Path: utzoo!attcan!uunet!yale!cmcl2!phri!roy From: roy@phri.UUCP (Roy Smith) Newsgroups: comp.protocols.tcp-ip Subject: Re: Looking for comments on the 15-pin ethernet connector Message-ID: <3356@phri.UUCP> Date: 16 Jun 88 16:04:31 GMT References: <5788@bloom-beacon.MIT.EDU> Reply-To: roy@phri.UUCP (Roy Smith) Organization: Public Health Research Inst. (NY, NY) Lines: 39 wesommer@athena.mit.edu (William Sommerfeld) writes: > screw connectors with knurled knobs which have a slot > for a screwdriver in them Yeah, but... make sure you implement it right. I've seen some connectors of the type William is talking about in which the knurled plastic grip was longer than the metal screw shaft inside and the screwdriver slot on the end was nothing more than an indentation in the plastic; stick a screwdriver in it and turn and all you end up doing is making shreaded plastic. Also, while I'm on the subject, let's make those screws and threaded sockets out of steel, not brass. I know you're not supposed to gorilla-ize the screws, but it doesn't take much force to strip the threads on a 4-40 brass screw. How much more does a steel 4-40 screw cost than a brass one in quantities of thousands? A few tenths of a cent? How much does it cost in valuable time each time you strip one and have to fight to the the connector out? Tens of dollars? And one more thing, please, please, please, please, don't attach the threaded sockets with nuts which turn in the same direction as the screws on the connectors! Anybody who doesn't know what I'm talking about should take a look at Inmac part number 853 (female mounting screws). For an example of how to properly design a threaded socket, take a look at the back of a humble ADM-5 or ADM-3 -- steel sockets embedded so they can't come loose when you unscrew the connector. Hey, I'm sorry if I seem to be getting all hot and bothered about such a trivial thing but it's time the computer industry realized that this is important and it's not worth trying to save a buck or two on the connectors for a $100,000 piece of equipment (or even a $500 one). I used to think this stuff got designed so badly because nobody really cared; once I found out that Sun actually has a component engineer in charge of connectors, I just flipped! If Sun has one, I'm sure DEC and IBM and everybody else does too (maybe bigies like DEC and IBM have whole rooms full of connector engineers?). Damned if I can figure out what they do. -- Roy Smith, System Administrator Public Health Research Institute 455 First Avenue, New York, NY 10016 {allegra,philabs,cmcl2,rutgers}!phri!roy -or- phri!roy@uunet.uu.net