Sorry I forgot to mention this in my previous 
submission.  The operator takes 2 slugs, not 1, twice per month.  One 
before cleaning  and one after.  We have SPC charts for both.  The 
"before" and "after" slugs are not that much different.  I can provide 
data for anyone interested.   Lou

.

On Mon, 5 Aug 1996 [log in to unmask] wrote:

> Joe, here are my comments about your HASL.
> 
> OUr guys clean the pot once per day.  The machine is only used on second 
> shift.
> 
> When we got a new Quicksilver machine about 2 years ago, it looks like Cu 
> contamination went down, according to our SPC chart.  The operators say 
> it is easier to clean the new machine than the old one.
> 
> We have an SPC chart to monitor Cu in the pot.  On the 5th and the 20th 
> of each month, the operator pulls a sample slug to be sent out for analysis.
> 
> Lou Hart
> 
> 
> .
> 
> On Mon, 5 Aug 1996, joef wrote:
> 
> >      Hello Technet,
> >      We are having difficulty maintaining our HASL pot below 0.25% Cu, even
> >      with 2x daily drossing.  The machine is an old vertical Electrovert 
> >      with less than easy access. 
> >      - Is this 0.25% more critical at assembly than at fab?
> >      - What is the practical USL for copper in HASL?
> >      - How often should metal contaminants be measured?
> >      - Should drossing be done at a constant frequency, or based on panel 
> >        loading?
> >      - Are there any studies out there correlating HASL quality with Cu 
> >        contamination level? 
> >      - Any special recommended procedures or tools?
> >      
> >      As always, we appreciate any input.
> >      Joe Felts
> >      PC World, Toronto
> > 
> > ***************************************************************************
> > * TechNet mail list is provided as a service by IPC using SmartList v3.05 *
> > ***************************************************************************
> > * To unsubscribe from this list at any time, send a message to:           *
> > * [log in to unmask] with <subject: unsubscribe> and no text.        *
> > ***************************************************************************
> > 
> 
> ***************************************************************************
> * TechNet mail list is provided as a service by IPC using SmartList v3.05 *
> ***************************************************************************
> * To unsubscribe from this list at any time, send a message to:           *
> * [log in to unmask] with <subject: unsubscribe> and no text.        *
> ***************************************************************************
> 

***************************************************************************
* TechNet mail list is provided as a service by IPC using SmartList v3.05 *
***************************************************************************
* To unsubscribe from this list at any time, send a message to:           *
* [log in to unmask] with <subject: unsubscribe> and no text.        *
***************************************************************************