Matthew- As for where to get depanel tooling... Wand Tool does a great job.
-Chris
"Hybiske, Tom"
<Tom_Hybiske@BOS To: [log in to unmask]
E.COM> cc:
Sent by: Subject: [DC] How to break off IPC mouse bite
DesignerCouncil breakaways ??
<DesignerCouncil
@IPC.ORG>
06/26/02 11:22
AM
Please respond
to "(Designers
Council Forum)";
Please respond
to "Hybiske,
Tom"
Matthew,
For prototype runs and pilot runs we use a simple plastic fixture with a
milled groove the thickness of the board and the depth of the breakaway.
The
operator places the edge into the grooved fixture and levers the breakaway
off. It produces a very clean break and is also very efficient. For high
volume runs, we switch to shears.
Tom Hybiske
Bose Corporation
The Mountain
Framingham, MA 01701
> -----Original Message-----
> From: Matthew Lamkin [mailto:[log in to unmask]]
> Sent: Wednesday, June 26, 2002 10:54 AM
> To: [log in to unmask]
> Subject: Re: [DC] How to break of IPC mousebyte breakaways ??
>
>
> Hi there Chris, thanks for the reply,
>
> What is puzzling me is,
> These break off tabs, when manually broken off instead of getting a
> depanelling machine
> is the stress to the board, less than cutting an ordinary
> routed tab with
> cutters?
>
> Either way I can see the board stressed, and yes placement of
> ceramic caps
> is thought about, but does
> anyone know anywhere on the net where possible studies have
> been done on
> breakoff tab stresses etc?
>
> The reason I ask this is because we do not have (and I doubt
> if we would
> get) a depannelling machine that
> will break these tabs.
>
> We do relatively small volumes and use FR4 only.
>
> Most boards get scored where possible, but some have
> overhanging connectors
> that need tabs instead
> and I want to find out the very best method of supporting
> them in the panel.
>
> Also, is there any spec on the ordinary tab, how thick the
> centre should be
> etc?
>
> Actually, thinking about it, if we were to get a depannelling
> machine, what
> sort should we get?
>
> Thankyou - Matthew Lamkin.
>
> > -----Original Message-----
> > From: [log in to unmask] [SMTP:[log in to unmask]]
> > Sent: Tuesday, June 25, 2002 2:14 PM
> > To: [log in to unmask]
> > Subject: Re: [DC] How to break of IPC mousebyte breakaways ??
> >
> > Hi Matthew-
> > Never saw a reply to this so I'll give it a go. My advice
> is; if your
> > volumes are at all significant, don't do the by-hand or pliers thing
> > unless
> > you can lay the board out such that components, solder
> joints, and small
> > traces, are REALLY far away from the breakaways. Especially
> X7R caps. We
> > recently saw a problem where a cap more than 5MM from a breakaway
> > sometimes
> > cracked even though we were using special tooling for
> singulation. Turned
> > out that it was happening during ICT due to flexing. Easy
> to fix at the
> > ICT
> > process but points out the potential for problems associated with
> > breakaway
> > tabs.
> >
> > Low tech material like CEM-1 will often delaminate badly around the
> > breakaway if done by hand (or pliers).
> >
> > We use punch and/or shear tooling, routers, or Vscore, but
> all our stuff
> > is
> > pretty high volume.
> >
> > Lastly, I've never seen a plated hole used on a breakaway tab.
> > Regards,
> > -Chris
> >
>
---------------------------------------------------------------------------------
DesignerCouncil Mail List provided as a free service by IPC using LISTSERV
1.8d
To unsubscribe, send a message to [log in to unmask] with following text in
the BODY (NOT the subject field): SIGNOFF DesignerCouncil.
To set a vacation stop for delivery of DesignerCouncil send: SET
DesignerCouncil NOMAIL
Search previous postings at: www.ipc.org > On-Line Resources & Databases >
E-mail 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
---------------------------------------------------------------------------------
"This e-mail message is intended only for the use of the named
recipient(s).
The information contained therein may be confidential or privileged, and
its
disclosure or reproduction is strictly prohibited. If you are not the named
recipient, please return it immediately to its sender at the above address
and destroy it."
---------------------------------------------------------------------------------
DesignerCouncil Mail List provided as a free service by IPC using LISTSERV 1.8d
To unsubscribe, send a message to [log in to unmask] with following text in
the BODY (NOT the subject field): SIGNOFF DesignerCouncil.
To set a vacation stop for delivery of DesignerCouncil send: SET DesignerCouncil NOMAIL
Search previous postings at: www.ipc.org > On-Line Resources & Databases > E-mail 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
---------------------------------------------------------------------------------
|
