Wiring Pen
Intro: Wiring Pen
Attach a spool of wire and a hypodermic needle to a ball point pen barrel to make an aid to make point-to-point wiring easier to do. The board shown is a microprocessor system board with a 8085, 2764 and 6464 - that is, the CPU, EPROM and RAM - and some additional glue circuitry.
STEP 1: The Parts
A hypodermic needle. Get the disposable type with a plastic collar, as this will need to be cut down to make it fit in the nozzle of the ball point pen.
A (used) ball point pen. I acquired one with a metal nozzle as it would probably last longer.
The spool of enamelled wire was from a relay, 12 V changeover contacts - the rest of the relay was dismantled with care not to damage the spool of wire. Other sources are transformers and rf chokes.
Some two component epoxy to cement the needle to the nozzle.
A screw long enough to hold the spool of wire (not shown)
A (used) ball point pen. I acquired one with a metal nozzle as it would probably last longer.
The spool of enamelled wire was from a relay, 12 V changeover contacts - the rest of the relay was dismantled with care not to damage the spool of wire. Other sources are transformers and rf chokes.
Some two component epoxy to cement the needle to the nozzle.
A screw long enough to hold the spool of wire (not shown)
STEP 2: Putting It All Together
First, some copper wire was placed inside the needle to prevent its bore from closing up, and its sharp point was ground square on some fine emery paper.
Its plastic collar was cut to make it fit inside the nozzle of the ball pen, and it was fixed in position using some two component epoxy glue.
The screw was heated and poked into the side of the pen, and on cooling it was unscrewed. The spool of wire was placed on to it, and it screwed back on. The wire was led through the body of the pen and out through the needle tip.
The thin tip of the wiring pen enables it to be used to snake the wire through tight spots, and to make connections to tightly packed integrated circuit socket pins.
To make a connection, the (enamelled) wire is wrapped once or twice round the ic or socket or component pin. Heating the joint, and applying some solder will complete the joint - if you are lucky enough to find some 'self fluxing' enamelled wire. This sort of wire is coated with the sort of enamel that changes to flux when heated to soldering temperature.
I prefer to use normal, tough enamelled wire, as the chances for accidental short circuits is reduced while using this type of wire. The joint has to be heated and then the enamel can easily be scraped off using a sharp edge of a small jewelers screwdriver. Then solder is applied and the solder will attach to the freshly exposed copper.
I used to make all my prototypes this way, until the coming of the flash microcontrollers with on chip program and data memory, which does not need this scale of wiring in order to work.
Its plastic collar was cut to make it fit inside the nozzle of the ball pen, and it was fixed in position using some two component epoxy glue.
The screw was heated and poked into the side of the pen, and on cooling it was unscrewed. The spool of wire was placed on to it, and it screwed back on. The wire was led through the body of the pen and out through the needle tip.
The thin tip of the wiring pen enables it to be used to snake the wire through tight spots, and to make connections to tightly packed integrated circuit socket pins.
To make a connection, the (enamelled) wire is wrapped once or twice round the ic or socket or component pin. Heating the joint, and applying some solder will complete the joint - if you are lucky enough to find some 'self fluxing' enamelled wire. This sort of wire is coated with the sort of enamel that changes to flux when heated to soldering temperature.
I prefer to use normal, tough enamelled wire, as the chances for accidental short circuits is reduced while using this type of wire. The joint has to be heated and then the enamel can easily be scraped off using a sharp edge of a small jewelers screwdriver. Then solder is applied and the solder will attach to the freshly exposed copper.
I used to make all my prototypes this way, until the coming of the flash microcontrollers with on chip program and data memory, which does not need this scale of wiring in order to work.
50 Comments
cyber_meat 16 years ago
MichaelK113 6 years ago
That's ridiculous. What do you do if you're diabetic?
DojoMojoMofo 11 years ago
MaXoR 13 years ago
jasen 15 years ago
bgugi 16 years ago
cyber_meat 16 years ago
chalky 15 years ago
CuriousInventor.com 15 years ago
You can also buy non-super-sharp ones in bulk from mcmaster or places that sell solder-paste dispensing syringes.
AidanG 15 years ago
kenn123 15 years ago
twenglish1 15 years ago
Wafflicious 16 years ago
TheMadTinker 16 years ago
bgugi 16 years ago
neelandan 16 years ago
hayseedbyte 6 years ago
This stuff is pretty amazing and reasonably priced. They have it in basically all sizes.
https://temcoindustrial.com/28-awg-copper-magnet-wire-2-oz-mw0308-magnetic-coil-green-soderon155.html
Phil_S 8 years ago
Point-to-point wiring at the prototype stage or one-off project is far easier than techniques like stripboard. I have been doing an 8-digit 7-segment LED counter with a 24 pin Maxim driver and 28 pin Atmel (Arduino) chips. I soon gave up stripboard (too much scope for errors) and dug out my old wire-wrapping gear.
I'm glad I kept it as the component parts are available now, but inflation has taken it's toll - original wrapping/unwrapping tool £80 for example. The wire is also available as Kynar covered 0.5-mm diameter. It's biggest advantage over enamelled wire is its clean stripping and silver-plated copper core. It's much finer than stuff like CAT5e and the Kynar sheath is very tough. The stripping tool is simply a piece of thin steel with a "V" notch.
I also stocked up years ago with needles and syringes. Like many other things that used to be easily available, including most chemicals, the bad boys have queered the pitch for legitimate users - nitrous oxide will be next. ID to buy contact adhesive?? Loctite used to do blunt needles for some of their superglues and you can get stainless steel tube right down to 1/16 inch OD.
tom311571 11 years ago
HVahead 12 years ago
https://www.instructables.com/id/Precision-Wire-Stripper---new-video-links/
i would be very grateful...