"Phil Hobbs" schreef in bericht
...
petrus bitbyter wrote:
"Jim
schreef
in bericht ...
_Years_ ago I used to use copper eyelets in PCB's to allow soldering
in larger wire sizes.
Can't remember where I got them.
Any clues?
...Jim Thompson
--
| James E.Thompson, CTO | mens |
| Analog Innovations, Inc. | et |
| Analog/Mixed-Signal ASIC's and Discrete Systems | manus |
| Phoenix, Arizona 85048 Skype: Contacts Only | |
| Voice
480)460-2350 Fax: Available upon request | Brass Rat |
| E-mail Icon at http://www.analog-innovations.com | 1962 |
I love to cook with wine. Sometimes I even put it in the food.
They were widely used at the time but these days even the name has been
forgotten. Nevertheless, they seem to be re-invented for through-hole
plating. A German company Bungard
http://bungard.de/index.php?option=c...1&lang=english
sells them. See Through-hole and then Favorite.
I buy smaller quantities i.e. 1000 pcs at Conrad, a German company that
is
also active in the Netherlands.
http://www.conrad.de/ce/
Search for partnumber 551678
They also sell some real impressive tools but I still have the tool with
some of the 3mm eyelets I ever bought. It's only a simple center pin but
it
works good enough for the 0.8mm to 1.5mm ones. Did not try the smaller
ones
so far.
petrus bitbyter
They were forgotten for excellent reason--they're very unreliable under
temperature cycling. At high temperature, the board expands more than the
eyelet, and also softens slightly. The board cold-flows a little. When
the temperature drops, the preload on the eyelet is reduced. As the cycle
repeats, the preload on the eyelet keeps dropping until the copper trace
is in tension at low temperature, so it eventually cracks.
Using a big solder blob helps some, but you're much better off using screw
terminals.
Cheers
Phil Hobbs
--
Dr Philip C D Hobbs
Principal
ElectroOptical Innovations
55 Orchard Rd
Briarcliff Manor NY 10510
845-480-2058
email: hobbs (atsign) electrooptical (period) net
http://electrooptical.net
So one can expect the holes plated by these eyelets might face the same
problem. I'll have to think about that one.
The way the old 3mm ones were used, did not gave the problem. They were put
in perfboard without copper on it. So no traces, only wires in the holes.
Longer ones are used for rivetting. A lot of vintage tube radios have their
tubesockets rivetted on the chassis this way. Faster and cheaper then nuts
and bolds. At the time that is.
petrus bitbyter