Same with this one.
        Ramon

> -----Original Message-----
> From: Dehoyos, Ramon
> Sent: Friday, August 08, 2003 12:49 PM
> To:   'TechNet E-Mail Forum.'; [log in to unmask]
> Subject:      RE: [TN] Wave Solder Preheat
>
>       Al:
>       The dwell time will be more than 7 seconds. Depending on the type of
> machine, it might be more than 10 seconds at that slow speed.
>       Ramon
>
> -----Original Message-----
> From: [log in to unmask] [SMTP:[log in to unmask]]
> Sent: Friday, August 08, 2003 8:47 AM
> To:   [log in to unmask]
> Subject:      [TN] Wave Solder Preheat
>
> Hello Technetters,
>
> I have a family of boards that to achieve 100% hole fill (I'm building to
> IPC-A-610C class 2 - yeah, I know 100% isn't required), I need to preheat
> the topside of the board to approximately 310F at about 1.75 ft/min (maybe
> a 6-7 second dwell).  I usually follow the 180-220F rule-of-thumb, so I'm
> asking: What are the potential or real problems?  Also, the flux is OA.
>
> The family of boards are .050-.070" made out of either FR4, GE TEK, or
> NELCO 4000-13.  They are also waved in a selective soldering pallet with
> an
> aluminum plate on the topside over 90% of the components to hold them in
> place per a design specification.
>
> Will I damage the board or components (with immediate noticeable failures
> or latent field failures)?  Or is the 180-220F guideline more from the old
> WS6536/Mil-Std-2000 days and todays fluxes, boards, and components can
> handle the temperatures?
>
> Thanks in advance for the help,
>
> Al Kreplick
> Sr. Mfg. Eng.
> Teradyne, Inc.
> 500 Riverpark Drive
> Mail Stop NR500 1-1
> North Reading, MA 01864
> Tel: 978-370-1726
> Fax: 734-661-5352
> Pager: 888-561-6485
>
> ---------------------------------------------------
> 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
-----------------------------------------------------