One of the worst cases is in my opinion if the leads are of Alloy 42 or Kovar.
Crystals have leads of this material, as the manufacturer is interested in the smallest
difference in thermal ex. coeff. between glass and leads. I am sure that you know the
other consequences on the solder joint.
Another bad experience we had was when the bending caused cracks in the heel of the
formed lead of a connector , preventing the solder wetting on the heel .
Gaby

[log in to unmask] wrote:

> Lately I have been seeing failure analysis that indicates the failures
> were caused by trying to take a through hole component and bending
> the leads up and around or under the component body to make it
> a surface mount component.  In one case a crystal seal was broken
> and another the bends were just too "springy".
>
> Is there a set of suggestions as to how and when and IF this can be
> done to a through hole component?
>
> Susan Mansilla
> Technical Director
> Robisan Lab
>
> ##############################################################
> 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
##############################################################