If you are using vias for heat transfer, you don't use thermal relief "spokes". (via pads are flooded into the copper pours) Jack . On Tue, 5 Jan 2010 10:31:02 -0500, Tontis, Theodore <[log in to unmask]> wrote: >Bill, > >Do you know if that calculator can adjust the thermo relief used to attach the via to a plane? I would be interested to see if changing the number and or size of the spokes would have a greater impact then having it filled in with solder? I would also be interested to see how much more thermally conductive a direct connect via vs. a thermo relief via can be. > >I have often wondered if the formula for thermo reliefs could be tweaked to provide the best of both worlds. > >Ted T. --------------------------------------------------- Technet Mail List provided as a service by IPC using LISTSERV 15.0 To unsubscribe, send a message to [log in to unmask] with following text in the BODY (NOT the subject field): SIGNOFF Technet To temporarily halt or (re-start) delivery of Technet send e-mail to [log in to unmask]: SET Technet NOMAIL or (MAIL) To receive ONE mailing per day of all the posts: send e-mail to [log in to unmask]: SET Technet Digest Search the archives of previous posts at: http://listserv.ipc.org/archives Please visit IPC web site http://www.ipc.org/contentpage.asp?Pageid=4.3.16 for additional information, or contact Keach Sasamori at [log in to unmask] or 847-615-7100 ext.2815 -----------------------------------------------------