Are your pads round?  I've seen bridging when the pads on the connector were rectangular or rounded rectangular.  They should be run with the length of the connector parallel to the wave.
Tom

 -----Original Message-----
From: [log in to unmask] [SMTP:MIME :[log in to unmask]]
Sent: Friday, August 13, 1999 3:31 PM
To: [log in to unmask]
Subject: Re: [TN] 50-mil pitch two row connectors

 << File: ENVELOPE.TXT >>
 --------------------------------------------------------------------------  --
Uday
   I saw a improvement when I changed from a No Clean flux 1.8 to 2 %
solids
to a Rosin based flux with 4 % solids, the number of bridging in paralel
conectors decreased, the lenght of the leads are important also. A good
DFM
practice is put this conector in perpendicular direction with the wave (
unfortunally due to many reasons this is not always followed ... ). Once
we
have to "live'' with 100% bridging due to bad design.
  I saw at soltec site one device that makes a kind of localized touch up
just after the lambda wave ( atached with the solder pot ) to remove
bridging from components, I don't know if works well but it is another
solution ... ( unfortunally my internet is down and I don't have the site
address )

Jorge Dourado de Santana
Maintenance / Process Engr
Microtec - Brazil



> To:   [log in to unmask]
> cc:    (bcc: Shean Dalton/ElectrovertUS/Cookson)
> Subject:  [TN] 50-mil pitch two row connectors
>
>
>
>
> Hello All
>
> We have 50-mil pitch two row TH connectors on some of our boards. The
> direction of flow in wave is parallel to the row of pins. This part
always
> bridges on the last pins as there is lot of drag at the end. We also
tried
> to add a thieving pad at the end of the last pin in the direction of
flow
> to help, but the test results didn't help much. (only 50% yield).
>
> Does anyone has experience with this case? Any help is appreciated
>
> Thanks
> Uday
>
> ##############################################################
> TechNet Mail List provided as a free service by IPC using LISTSERV 1.8c
> ##############################################################
> To subscribe/unsubscribe, send a message to [log in to unmask] with
> following
> text in
> the body:
> To subscribe:   SUBSCRIBE TECHNET <your full name>
> To unsubscribe:   SIGNOFF TECHNET
> ##############################################################
> Please visit IPC web site (http://www.ipc.org/html/forum.htm) for
> additional
> information.
> If you need assistance - contact Gayatri Sardeshpande at [log in to unmask] 

or
> 847-509-9700 ext.5365
> ##############################################################
>
>
>
>
>  << File: pic05092.pcx >>

##############################################################
TechNet Mail List provided as a free service by IPC using LISTSERV 1.8c
##############################################################
To subscribe/unsubscribe, send a message to [log in to unmask] with
following text in
the body:
To subscribe:   SUBSCRIBE TECHNET <your full name>
To unsubscribe:   SIGNOFF TECHNET
##############################################################
Please visit IPC web site (http://www.ipc.org/html/forum.htm) for
additional
information.
If you need assistance - contact Gayatri Sardeshpande at [log in to unmask] or
847-509-9700 ext.5365
##############################################################

##############################################################
TechNet Mail List provided as a free service by IPC using LISTSERV 1.8c
##############################################################
To subscribe/unsubscribe, send a message to [log in to unmask] with following text in
the body:
To subscribe:   SUBSCRIBE TECHNET <your full name>
To unsubscribe:   SIGNOFF TECHNET
##############################################################
Please visit IPC web site (http://www.ipc.org/html/forum.htm) for additional
information.
If you need assistance - contact Gayatri Sardeshpande at [log in to unmask] or
847-509-9700 ext.5365
##############################################################