John:

Dave surely points out the crucial factors about graphic design, roller
saddle and clip problems, but I would like to add my two "pragmatic" cents.
In a small shop I worked before, they tape three or four cores in series
after a leader board like a train.  They run this way through old Marseco
etcher and stripper with almost no scrap.  Also tape all the way along the
sides instead of just taping a few spots.

But when you go down to 2 mil core, It depends a lot
on the board design.  Half oz Copper runs easter than 1 oz foil.  Most of
the time the cores were ripped first.  Jam-up is only the consequence.

For the conveyor system, dead rollers are the number one killer for the
cores.  That is where you get cores jammed.  Make sure all the gears are
working.  Personally I believe that roller only conveyor systems work better
than roller and clip systems.

Yu-Shan Han
Lead One Technology, Inc.
(206) 368 - 8429


----- Original Message -----
From: Dave Brown <[log in to unmask]>
To: <[log in to unmask]>
Sent: Wednesday, February 09, 2000 10:58 AM
Subject: Re: [TN] Thin Core Processing


> John,
> Assuming you cant correct the cause to the jam-up(older DES line) you may
want to try
> the following.  The copper border around the core can be utilized as a
frame (keeping
> in mind you need some clearances for prepreg flow.  Taping leaders is the
other method
> (time consuming, handling etc).  If time and money allows, you could
review your DES
> line transport system.  Perhaps the saddles for the conveyor rollers are
worn causing
> some rollers to sit lower then others or the roller diameters have worn
requiring
> replacement.  Maybe clips missing (if applicable).  Have fun!!
> Dave B.
> "Grosso, John" wrote:
>
> > Does anyone have any "truly innovative" methods for running leaders on
core
> > <.006" through older DES lines? We've played with tape, frames and
chases,
> > etc..Any help / guidance would truly be appreciated.
> >
> > Thanks,
> >
> > John S. Grosso
> > Vice President of Engineering & Technology
> > 4500 South Laburnum Avenue
> > Richmond, VA  23231
> > (804)226-5117 Office
> > (804)226-6025 Fax
> > [log in to unmask]
> >
> --
> Dave Brown
> Quality Manager
> RexCan Circuits
> [log in to unmask]
> 1-613-969-0009
> 161 Bridge St. E.
> Belleville Ont.
> K8N 5B6
>

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