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Stencil cleanliness and inspection

#6773

Stencil cleanliness and inspection | 5 June, 2001

We are a high-mix/low-volume operation and end up cleaning 40 - 50 stencils per day. Does anybody know of an automated inspection system or "scanner" that can check a stencil for cleanliness?

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#6774

Stencil cleanliness and inspection | 5 June, 2001

You would be better served to check your print quality as you run. Any problems caused by dirty stencils ( plugged aps etc ) would show up right away as a defect.

Search the forum for more on this subject. I seem to recall the same subject coming up several times in the recent past

Phil

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#6776

Stencil cleanliness and inspection | 5 June, 2001

Thanks Phil.

However, my objective is to identify stencils that are not 100% clean prior to sending to inventory. I want to catch it before the solder paste has a chance to dry and harden in the apertures.

Kerry

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#6778

Stencil cleanliness and inspection | 5 June, 2001

So, yer lookin' to detect a ~25um glob on the wall of the aperture on yer stencil, eh?

Why not wash your stencils before you put them away? That's what we do. Give 'em a quick looksee, then rack 'em, if they're clean. Give 'em anudda looksee before using them.

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#6794

Stencil cleanliness and inspection | 6 June, 2001

Consider running two sets of stencils and washing every four hours.

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#6799

Stencil cleanliness and inspection | 7 June, 2001

Dave,

We have very short runs (less than one hour). We have stencils all over the place waiting to be cleaned. It is too time consuming to scope each stencil to inspect for cleanliness. Do you know of any automated or scanning devices that can rapidly inspect a stencil for contamination?

Kerry

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#6801

Stencil cleanliness and inspection | 7 June, 2001

Kerryn, It's the first time I hear someone who needs an automated inspection machine to check the cleanliness of stencils. Why not improve on the cleaning method itself. I use ultrasonic batch cleaner. It takes 3 minutes to clean a stencil, 2 minutes to rinse and blow dry, and not more than 30 sec to inspect with a jeweler's magnifier (3X).I never had to clean a stencil twice with this method. Even if a machine existed to inspect stencil's cleanliness, just setting up the thing would take at least half an hour. 40 stencil per day at 5 1/2 min each = 220 min, not a problem. Hope this helps.

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#6804

Stencil cleanliness and inspection | 7 June, 2001

I too know of no product like you desire, but I have a lead for you to follow that might get you further than you're getting now.

Call Lumonics [Lumonics, 130 Lombard St, Oxnard, CA 93030 805.485.5559 fax3335 http://www.gsilumonics.com]. They make the lasers that stencil fabs use to cut our stencils.

Also, I believe that they are SMTnet.com advertisers. So, ...

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