In a message dated 2/26/99 12:21:53 PM Pacific Standard Time,
[log in to unmask] writes:
<< Debbie,
There are several equipment manufacturers capable of building a
conveyorized OSP line. Adam Pill(Germany, represented in this country by ECI),
Eidshun Engineering and FSL, to mention a few.
With respect to the pros and cons of immersion versus conveyorized,
experience has shown that the uniformity of an OSP coating is improved by
conveyorizing. Generally, the uniformity is a cosmetic thing, but important
to some. If you have a high production load, conveyorized equipment should
benefit from a productivity stand point.
Regardless, OSP coatings are thin by nature, and obviously clear in
appearance. In order to insure a cosmetically pleasing and robust
coating(necessary to prevent oxidation of the copper surface) equipment design
is very important.
Best regards,
Michael Carano>>
Hi Debbie!
Michael gave some good information, however, I'd like further amplify the
importance of a uniform coating thickness, and one other reason a conveyerized
process is better. In a water soluble environment where the use of fairly
active fluxes is the norm, variances in coating probably won't give you much
heartburn (unless it's too thin and goes away on the first reflow), but in the
no-clean world where flux activity is pretty lame, I've heard of people having
problems getting good joints because the flux doesn't have enough "ooomph" to
get through the OSP and also clean the metals surfaces.
I've also had the experience from a non-conveyerized shop where they've
done the OSP coating first, then done the bed of nails test (which is bass-
ackwards) merely because of the logistics that it takes to move the panels
around...they kept things in the fab vendors panel size instead of the
production assembly panels because of the number of them (it's easier to move
one big panel than it is to move a bunch of smaller ones), and the bed of
nails tester was set-up to do the larger panels. So I wound-up getting the
panels with a nice divot in the OSP coating...it was a good thing we built
those quickly because I don't think they would've done well sitting on the
shelves for any length of time with a hole in the coating like that...
-Steve Gregory-
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