TECHNET Archives

January 1998

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:
Wes Smith <[log in to unmask]>
Reply To:
TechNet E-Mail Forum.
Date:
Sat, 24 Jan 1998 18:19:18 +1100
Content-Type:
text/plain
Parts/Attachments:
text/plain (101 lines)
Hi Kandasamy,

Let me add a little to Jens comments. He is right about the difficulty in
piercing FR4. The 0.8mm  size is technically possible, but you need to use
a "step punch" ie a 3.2mm reducing to 0.8 for the last 20mm or so. This is
not really feasable in practice for the following reasons; the stripping
force needed for FR4 is very close to the piercing pressure. Most
mechanical presses cannot cope with "positive mechanical" stripping and
typically you will need something like a multi nitrogen gassed cylinder
stripper box fitted above the die set. It is very easy to pull the
bevelled heads off the piercing punches!

The punches should be HSS grade tool steel with annealed heads. I cant
remember the names of the manufacturers, but they were all German. The
initial "edge" goes off the tools very quickly with FR4, and then tends to
hold in a slightly "blunt" stage. Punch/die clearance is critical as is the
back relief in the die plate. Sorry but is was too long ago to remember the
exact detail, however the punch manufacturers will be able to provide that
data.

Lastly, the hole quality will be terrible and you will get a pile of fine
glass dust from the piercings. My advice - use a different material or drill!!

Good luck,

Wes Smith


At 08:49 24/01/98 +0800, you wrote:
>>Hello !
>
>Hello!
>
>>Can any one help us to provide the following informations regarding  FR4
>>laminates.
>
>Let's see.....
>
>>1. Is single sided 1.6mm thick  35 micron copper FR4 laminate available?
>>Who manufacture this type?
>
>Absolutely no problem. Even in India! Contact either 'PCS (in Pune)' or
>'Sandur Laminates' in Bangalore. I have both company details in the office
>(I'm home now). Low cost/grade FR4 35/0 is available in Delhi.
>
>>2. FR4 can be punch able? Both holes (diameter 0.8 mm to 5 mm) and outer
>>profile.
>
>FR4 is basically outline punchable. 0.80mm holes can NOT be punched. You
>need also a very good punch tool maintainance. FR4 is a glass material and
>glass is harder then steel.
>
>>3. If so, what type of tool is required?  Who is the supplier of such tool?
>
>Sorry, this one I donno.
>
>>With regards and advance thanks,
>>
>>Kandasamy Chandrabose
>
>Happy CHinese New Year!
>
>Jens Behrens
>
>The PCB Laminate FAQ:  http://www.felsweb.com/lam_faq.htm
>        ==========================================
>        Fels Ltd.       URL HTTP://www.felsweb.com
>        GPO Box 8721    Tel.: +(852) 2423-1812
>        Hong Kong       Fax.: +(852) 2423-1899
>                        [log in to unmask]
>        ==========================================
>
>################################################################
>TechNet E-Mail Forum 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://jefry.ipc.org/forum.htm) for additional
information.
>For the technical support contact Dmitriy Sklyar at [log in to unmask] or
847-509-9700 ext.311
>################################################################
>
>
>

################################################################
TechNet E-Mail Forum 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://jefry.ipc.org/forum.htm) for additional information.
For the technical support contact Dmitriy Sklyar at [log in to unmask] or 847-509-9700 ext.311
################################################################


ATOM RSS1 RSS2