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Wet or Dry Wipe

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Jim

#38821

Wet or Dry Wipe | 4 January, 2006

What is the preferred method of under stencil wiping? (Wet or Dry wipe)

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#38822

Wet or Dry Wipe | 4 January, 2006

Wet wipe could allow solvent through the apps and into the paste. For this reason I never never never use wet wipe.

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Rob

#38827

Wet or Dry Wipe | 5 January, 2006

We use dry for everything. There used be be a corroding problem with the fluid for wet wiping, but I'm sure they must have solved that by now.

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URL

#38828

Wet or Dry Wipe | 5 January, 2006

Assuming you mean paste and not adhesive, we use both wet and dry with vaccum. We can control the solvent thru the software for each job, so no solvent sprinkling thru the stencil. Never head of corrosion on stainless steal, but then again I'm sure a lot of people use some goofy materials out there.

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Rob

#38833

Wet or Dry Wipe | 5 January, 2006

It wasn't corroding the stencil, it was corroding the cleaning fluid system.

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URL

#38847

Wet or Dry Wipe | 5 January, 2006

Corroding the cleaning fluid? OK I still don't under stand? Does your screen printer recycle the fluid and the paste is mixing with it?

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Rob

#38861

Wet or Dry Wipe | 6 January, 2006

Sorry for not being clear, still not out of hibernation yet - the cleaning fluid was corroding the cleaning fluid delivery system - the resoviour, pipes etc, and where spilages happened the actual machine.

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URL

#38863

Wet or Dry Wipe | 6 January, 2006

Oh, got ya. Ouch, that had to suck. Do you mind telling us what you used and what it attacked?

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Rob

#38864

Wet or Dry Wipe | 6 January, 2006

It attacked our lovely AP25's, can't remember exactly what the fluid was as it was a loooong time ago now, but it was definelty specified by a telecoms OEM.

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#38865

Wet or Dry Wipe | 6 January, 2006

Yes, that's why wiper system metal material has been changed to stainless steel. There is an approved solvent list on the Speedline Tech web site. Go to:

http://www.speedlinetech.com/news_publications/application-notes.aspx?OnId=5

Then go down to MPM and find Solvent Study Released...

On Wet/Dry, depends on application. You can do wet to losen material from aperture walls, then dry to final wipe. Its best with a vacuum system though.

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PWH

#38869

Wet or Dry Wipe | 6 January, 2006

We had a bad situation with solvent wipe. One of the solvent supply lines cracked and the solvent got on a cluster of air lines. The air line material reacted poorly and we blew what seemed like one airline per day for a couple weeks. I had to cut and splice the ruptures. There is a plexi-glass cover over a circuit board in this vicinity that surely would have been ruined had it not been covered. I'm not saying solvent wipe is bad - just throwing out a caution on what bad things can happen and what you want to inspect for during maintenance. Can't remember what kind of solvent we were using at the time.

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#38894

Wet or Dry Wipe | 9 January, 2006

When I had that luxury I always used a double pass, first wet then dry, to reduce the amount of wet solvent left on the stencil. That also gives it some time to evaporate. If you've got suction I don't know how you'd ever get any through the apertures unless you're really pouring it on.

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