Tom,

I use 0.015 on reflow.


Look at your grid.  Figure out where you want your via in relation to the lands.
Adjust the soldermask by overlapping the mask on the via to allow 0.015 exposed via to land.
Then set the via to pad clearance to whatever the copper clearance ends up to be.
Not violating bareboard DFM rules of course.
This will allow the via to be that much closer to the land.

---------------------------
John Laur
Rockwell Automation
Allen-Bradley Co Inc.                 
1201 South Second Street
Milwaukee, WI 53204
+1 414 382 2162 (fax)
+1 414 382 2393 (phone)

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		I am looking for any information concerning the minimum distance between
		a via to smt land (1206, 0805, and 0603). Currently we are using a 
	        .015 hole / .030 pad non-tented via. Is anyone out there burying the
		via in the center of the land? The wave side is not as much of a concern
	        as the reflow side. We are planning to run some test boards with several
		configurations. I would appreciate any feed back.
	
	
		Tom Vaillancourt
		Philips Consumer Electronics Co.
		615-521-3482
		Internet: [log in to unmask]