Dear Ed Shea,

I don't know about Invar or Cover in particular, but the
  Thermal Clad design guide
  http://www.bergquistcompany.com/thermal/tclad.htm
from Bergquist
has a lot of information on using their metal substrates as a PWB material.
(minimum hole sizes, clearance to edge of board, etc.).

Perhaps some of their tips on using metal as a PWB substrate will be useful.

Ed Shea <[log in to unmask]> on 2000-09-12 03:22:23 PM




Ed Shea <[log in to unmask]> on 2000-09-12 06:24:15 PM



I material is Kovar ASTM F15 not Invar.

 -----Original Message-----
From:   Ed Shea [mailto:[log in to unmask]]
Sent:   Tuesday, September 12, 2000 1:22 PM
To:     'TechNet'
Subject:        Machining Invar

We have an application where we are machining Invar. I understand that this
material has been used in PCBs and holes machined through the material.
Where can find a definitive machining guide for this material. Any
suggestions are appreciated in advance.

Edward G. Shea
909-981-1810
Test Connections Inc.
1146 West Ninth Street
Upland CA. 91786-5728
WWW.tciinfo.com

#

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