Tom
CEM-1 is composed of paper, glass and epoxy resin.
The raw materials for CEM-3 and FR-4 are fiberglass and epoxy resin.
The main difference between them is the form of reinforcement.
The reinforcement for CEM-3 is a combination of woven glass and non-woven glass web.
On the other hand, FR-4 use all  woven glass. 
The overall performance of FR-4 is better than that of CEM-3, which is better than that of CEM-1. The cost is, you may guess, the complete reverse.
In terms of processibility, CEM-1 and CEM-3 are punchable.
One has to use a drill to process FR-4.
Of course, it is a general view so there may be exceptions for special grades.
We, Doosan Electro-materials, offer a variety of quality base materials including CEM-1, CEM-3, and FR-4 at competitive price.  
If you are interested, please call Mr. Kim who is our US office manager at 408-733-3553.

Minsu Lee
Associate Manager
R&D Dept.
Doosan Electro-materials.

----- Original Message ----- 
From: Tom Burek <[log in to unmask]>
To: <[log in to unmask]>
Sent: Wednesday, May 26, 1999 7:25 AM
Subject: [TN] Compare CEM-1, CEM-3 and FR4


> Can anyone tell me what CEM-3 is?  How does this differ from CEM-1 and FR4?  Is there a WEB site that list this information in one site?
> Thank You,
> 
> Tom Burek
> [log in to unmask]
> 
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