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> > It's definitely NOT an RS-274X limitation and I can say that with 100% > > certainty. I have a colleague who uses a cheap CAD tool which allows the > > thermal reliefs to be controlled minutely on plane layers and it > > produces (274X) gerbers with no problems at all. > > > > Douglas McDonald > > Geoff, > I am not sure I buy into your explanation either. I will disqualify > myself by admitting I have little to no programming experience and > even less knowledge of Aperature generation, but I bet it can be > fixed. And if it can be fixed then it must be broke. > > Mike Reagan I think that this is a bug in Protel, and that this *can*, and *should*, be fixed; the way to do that is for thermal relief patterns having just two openings to be *"drawn"* (rather than "flashed") within Gerber files (and regardless of whether thermal relief patterns having four openings are "drawn" or "flashed" in these files). (If the PCB designer was prepared to provide an aperture list file and RS274D format Gerber files, perhaps those patterns could be "flashed" instead in those circumstances, but the onus would then be on the PCB manufacturer (and the PCB designer (to the extent of specifically bringing such apertures to the PCB manufacturer's attention)) to ensure that the PCB is still manufactured satisfactorily.) What I was saying previously was that the RS274X standard does not support "flashing" thermal relief patterns having just two openings. Given that situation, the associated arcs (of these patterns) should (normally) be "drawn" instead. I have yet to have cause to design any PCB using such thermal relief patterns, but given my understanding of the situation, if I ever did have to design such a PCB, I would figure out some way of avoiding the problem (if necessary, generating RS274D format Gerber files, and then converting these to RS274X format using a Perl script). However, it definitely is a trap for those who are unaware of the situation, so I fully agree that this is a bug, and that it should be fixed. Regards, Geoff Harland. ----------------------------- E-Mail Disclaimer The Information in this e-mail is confidential and may be legally privileged. It is intended solely for the addressee. Access to this e-mail by anyone else is unauthorised. If you are not the intended recipient, any disclosure, copying, distribution or any action taken or omitted to be taken in reliance on it, is prohibited and may be unlawful. Any opinions or advice contained in this e-mail are confidential and not for public display. * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * To post a message: mailto:[EMAIL PROTECTED] * * To leave this list visit: * http://www.techservinc.com/protelusers/leave.html * * Contact the list manager: * mailto:[EMAIL PROTECTED] * * Forum Guidelines Rules: * http://www.techservinc.com/protelusers/forumrules.html * * Browse or Search previous postings: * http://www.mail-archive.com/[email protected] * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *
