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
-----------------------------------------------------