Wire wrapping question - Page 1
Forum section: electronics / projects

author: ArcticBlue03
author_rank: Newbie
timestamp: May 21, 2013, 04:13:49 pm
content: I am working on a project at work and we have been discussing the possibility of wire wrapping our connections instead of using a connector. The problem is I can't really find any information on companies that still use this technique in mass production. I know the telephone industry used to use it on phone lines but it doesn't seem like it is still used very often. Does anyone have any kind of experience using this technique in mass production or some pros and cons?Here is a video for those who don't know what I am talking about.Thanks for any help.

author: Paul Price
author_rank: Super Contributor
timestamp: May 21, 2013, 04:47:24 pm
content: Too much costTo much time and effortThe wire is expensive.It is easy for a technician to make a mistake in a jungle of WW wires.It is slow to accomplish each connectionEasy to create a short circuit or break a ware and create an open circuit that is difficult to see.Boards are not consistenly made in perfect condition unless by machine controlled robotic WW.Difficult to identify points for troubleshooting.Limits connection to each point of 2 or 3 max wires.Creates an additional level of connection to devices.Long wires have high inductance that are not laid upon a ground plane to shield and present itself at the best impedance.WW causes ringing.Not suitable for analog circuits as all this wire creates noise or else can be a virtual sponge for noise.Does not work with small SMD devices that are the standard package for any new application.If WW is used, the finished device is heavy and bulky.Versus: A PCB prototype can be created in a modern setting in a matter of minutes or else breadboarded as quickly, but otherwise WW is ok. I don't think anyone sane, anywhere in the world is still mfg'ing anything with this method anymore..

author: smashedProton
author_rank: Frequent Contributor
timestamp: May 21, 2013, 04:53:57 pm
content: Wire wrapping wire only exists nowdays for bodge wires

author: C
author_rank: Super Contributor
timestamp: May 21, 2013, 04:54:05 pm
content: From what I see in that video that guy will have a lot of connections going bad!look at wikipedia and see if you can spot ithttp://en.wikipedia.org/wiki/Wire_wrapC

author: SeanB
author_rank: Super Contributor
timestamp: May 21, 2013, 05:11:09 pm
content: Hard to get the tooling and connectors these days, only available as old stock or surplus/used. You can try using IDC connectors and ribbon cable if needed, easier to use and available.

author: madires
author_rank: Super Contributor
timestamp: May 21, 2013, 05:20:59 pm
content: Quote from: ArcticBlue03 on May 21, 2013, 04:13:49 pmOver here most carriers moved to LSA+ long time ago. But sometimes I still see wire waps where tons of lines are connected to a switch/monitoring board. It gives a more solid and long-lifetime connection but is a dying art.

author: ddavidebor
author_rank: Super Contributor
timestamp: May 21, 2013, 07:01:53 pm
content: Quote from: ArcticBlue03 on May 21, 2013, 04:13:49 pmYou should use 2.54mm pitch flat single core wire.

author: andyturk
author_rank: Frequent Contributor
timestamp: May 21, 2013, 10:44:30 pm
content: Quote from: ArcticBlue03 on May 21, 2013, 04:13:49 pmI've got no idea about mass production, but I did a fair amount of homebrew wire wrap in the 70s.The video tutorial seemed lacking. First, you'd never try to wrap directly to an LED lead, at least, not without putting a twist on the lead itself. I think the ww concept was limited to connecting specially designed sockets that had long pins.Also, stripping each end of the wire is a lot of work. There used to be a special kind of wire where the insulation was designed to be pierced by the sharp corners of the ww sockets. So, you'd just put your unstripped wire into the tool and twist it onto the pin. The tension of the twist cut the insulation and made an electrical connection. Unfortunately, that style of ww was pretty easy to unravel if there was any sort of movement.

author: PaulAm
author_rank: Frequent Contributor
timestamp: May 21, 2013, 11:39:19 pm
content: That is a terrible wirewrap connection.A properly done connection will have one or two turns of insulation around the post and the remainder will be evenly wrapped. When wrapped with the correct tension the corner of the post will bite into the wire and form a gas tight joint that is quite reliable. You need a _good_wire stripper, possibly thermal depending on the type of insulation, and a decent wire wrap tool, either electric or pneumatic. I liked the pneumatic ones; they were small and easy to handle. A good wirewrap gun was essential to making consistently good connections. Hand wrap is simply a disaster.Wirewrap was used for low production boards in the late 70s through early 80's. I still have some boards from a mainframe computer built like that. I agree with most of Paul Price's criticisms and the shortcomings are much of the reason it's fallen out of favor. It really doesn't work too well when you get signal speeds much over a few MHz. With the right tools, however, it can be fairly quick and reliable. I used to prototype with wirewrap and I still have the tools, but I haven't used them in years.

author: westfw
author_rank: Super Contributor
timestamp: May 22, 2013, 01:15:44 am
content: There was a competing technology, multiwire, that looks like it might still be available via Hitachi:http://www.hitachi-chemical.com/products_pwb_05.htm