If I'm testing paste, then I want a guaranteed consistent surface for wetting. 
OSP has a relatively short shelf life. I'd think that bare copper of a certain 
polish and freshly lightly etched with citric acid (10%) would result in 
extremely high consistency. Since polishing and citric acid are easy to do, 
with cheap supplies and no real hazards, I'd just get some double clad etched 
with an array of the pad sizes IPC recommends and hold those in inventory, 
polishing and etching just before depositing the paste.

-----Original Message-----
From: TechNet [mailto:[log in to unmask]] On Behalf Of Drew meyer
Sent: Thursday, July 09, 2015 11:25 AM
To: [log in to unmask]
Subject: [TN] IPC-TM-650 2.4.45 Solder Paste-Wetting Test (Test Speciment)

Hi All,

I have been forced out from lurking in the shadows and listening to all the 
great knowledge.

I have been tasked with providing procurement information for the 
supplies/materials necessary to test some solder paste attributes at all of 
our sites.

Doing fine with stencils and glass microscope slides.  Not finding anything on 
the copper test coupon for wetting test.

Does anyone know of a source for the coupons ready made?  A plus would be 
ready made and OSP coated.

If ready made coupons are not available and you are testing solder paste for 
wetting, what do you use?

Drew Meyer