Brian,
I appreciate there are other factors involved in assessing the compatibility
of various production chemistries and that good SIR does not necessarily
mean good compatibility.
However, I was only addressing Bev's paragraph, to try and point out that
there was a standard being developed for exactly this process of
SIR/electromigration characterisation.
"Some companies also have internal tests where they mix their wave solder
flux, paste flux, cored wire flux and chip adhesive and test that dog's
breakfast using SIR and electromigration. Again they are obviously only
testing the most likely combinations, not every combination possible from
their AVL (approved vendor list).
But I know of no standard that specifically deals with this issue"
I hope I didn't upset the apple cart too much, and apologise if the comment
was misleading in any way.
Best Regards,
Phil
-----Original Message-----
From: TechNet [mailto:[log in to unmask]] On Behalf Of Brian Ellis
Sent: 13 March 2003 14:29
To: [log in to unmask]
Subject: Re: [TN] Mixing fluxes - documentation vacuum
Phil
SIR is most certainly not the be all and end all of flux compatibility.
Whereas SIR may be used as a negative test (poor SIR = poor
compatibility, good SIR does NOT necessarily mean good compatibility),
other tests are also necessary.
Brian
Phil Kinner wrote:
> Bev,
>
> IEC 61189-5 is a draft spec, currently at an advanced stage (final draft I
> believe) which deals with process characterization using SIR, to ensure
that
> all the chemistries used in the assembly of a PCA are compatible and that
> the assembly process is good from an SIR point of view.
>
> If you'd like a copy, I'm sure I could sort you out with something.
>
> Best Regards,
>
> Phil Kinner
> Concoat Ltd
>
>
> -----Original Message-----
> From: TechNet [mailto:[log in to unmask]] On Behalf Of Bev Christian
> Sent: 13 March 2003 13:26
> To: [log in to unmask]
> Subject: Re: [TN] Mixing fluxes - documentation vacuum
>
> If the fluxing materials come from different suppliers you will never get
> them to officially put in print that they are compatible with each other.
I
> know if I were them, I never would. Think of all the combinations they
> would have to test!
>
> Now if you are lucky, on a good day you might get some of the bigger
> companies to say their own wave flux and own solder paste are compatible.
>
> I know for a fact that some fluxes/solder pastes produced five years ago
> were not compatible with certain solder masks. But things have got better
> in terms of both the flux and solder mask chemistries, so this is much
more
> rare.
>
> Some companies also have internal tests where they mix their wave solder
> flux, paste flux, cored wire flux and chip adhesive and test that dog's
> breakfast using SIR and electromigration. Again they are obviously only
> testing the most likely combinations, not every combination possible from
> their AVL (approved vendor list).
>
> But I know of no standard that specifically deals with this issue.
>
> regards,
> Bev Christian
> Research in Motion
>
> -----Original Message-----
> From: Cagle, James [mailto:[log in to unmask]]
> Sent: March 12, 2003 1:52 PM
> To: [log in to unmask]
> Subject: Re: [TN] Mixing fluxes - documentation vacuum
>
>
> In J-STD-001,it says the fluxes must be compatible. Have your CM show you
> data from both Paste/Flux manufacture that their products are OK to be
used
> with each other. >
>
>> James Cagle
>>Tyco Printed Circuit Group-Hayward Division
>>
>> email: [log in to unmask]
>>
>
>
>
> -----Original Message-----
> From: Dave Hillman [mailto:[log in to unmask]]
> Sent: Tuesday, March 11, 2003 7:45 AM
> To: [log in to unmask]
> Subject: Re: [TN] Mixing fluxes - documentation vacuum
>
>
> Hi John! Take a look in the IPC-HDBK-001, section 7.2.1 flux application,
> last paragraph. There is a cautionary statement (similar to the JSTD-001
> statement Guy referenced) about the mixing of fluxes and the potential
> hazard of added liquid flux as a soldering aid.
>
> Dave Hillman
> Rockwell Collins
> [log in to unmask]
>
>
>
>
> "Vivari, John"
> <[log in to unmask] To: [log in to unmask]
> COM> cc:
> Sent by: TechNet Subject: [TN] Mixing
fluxes
> - documentation vacuum
> <[log in to unmask]>
>
>
> 03/11/2003 08:10
> AM
> Please respond to
> "TechNet E-Mail
> Forum."; Please
> respond to
> "Vivari, John"
>
>
>
>
>
>
> Dear TechNetters,
>
> A customer of ours came to us with a request for a reference to an IPC
> document or other industry standard that explicitly states the hazards of
> mixing flux types on an assembly. He asked for this because his contract
> manufacturer built a set of boards using a No-clean solder paste and
> reworked some BGAs with a water soluble solder paste. The contract
> manufacture states that he cannot find a standard "anywhere" that says the
> flux types should not be mixed or that there will be any long term
> reliability issues. I know this seems naive but that is their position.
>
> We have searched our library of specifications, books, and industry
> periodicals and have come up empty except for vague statements about
having
> to clean between soldering operations for certain classes of product
> without
> explaining why and a reference in Ning-Cheng Lee's new book cautioning
> against combining incompatible fluxes between reflow and wave soldering.
> We
> are well versed in the hazards of mixing our own fluxes (never mind
others)
> but have never been asked to provide "industry standard documentation"
> before (as opposed to a letter of explanation).
>
> Can anyone point to a reference that we have missed?
>
> Hopefully yours,
>
> John Vivari
> Technical Service Engineer
> EFD Inc.
> [log in to unmask]
> www.efdsolder.com
> Ph: 401-333-3800
> Fx: 401-333-4954
>
> ---------------------------------------------------
> Technet Mail List provided as a free service by IPC using LISTSERV 1.8e
> 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/html/forum.htm for additional
> information, or contact Keach Sasamori at [log in to unmask] or 847-509-9700
> ext.5315
> -----------------------------------------------------
>
> ---------------------------------------------------
> Technet Mail List provided as a free service by IPC using LISTSERV 1.8e
> 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/html/forum.htm for additional
> information, or contact Keach Sasamori at [log in to unmask] or 847-509-9700
> ext.5315
> -----------------------------------------------------
>
> ---------------------------------------------------
> Technet Mail List provided as a free service by IPC using LISTSERV 1.8e
> 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/html/forum.htm for additional
> information, or contact Keach Sasamori at [log in to unmask] or 847-509-9700
> ext.5315
> -----------------------------------------------------
>
> ---------------------------------------------------
> Technet Mail List provided as a free service by IPC using LISTSERV 1.8e
> 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/html/forum.htm for additional
> information, or contact Keach Sasamori at [log in to unmask] or 847-509-9700
> ext.5315
> -----------------------------------------------------
>
> ---------------------------------------------------
> Technet Mail List provided as a free service by IPC using LISTSERV 1.8e
> 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/html/forum.htm for additional
> information, or contact Keach Sasamori at [log in to unmask] or 847-509-9700
ext.5315
> -----------------------------------------------------
>
>
>
>
>
---------------------------------------------------
Technet Mail List provided as a free service by IPC using LISTSERV 1.8e
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/html/forum.htm for additional
information, or contact Keach Sasamori at [log in to unmask] or 847-509-9700
ext.5315
-----------------------------------------------------
---------------------------------------------------
Technet Mail List provided as a free service by IPC using LISTSERV 1.8e
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/html/forum.htm for additional
information, or contact Keach Sasamori at [log in to unmask] or 847-509-9700 ext.5315
-----------------------------------------------------
|
