X-Authentication-Warning: delorie.com: mail set sender to geda-user-bounces using -f X-Recipient: geda-user AT delorie DOT com X-Envelope-From: paubert AT iram DOT es Date: Tue, 3 Feb 2015 08:22:16 +0100 From: Gabriel Paubert To: geda-user AT delorie DOT com Subject: Re: [geda-user] Footprint Generator Message-ID: <20150203072216.GA28920@visitor2.iram.es> References: <1345A71A-1F70-4FCD-B738-883EA3C833E5 AT sbcglobal DOT net> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1345A71A-1F70-4FCD-B738-883EA3C833E5@sbcglobal.net> User-Agent: Mutt/1.5.21 (2010-09-15) X-Spamina-Bogosity: Unsure X-Spamina-Spam-Score: -1.0 (-) X-Spamina-Spam-Report: Content analysis details: (-1.0 points) pts rule name description ---- ---------------------- -------------------------------------------------- -1.0 ALL_TRUSTED Passed through trusted hosts only via SMTP 0.0 URIBL_BLOCKED ADMINISTRATOR NOTICE: The query to URIBL was blocked. See http://wiki.apache.org/spamassassin/DnsBlocklists#dnsbl-block for more information. [URIs: gedasymbols.org] -0.0 BAYES_40 BODY: Bayes spam probability is 20 to 40% [score: 0.2480] Reply-To: geda-user AT delorie DOT com Errors-To: nobody AT delorie DOT com X-Mailing-List: geda-user AT delorie DOT com X-Unsubscribes-To: listserv AT delorie DOT com Precedence: bulk On Mon, Feb 02, 2015 at 06:42:12PM -0800, Edward Hennessy wrote: > > > On Feb 1, 2015, at 8:28 PM, Kai-Martin Knaak wrote: > > > > Edward Hennessy wrote: > > > >> I've created a GUI footprint generator for PCB. > > > > Yet another suggestion: > > > > Add the ability to make thru hole pins oblate on the solder side. This > > facilitates manual soldering and still allows for a signal or two to > > go between two pins. > > > > In pcb pins can only have a round shape. But there is a trick. You can > > add a pad with the same > > > > See my DIP footprints for an example: > > http://www.gedasymbols.org/user/kai_martin_knaak/footprints/generic/DIP/DIP8.fp > > > > (The oblate pins do not show in the preview of gedasymbols.org. > > Probably, because they are on the bottom layer, only.) > > This looks relatively easy to implement. I'll add this to the issues as an enhancement. > > I don't have experience on the CAM side of fabrication. But, this technical article recommends against "painting pads." > > http://www.ucamco.com/files/downloads/file/12/the_scourge_of_cad-to-cam_communication.pdf Yes, and it would be good to fix PCB Gerber generator to flash all pads (pins and vias are typically flashed). > > Does anyone else have experience with these issues on the CAM side? > > I've seen some pads that are circular at one end and square on the other end. Is there a limit to how far this technique can go? > Not really (yes there are some limits, but hard to hit in practice). It is possible to define fairly complex apertures in Gerber, or to compose them directly by flashing a few simpler ones. Now this may depend on your PCB manufacturer's equipment: for a long time the Gerber specification had a limit of ~990 apertures (from D10 to D999), the upper limit was raised to 2**31-1 a few years ago (in practice this is equivalent to infinity, can you imagine a board with over 2 billion pads, all different?), but old, and not so old equipment may have trouble handling files with thousands of apertures. Gabriel