012

Thank you Jeremy, That might be the solution. I will contact them.Best regards. Aybars

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#66955

Stencil Cleaning by hand | 6 August, 2012

Techspray makes a liquid called "Eco-Stencil SMT Stencil Cleaner" and also pre-saturated wipes by the same name.

We spray the cleaner on the stencil and then use the wipes to clean the paste off of the stencil. Putting 1 wipe in each hand and rubbing both the top and bottom of the stencil at the same time has worked well for us. We clean the stencil as soon as we are done using it so that the paste does not have time to dry on the aperture walls. The cleaner dissolves the solder paste so if the paste is dried on you will need to let the cleaner soak on the stencil a few minutes to soften the paste.

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#66963

Stencil Cleaning by hand | 7 August, 2012

wipes + IPA (isopropyl alcohol) can bring good result to you.

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#66970

Stencil Cleaning by hand | 7 August, 2012

Thank you for all your inputs, I was thought not to use alcohol on stencil (Since it is a drying agent and reaction to Cu solidification), Am I wrong? Regards,Aybars

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#67041

Stencil Cleaning by hand | 17 August, 2012

I would advise against using IPA for stencil cleaning It may initially seem to produce good results but the way it works you end up with more problems. IPA is good at removing liquid fluxes but it dries out and cements solid fluxes to the stencils. I have seen a stencil that was cleaned after every use with IPA and looked at some of the apertures under a microscope and it looked like tree rings of solid flux. Specific stencil cleaning fluids are designed to remove both liquid and solid fluxes

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