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Fri, 6 Nov 1998 09:39:10 -0500 |
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We are evaluating heated, ultrasonic stencil cleaners and liquids.
We are evaluating detergent based liquids, and heating them to 120
deg. F greatly enhances their cleaning capabilities.
We are using no-clean solder paste, type mesh 3, at .020" pitch
components.
I am aware that you must stay below certain temperatures and times at
temp to keep the epoxy from de-bonding from the stencil to the wire
mesh, but, from articles I've read ("...recommend keeping liquid temps
below 110 deg. F"), this seems somewhat ridiculous to me, so I want to
ask:
Is there a concern that temps could
"expand/warp/change pitch/permanently deform" stainless steel (we use
.006") in the fine-pitch or ultra-fine pitch areas?
Any experience you "fine pitch swamis" have would be greatly
appreciated! Thanx in advance!
United Technology Electronic Controls
Jeff L. Hempton, Sr. SMD Engineer
E-mail: [log in to unmask]
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