TECHNET Archives

January 2009

TechNet@IPC.ORG

Options: Use Monospaced Font
Show Text Part by Default
Show All Mail Headers

Message: [<< First] [< Prev] [Next >] [Last >>]
Topic: [<< First] [< Prev] [Next >] [Last >>]
Author: [<< First] [< Prev] [Next >] [Last >>]

Print Reply
Subject:
From:
"Braddock, Iain (UK)" <[log in to unmask]>
Reply To:
TechNet E-Mail Forum <[log in to unmask]>, Braddock, Iain (UK)
Date:
Thu, 29 Jan 2009 11:22:42 -0000
Content-Type:
text/plain
Parts/Attachments:
text/plain (189 lines)
Larry,

I agree with most of your points, however, the system we procured works
on a different principal than most of its competitors in that it's the
solder pot that moves. This allows a top heater to be sited over the pot
allowing constant preheating of the board whilst performing a sequential
soldering operation; this I found was crucial to soldering thermally
challenging boards.

	Iain.

-----Original Message-----
From: TechNet [mailto:[log in to unmask]] On Behalf Of Larry Dzaugis
Sent: 29 January 2009 05:40
To: [log in to unmask]
Subject: Re: [TN] SELECTIVE SOLDERING TEMPERATURES

Compared to wave soldering a much higher temperture is required.
There is much less solder mass touching the solder joint to transfer
heat.
There is less dross as well.

Smaller variations arise from the variability of PCA and components.
Selective doing point to point soldering will be higher than a dip into
a multiwave selective solder.
The actual temp of the solder can be cooler than the pot settings when
measured at the top of the solder nozzle. There is less delta with a
12mm nozzle compared to a 4mm nozzle. The design of the nozzle and how
the solder flows over the edge varies..

Frequently the optimum flux will be different than that used by a wave.
The preheaters are much less robust compared to the 6 foot with
convection available on many wave solder machines. Most selective
preheaters are not convection, which makes VOC free fluxes more
challenging.
Most of the preheat is lost on point to point soldering.
Just ran a panel that took 5:55 minutes to solder. Not much preheat left
for the 2 and 3rd  PCA in the array.

The 285 to 290C mentioned above would be a place to start.
Profile your own product and process for actual numbers.






On Wed, Jan 28, 2009 at 10:51 AM, Stadem, Richard D. <
[log in to unmask]> wrote:

> 290C. Per Pillarhouse recommendations, supported by qualification 
> results. Preheat temp is critical.
>
> -----Original Message-----
> From: TechNet [mailto:[log in to unmask]] On Behalf Of Braddock, Iain 
> (UK)
> Sent: Wednesday, January 28, 2009 10:46 AM
> To: [log in to unmask]
>  Subject: Re: [TN] SELECTIVE SOLDERING TEMPERATURES
>
> 285C!
>
> -----Original Message-----
> From: TechNet [mailto:[log in to unmask]] On Behalf Of Lee Whiteman
> Sent: 28 January 2009 16:32
> To: [log in to unmask]
> Subject: [TN] SELECTIVE SOLDERING TEMPERATURES
>
>               *** WARNING ***
>
> This mail has originated outside your organization, either from an 
> external partner or the Global Internet.
>     Keep this in mind if you answer this message.
>
> What temperatures do folks operate their selective solder units with 
> SnPb solder?
>
> In my prior life, I ran my wave soldering machine with SnPb at ~ 500F 
> / 260C with good results. Guys in the shop are running considerably 
> higher (~ 584F / 306C) citing board density concerns. My response 
> would be to judiciously increase the thermal profile / preheat 
> temperatures but not the solder pot temperature. The higher solder pot

> temperature results in much more dross and tin oxides.
>
> Just curious...
>
> Lee Whiteman, PMP
> Senior Member Engineering Staff
> L-3 Communications East
> Telephone: (856) 338-3508
> FAX: (856) 338-2906
> E-Mail: [log in to unmask]
>
> ---------------------------------------------------
> 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 email and any attachments are confidential to the intended 
> recipient and may also be privileged. If you are not the intended 
> recipient please delete it from your system and notify the sender. You

> should not copy it or use it for any purpose nor disclose or 
> distribute its contents to any other person.
>
> MBDA UK Limited, a company registered in England and Wales, 
> registration number 3144919 whose registered office is at Six Hills 
> Way, Stevenage, Hertfordshire, SG1 2DA, England.
> ********************************************************************
>
> ______________________________________________________________________
> This email has been scanned by the MessageLabs Email Security System.
> For more information please visit http://www.messagelabs.com/email 
> ______________________________________________________________________
>
> ---------------------------------------------------
> 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=4.3.16for 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 email has been scanned by the MessageLabs Email Security System.
For more information please visit http://www.messagelabs.com/email 
______________________________________________________________________

---------------------------------------------------
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
-----------------------------------------------------

ATOM RSS1 RSS2