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pasteprinting D.O.E.

pasteprinting D.O.E.

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We want to perform a "design of experiments" session to dete... - Jun 04, 2002 by arzucom

Factors to consider are: * Squeegee speed * Squeegee press... - Jun 04, 2002 by davef

Hello again, Indeed most of the mentioned factors we will ... - Jun 05, 2002 by arzucom

First, I suggest that people search the SMTnet Archives in j... - Jun 05, 2002 by davef

Hi mates, just to add-on, for DOE, also include squeegee ... - Jun 06, 2002 by ianchan

Don't forget squeegee type and angle. (Am I an Ian wanna be... - Jun 06, 2002 by

For solder paste print inspection critera, look here: ... - Jun 06, 2002 by davef

Hussman, What is a Cyber Centry? Who makes it? What doe... - Jun 06, 2002 by davef

Hussman69: "wanna" be is for the spice girls, and I'd cho... - Jun 07, 2002 by ianchan

He ain't no spice girl, I can tell you that!!!!!! ... - Jun 07, 2002 by

Wow, slow down guys. The Cyber Sentry (with an S - sorry)... - Jun 07, 2002 by

arzucom

#20216

pasteprinting D.O.E. | 4 June, 2002

We want to perform a "design of experiments" session to determine the optimum settings for our pasteprinter.We will design a stencil with decreasing aperture-sizes to make it measurable where the printing stops. The result should be a measureable printing quality. We think of : wieght before and after printing, or standaarddeviation of heightdifferences on, say 10 ubga-paste-dots per measurement. Any more suggestions how we can measure quality on pasteprinting?

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davef

#20221

pasteprinting D.O.E. | 4 June, 2002

Factors to consider are: * Squeegee speed * Squeegee pressure * Separation speed * Stencil thickness * Stencil aperture fabrication method * Stencil aperture shape * Paste type * Stencil under-wipe frequency

Search the fine SMTnet Archives for a thread on printing DOE done on CSP by rpereira.

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arzucom

#20234

pasteprinting D.O.E. | 5 June, 2002

Hello again, Indeed most of the mentioned factors we will use as variable parameters, and some of them we keep fixed.

I am interested in the way how to measure results.

Thanks for the hint to dig into former paste-printing threads; I will look at it.

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davef

#20240

pasteprinting D.O.E. | 5 June, 2002

First, I suggest that people search the SMTnet Archives in just about every response that I make.

Second, you need to work on your DOE jargon * Factors. Independent or input variables * Effects. Results. Dependent or output variables.

Third, the results of paste printing are nice looking bricks of paste. Evaluate these bricks in terms of: * Shape * Height * Volume * Area * Registration * Paste bridging

Measure those things with you standard printing process controls. You must use something like: * Microscope is the least costly [$5k] approach, but some would argue that the low price of entry is counter balanced by the need for structure and disciple of results measurement and the poor gauge r&r of the approach. * Laser guided measurement thing is the next level of spending, but some would argue that the relatively high cost [$25k] and lousy gauge r&r make this a dicey investment. * White light measuring tools work very well, but are not priced for the faint of heart.

We have droned on incessantly about paste measurement here on SMTnet. Search the Archives.

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ianchan

#20247

pasteprinting D.O.E. | 6 June, 2002

Hi mates,

just to add-on, for DOE, also include squeegee printing direction as a factor.

Good Luck! happy DOE-ing.

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Hussman69

#20262

pasteprinting D.O.E. | 6 June, 2002

Don't forget squeegee type and angle. (Am I an Ian wanna be or what?)

I'd leave out different types of solder paste.

For measurement, use something like a Cyber Centry. It may cost a little, but if you're serious, it's worth it. Other wise you may want to place and reflow parts and go by what the solder joints look like.

reply »

davef

#20263

pasteprinting D.O.E. | 6 June, 2002

For solder paste print inspection critera, look here: http://www.ppm-monitoring.com/

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davef

#20268

pasteprinting D.O.E. | 6 June, 2002

Hussman,

What is a Cyber Centry? Who makes it? What does it do? What kind of accuracy does it possess? Cost? etc.

reply »

ianchan

#20272

pasteprinting D.O.E. | 7 June, 2002

Hussman69:

"wanna" be is for the spice girls, and I'd choose em' anytime!

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#20273

pasteprinting D.O.E. | 7 June, 2002

He ain't no spice girl, I can tell you that!!!!!!

reply »

Hussman69

#20274

pasteprinting D.O.E. | 7 June, 2002

Wow, slow down guys.

The Cyber Sentry (with an S - sorry) is a machine designed to just measure solder paste height, volume, etc. The first models used a laser, but the newer models are a little more sophisticated than that. They have tabletop versions as well as full blow in line units. I used em in the past but have mixed feeling on their value. They are a great tool for experimenting with, but not sure if I could justify an in line model. I'd rather buy an AOI machine - but that's just my feeling for what we're running today, with the process equipment we use. Tomorrow could change all that.

Their web site is: http://www.cytechnologies.com/produkt_lpast_e.html

Cost, I'm not sure, but I bet you could get a used one fairly cheap these days.

Spice Girls on SMTnet? Hmmmm.....is this a marketing teams dream come true?!

As for that PR fellow, I'm not sure what PC Board he crawled out from under, but you can bet it was all thru-hole!

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