Relay-Version: version B 2.10 5/3/83; site utzoo.UUCP Posting-Version: version B 2.10.2 9/18/84; site bmcg.UUCP Path: utzoo!watmath!clyde!bonnie!akgua!whuxlm!harpo!decvax!ittvax!dcdwest!sdcsvax!bmcg!yrdbrd From: yrdbrd@bmcg.UUCP (Larry J. Huntley) Newsgroups: net.micro,net.arch Subject: Building One-of-a-Kind Systems (Wire-wrap) Message-ID: <1700@bmcg.UUCP> Date: Tue, 4-Jun-85 13:03:24 EDT Article-I.D.: bmcg.1700 Posted: Tue Jun 4 13:03:24 1985 Date-Received: Sat, 8-Jun-85 02:18:17 EDT Organization: Burroughs Corp. ASG, San Diego, CA. Lines: 73 Xref: watmath net.micro:10695 net.arch:1334 Howard Hull (hull@hao) writes: (Concerning AC powered wire-wrapping tools) > > 1. If you press the gun too firmly down around the base of the post, > the wire will not feed properly, and (if you are lucky) the... > > 2. If you suffered from linear withdrawal symptoms while doing the > wrap, and you thus lifted the gun slightly while wrapping, you will > have an even, but nonetheless a *stretched* wrap. Since a... > > 3. Always strip wire_wrap wire with a "gauged" stripping tool. Just > pulling the wire from the reel until it breaks, or use of a... > > Regards, Howard Hull It is clear that Howard has made more than a few wraps in his time. All of his points are valid and lack of attention to these details can cause hours or days of grief when debugging begins. Luckily, there are solutions to these problems. "Mashed" wraps (where the gun was held on the post too forcefully and the wire is overwrapped) and "stretched" wraps (where the tool was moved off the post too soon) can be eliminated by using wire-wrap guns with what is variously called a "Back-Force Nosepiece" or an "Anti-overwrap Device". This is a spring loaded widget that sits on the front of the gun; the wire-wrapping bit is mounted into it and when the whole assembly is put over the post and as the wrap is made, the bit is backed off of the pin just the right amount. You (the operator) don't have to really do anything but hold the gun straight over the post and pull the trigger. This accessory adds about $10.00 to the cost of a wire-wrap gun. Is it worth it? Do birds have beaks? Proper strip length, lacks of crimps in the wire, etc., etc., can be had by using a special wire-wrapping bit called a "cut, strip, and wrap" bit. This marvel of chemical machining replaces the standard bit and sleeve in a wire- wrap gun. You take the unstripped wire, push it up into the bit, as in a regular bit, put the tool over the post and pull the trigger. As the wrap is being made the tool cuts the wire to length, strips off the insulation, and wraps the wire around the post. Repeat for the other end. Repeat for next wire. All the operator has to do is cut the unstripped wire to some- where near the right length (slightly longer than needed.) It's great. We have used them here at Burroughs ASG for 5 years; they've been trouble free. Now about the price. These little mothers cost somewhere between $125 -- $225. Unless you're the world's most affluent hobbyist, then it's unlikely that you'll buy one for personal use. However, in a development lab, I feel like these are indispensible. I like to trouble-shoot circuits; I do NOT like to trouble-shoot wiring problems caused by being too cheap to buy the right equipment. This thing here is the right equipment. If you're on a tight budget, buy a cheaper DVM or something and use the difference to get one of these. You'll never go back to the ordinary bits and sleeves. If any of you want addresses of places these things can be had, drop me an electronic line; I'm no salesman, but I like to think that I know a good product when I see one. If we buy enough of these things, maybe the price will drop and then we can buy more and the price will get lower and ....... Hey guys, isn't this discussion more fun than "Re: Re: Re: Re: Re: 286 "C" Benchmark Needed" or "Why I Like The 680xx" or "Dog Pile on Intel!"? More useful, too. Yours for better one-of-a-kind systems, 'brd P.S. I just noticed that I used 'guys' 5 lines ago. Is that sexist? Perhaps I should have used 'guys & gals'? 'Folks'? I'm so distraught. -- Larry J. Huntley Burroughs -(B)- Corporation Advanced Systems Group MS-703 10850 Via Frontera San Diego, CA 92128 (619) 485-4544 -*- "Dear Friends, It's 'ORGAN LEROY' at his organ again." -*-