Ian,

Effectively, this kind of PCB are only used with
stable mechanical support (generally machined RF enclosures).
The "optional" breakable part of the PCB is considered like
a "totally" independent print with it's own mechanical fixation;
holes have sufficient tolerances in diameter to avoid
constraints. The only  precautions are taken during
components placement, soldering, initial test and transport,
In fact, it is as if we had 2 well fixed independant PCB
connected by some resistors.

Have a nice day,

Rudolf

----- Original Message -----
From: "Ian Wilson" <[EMAIL PROTECTED]>
To: "Protel EDA Forum" <[EMAIL PROTECTED]>
Sent: Wednesday, June 26, 2002 10:19 AM
Subject: Re: [PEDA] PCB breakoffs


> On 08:15 AM 26/06/2002 +0200, Rudolf Schaffer said:
> >Hello,
> >
> >In this case, we use v-grooving and SMD 0 ohm
> >with a convenient foot-print, for each
> >net (if not too many!) crossing over.
> >
> >We naturally have 2 "plans d'implantation" depending
> >upon the cutted/non cutted PCB part.
> >
> >Have a nice day,
> >
> >Rudolf Schaffer
>
> Rudolf,
>
> I am intrigued by this.
>
> How do you prevent flexing of the board from transferring stress onto the
> small surface mount resistors and cracking them or the solder joints?  A
> V-groove flexes at quite a sharp angle. (by design). I guess some thing
> like this would never be used in anything but very stable controlled
> environments.
>
> Actually now that I think about it this stress is a problem also for the
> routed/break-off tab implementation but maybe the copper is a little more
> malleable than those ceramic resistors.
>
> Ian Wilson
>
>
>
> ************************************************************************
> * Tracking #: 533015C9F8865B4F90F49353E155EDDCD7B65F11
> *
> ************************************************************************

* * * * * * * * * * * * * * * * * * * * * * * * * * * * * *
* To post a message: mailto:[EMAIL PROTECTED]
*
* To leave this list visit:
* http://www.techservinc.com/protelusers/leave.html
*
* Contact the list manager:
* mailto:[EMAIL PROTECTED]
*
* Forum Guidelines Rules:
* http://www.techservinc.com/protelusers/forumrules.html
*
* Browse or Search previous postings:
* http://www.mail-archive.com/proteledaforum@techservinc.com
* * * * * * * * * * * * * * * * * * * * * * * * * * * * * *

Reply via email to