Phil, Fair enough. Can you poll the possible CMs with respect to their capabilities / limitations? Get an idea of how familiar they are with using partial wave fixtures and/or do they have selective solder machines? A good CM will work with you on the design - it's in their best interests to ensure it can be built by them... if the design is going to be a challenge you may want to / need to pre-select who will build it based on capabilities (AKA going with "best value" instead of "best price"...)?? good luck! regards, - Graham -----Original Message----- From: Phil Nutting [mailto:[log in to unmask]] Sent: Thursday, March 13, 2008 12:35 PM To: Collins, Graham (FN) @ ESI; TechNet E-Mail Forum Subject: RE: [TN] SMT layout Graham, OK. I forgot to add that these will be built by a CM. Depending on which CM it goes to may vary how the boards are soldered. Phil -----Original Message----- From: [log in to unmask] [mailto:[log in to unmask]] Sent: Thursday, March 13, 2008 11:30 AM To: TechNet E-Mail Forum; Phil Nutting Subject: RE: [TN] SMT layout Hi Phil I don't do layout, but our design guys can attest that I spend _lots_ of time bugging them about it. Enough so that they've adopted the "get him to review it first" attitude, which I really appreciate. With respect to your issue (10 lbs in 5 lb bag), we'd look at doing partial wave (using a selective soldering pallet for the wave solder operation). If you can do that, the restriction on the bottom side SMT parts are: - max height ~ .200" - need a margin around all through-hole parts to allow for the vertical wall on the pallet. - the through-hole parts can't block all access to SMT parts. Of course, if you've got a selective soldering machine then you've got even more flexibility, almost anything on the bottom should be OK. Hope that helps a bit. regards, - Graham -----Original Message----- From: TechNet [mailto:[log in to unmask]] On Behalf Of Phil Nutting Sent: Thursday, March 13, 2008 12:19 PM To: [log in to unmask] Subject: [TN] SMT layout Hi folks, Disclaimer: I'm a neophyte at SMT board layout. That being said, we have a board that equates to 10 pounds in a 5 pound bag. Is there a recommended layout with reference to which components should be on the component side versus the solder side? I assume it is partially affected by the method of processing, reflow or wave for solder side. Put passive parts on the solder side and the active parts on the component side? Thanks in advance, Phil Note: All the information contained in this e-mail and its attachments is proprietary to Kaiser Systems, Inc. and it may not be reproduced without the prior written permission of sender. If you have received this email in error, please immediately return it to sender and delete the copy you received. --------------------------------------------------- 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 ----------------------------------------------------- Note: All the information contained in this e-mail and its attachments is proprietary to Kaiser Systems, Inc. and it may not be reproduced without the prior written permission of sender. If you have received this email in error, please immediately return it to sender and delete the copy you received. --------------------------------------------------- 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 -----------------------------------------------------