Actually, we are doing manual spraying while my contractors used automated machines. Both coating processes are able to achieve the thickness required (IPC 610/ CC-830)but with matte surface, (we cut the coating layer to measure in highpower scope). Hence, I was concerned that there is a clause that indicates matte surface is a defect. Thank you all.
________________________________
From: TechNet on behalf of Douglas Pauls
Sent: Thu 8/27/2009 7:58 PM
To: [log in to unmask]
Subject: Re: [TN] Manual spraying, further qs
Well, to add to what Graham has said, gloss and matte may also have to do
with how a coating is applied and dried. We have instances of a coating
that is normally glossy when spray applied. If you happen to do touch up
spray before the first application of coating is dry, then the surface
appears matte. In all the testing that I have done on the phenomena, I
have come to the conclusion that this is a purely cosmetic issue and has
nothing to do with functional performance.
Doug Pauls
Graham Naisbitt <[log in to unmask]>
Sent by: TechNet <[log in to unmask]>
08/27/2009 04:19 AM
Please respond to
TechNet E-Mail Forum <[log in to unmask]>; Please respond to
Graham Naisbitt <[log in to unmask]>
To
[log in to unmask]
cc
Subject
Re: [TN] Manual spraying, further qs
Tan
There is no actual requirement that the coating should have a glossy
finish - nor does it say that a matt finish is not acceptable - See
IPC-A610D 10.5.2
However, If you take virtually any conformal coating and apply it to a
clean, dry, bare copper pad, it will be glossy. Now if you apply it to
a bare board surface, with or without a resist, and it is matt, then
that would suggest it has been absorbed into the laminate, in part or
in full.
In this instance the coating would not have the required thickness as
defined in IPC-CC-830.
Does that help?
Regards
Graham Naisbitt
Email: [log in to unmask]
Phone: +44 (0)12 5252 1500
Web: www.gen3systems.com
On 27 Aug 2009, at 03:41, Tan Geok Ang wrote:
> Conformal coating with Matt surface is not acceptable?
> (Any specification/standard indicated this?)
> Thanks!
>
>
>
> ----- Original Message -----
> From: TechNet <[log in to unmask]>
> To: [log in to unmask] <[log in to unmask]>
> Sent: Mon Aug 24 17:38:49 2009
> Subject: Re: [TN] Manual spraying, further qs
>
> Thanks Ken,
> are there any stds that demand a perfect surface, e.g. any IPC
> standards.
> And what use to cause outgassing issues? I have several PWB courses
> behind,
> but many, many years ago. Can dig in my piles, but a faster answer
> from
> TN
> seems a bit more comfortable.
> /Inge
>
>
> ----- Original Message -----
> From: "Ken Bloomquist" <[log in to unmask]>
> To: <[log in to unmask]>
> Sent: Monday, August 24, 2009 11:20 PM
> Subject: Re: [TN] Manual spraying, further qs
>
>
>> The bad board had beans for lunch, "bad out gassing problem"! :-)
>>
>> KennyB
>>
>> -----Original Message-----
>> From: Inge [mailto:[log in to unmask]]
>> Sent: Monday, August 24, 2009 1:50 PM
>> To: [log in to unmask]
>> Subject: Re: [TN] Manual spraying, further qs
>>
>> This very day, I couldn't stay aside but had to do something to help
> the
>> production guys. So, I took a fresh, naked and qualified board from
>> another
>> source and did this:
>> Put one of our problem boards beside the reference board, both on
> bottom
>> of
>> a larg well box, i.e. no fans blowing, nor any evacuation. Sprayed
> both
>> simultaneosly. Inspected them after one hour at room temp. The
> reference
>> board was absolutely perfect, while the other was matte! Had a look
>> in
> a
>> microscope. The bad guy had thousands of microscopic inclusions and
> even
>> superficial voids, the reference was perfect. Noticed that the bad
> boards
>> have a much coarser (looks like the net pattern after screen
>> printing)green
>> sheet (solder mask) and numerous voids already before spraying. What
> is
>> your
>>
>> opinion?
>> /Inge
>>
>>
>> ---------------------------------------------------
>> Technet Mail List provided as a service by IPC using LISTSERV 15.0
>> To unsubscribe, send a message to [log in to unmask] with following
>> text
> in
>> the BODY (NOT the subject field): SIGNOFF Technet
>> To temporarily halt or (re-start) delivery of Technet send e-mail to
>> [log in to unmask]: SET Technet NOMAIL or (MAIL)
>> To receive ONE mailing per day of all the posts: send e-mail to
>> [log in to unmask]: SET Technet Digest
>> Search the archives of previous posts at:
> http://listserv.ipc.org/archives
>> Please visit IPC web site
> http://www.ipc.org/contentpage.asp?Pageid=4.3.16
>> for additional information, or contact Keach Sasamori at
> [log in to unmask] or
>> 847-615-7100 ext.2815
>> -----------------------------------------------------
>
> ---------------------------------------------------
> Technet Mail List provided as a service by IPC using LISTSERV 15.0
> To unsubscribe, send a message to [log in to unmask] with following text
> in
> the BODY (NOT the subject field): SIGNOFF Technet
> To temporarily halt or (re-start) delivery of Technet send e-mail to
> [log in to unmask]: SET Technet NOMAIL or (MAIL)
> To receive ONE mailing per day of all the posts: send e-mail to
> [log in to unmask]: SET Technet Digest
> Search the archives of previous posts at:
> http://listserv.ipc.org/archives
> Please visit IPC web site
> http://www.ipc.org/contentpage.asp?Pageid=4.3.16 for additional
> information, or contact Keach Sasamori at [log in to unmask] or
> 847-615-7100
> ext.2815
> -----------------------------------------------------
>
> ---------------------------------------------------------------------
> This transmission (including any attachments) may contain confidential
> information, privileged material (including material protected by the
> solicitor-client or other applicable privileges), or constitute
> non-public information. Any use of this information by anyone other
> than
> the intended recipient is prohibited. If you have received this
> transmission in error, please immediately reply to the sender and
> delete
> this information from your system. Use, dissemination, distribution,
> or
> reproduction of this transmission by unintended recipients is not
> authorized and may be unlawful.
>
> ---------------------------------------------------
> Technet Mail List provided as a service by IPC using LISTSERV 15.0
> To unsubscribe, send a message to [log in to unmask] with following text
> in
> the BODY (NOT the subject field): SIGNOFF Technet
> To temporarily halt or (re-start) delivery of Technet send e-mail to
> [log in to unmask]: SET Technet NOMAIL or (MAIL)
> To receive ONE mailing per day of all the posts: send e-mail to
> [log in to unmask]: SET Technet Digest
> Search the archives of previous posts at:
> http://listserv.ipc.org/archives
> Please visit IPC web site
> http://www.ipc.org/contentpage.asp?Pageid=4.3.16 for additional
> information, or contact Keach Sasamori at [log in to unmask] or
> 847-615-7100
> ext.2815
> -----------------------------------------------------
>
> ---------------------------------------------------
> Technet Mail List provided as a service by IPC using LISTSERV 15.0
> To unsubscribe, send a message to [log in to unmask] with following
> text in
> the BODY (NOT the subject field): SIGNOFF Technet
> To temporarily halt or (re-start) delivery of Technet send e-mail to
[log in to unmask]
> : SET Technet NOMAIL or (MAIL)
> To receive ONE mailing per day of all the posts: send e-mail to
[log in to unmask]
> : SET Technet Digest
> Search the archives of previous posts at:
http://listserv.ipc.org/archives
> Please visit IPC web site
http://www.ipc.org/contentpage.asp?Pageid=4.3.16
> for additional information, or contact Keach Sasamori at [log in to unmask]
> or 847-615-7100 ext.2815
> -----------------------------------------------------
---------------------------------------------------
Technet Mail List provided as a service by IPC using LISTSERV 15.0
To unsubscribe, send a message to [log in to unmask] with following text in
the BODY (NOT the subject field): SIGNOFF Technet
To temporarily halt or (re-start) delivery of Technet send e-mail to
[log in to unmask]: SET Technet NOMAIL or (MAIL)
To receive ONE mailing per day of all the posts: send e-mail to
[log in to unmask]: SET Technet Digest
Search the archives of previous posts at: http://listserv.ipc.org/archives
Please visit IPC web site http://www.ipc.org/contentpage.asp?Pageid=4.3.16
for additional information, or contact Keach Sasamori at [log in to unmask] or
847-615-7100 ext.2815
-----------------------------------------------------
---------------------------------------------------
Technet Mail List provided as a service by IPC using LISTSERV 15.0
To unsubscribe, send a message to [log in to unmask] with following text in
the BODY (NOT the subject field): SIGNOFF Technet
To temporarily halt or (re-start) delivery of Technet send e-mail to [log in to unmask]: SET Technet NOMAIL or (MAIL)
To receive ONE mailing per day of all the posts: send e-mail to [log in to unmask]: SET Technet Digest
Search the archives of previous posts at: http://listserv.ipc.org/archives
Please visit IPC web site http://www.ipc.org/contentpage.asp?Pageid=4.3.16 for additional information, or contact Keach Sasamori at [log in to unmask] or 847-615-7100 ext.2815
-----------------------------------------------------
---------------------------------------------------
Technet Mail List provided as a service by IPC using LISTSERV 15.0
To unsubscribe, send a message to [log in to unmask] with following text in
the BODY (NOT the subject field): SIGNOFF Technet
To temporarily halt or (re-start) delivery of Technet send e-mail to [log in to unmask]: SET Technet NOMAIL or (MAIL)
To receive ONE mailing per day of all the posts: send e-mail to [log in to unmask]: SET Technet Digest
Search the archives of previous posts at: http://listserv.ipc.org/archives
Please visit IPC web site http://www.ipc.org/contentpage.asp?Pageid=4.3.16 for additional information, or contact Keach Sasamori at [log in to unmask] or 847-615-7100 ext.2815
-----------------------------------------------------
|
