Ohhhhh no, you don't want me as a customer. I know ALL the unanswerable
questions to ask. Could be a major P.I.T.A. if I wanted to be....
Doug Pauls
Principal Materials and Process Engineer
Rockwell Collins
On Thu, Sep 22, 2016 at 3:20 PM, lduso - Diamond-MT.com <
[log in to unmask]> wrote:
> Rich, I couldn't agree more. And our batting average is about the same as
> yours, .500.
>
> We need more customers like Doug.
>
> Lloyd Duso
> Plant Manager
> Diamond-MT
> (814) 535-3505
> www.Diamond-mt.com
>
> On Thu, Sep 22, 2016 at 3:38 PM, Richard Kraszewski <
> [log in to unmask]> wrote:
>
> > Steve - We see the same issue when it gets really thin. We proceed as
> > follows:
> >
> > > State that fluorescence of a coating is an aide to inspection, not a
> > requirement.
> > > Coating will often thin -out at sharp edges. Laws of physics related
> > to surface tension & surface energy.
> > > If insufficient coating is suspected with UV & their naked eye
> > (spectacles are OK), operators can use up to 4X magnification and
> nature
> > white lighting to determine if coating is present based upon gloss.
> >
> > Common customer reply is that if coating is indeed present, then is must
> > be too thin to be in specification.
> > To which we reply back that the industry (IPC) understands this
> > phenomenon and a Qpanel hence can be used to monitor and control
> > thickness. If perfect coating uniformity is required , parylene should
> > be called out.
> >
> > We are successful in the above argument with customers perhaps 50% of
> the
> > time at best. Rest of the time we touch up. ;>(
> >
> > Rich Kraszewski / PLX
> >
> > -----Original Message-----
> > From: TechNet [mailto:[log in to unmask]] On Behalf Of Steve Gregory
> > Sent: Thursday, September 22, 2016 10:36 AM
> > To: [log in to unmask]
> > Subject: Re: [TN] Fwd: coating complaint
> >
> > Hi Guy,
> >
> > I got your photos posted, had to do a little repair with my web page
> > software after the last Windows update. Here are the images:
> >
> > http://stevezeva.homestead.com/coating_under_no_filter.jpg
> > http://stevezeva.homestead.com/customer_complaint-skips.jpg
> > http://stevezeva.homestead.com/coating_under_UV2.jpg
> > http://stevezeva.homestead.com/coating_under_UV2-1.jpg
> >
> > I see the same thing on component edges sometimes. It's like the UV
> tracer
> > in the coating thins out or separates out and under UV light it looks
> like
> > there's no coating. We've got stuff kicked from a customer for this
> > problem. If I can find the photos I'll post mine...
> >
> > Steve
> >
> > On Thu, Sep 22, 2016 at 7:56 AM, Guy Ramsey <[log in to unmask]>
> wrote:
> >
> > > I am in over my head. I have little to no experience with conformal
> > > coating. Can anyone with more experience comment?
> > > thanks,
> > > Guy
> > > ---------- Forwarded message ----------
> > > From: Guy Ramsey <[log in to unmask]>
> > > Date: Thu, Sep 22, 2016 at 9:51 AM
> > > Subject: Fwd: coating complaint
> > > To: [log in to unmask]
> > >
> > >
> > > I sent this message on to a friend who posts images for review by
> > > members of the IPC technet.
> > > We are looking for technical support and user experiences with this
> > > material.
> > > If we inspect at 5x-10x magnification we can observe the conditions
> > > that our customer is complaining about.
> > > But, our application process seems well controlled and the condition
> > > does not exist when the material is first dispensed. The material
> > > flows as it cures and becomes thin at the edges of the components.
> > > Thin enough so that is does not glow under UV light. In some instances
> > > components appear to have no coating (when viewed under UV). However
> > > under normal light it is easy to see the parts are coated.
> > > Is this normal behavior for the material? Can we expect normal
> > > performance from the the coating?
> > > Guy Ramsey
> > >
> > > ---------- Forwarded message ----------
> > > From: Guy Ramsey <[log in to unmask]>
> > > Date: Thu, Sep 22, 2016 at 9:41 AM
> > > Subject: coating complaint
> > > To: Steve Gregory <[log in to unmask]>
> > >
> > >
> > > Hi Steve,
> > > Can you post these images on your homestead page for the group please?
> > > The images are of acrylic coating Humiseal 1B31. We are applying a
> > > thinned mix using a dispenser through a fine needle (25AWG).
> > >
> > > Under room lighting we can see coating. Under UV light, at this
> > > magnification our customer is complaining about skips. I don't have
> > > enough experience with the material to know if this is normal or not.
> > > Notice how the resistor appears to have no coating under UV, but in
> > > normal light it is clearly coated.
> > > Also notice how the coating flows off of the components at the edges,
> > > leaving only a thin coating that may not glow under UV light.
> > > Are these normal attributes of this type coating.
> > >
> > > We do not see this with Urethane spray coatings.
> > >
> >
> > --
> >
> >
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