How to attach flying leads to a component?

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Suppose I have a leaded component (LED, photodetector, whatever) that will not be mounted on a PCB, and I need to connect it to some wires e.g. 24-28AWG. What are the standard ways of doing this?

For hobby work I'd just solder wires along the component leads and cover with pieces of heat shrink. But what about production work? And low cost really is important here.

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Avoid such wiring, when possible. There are light pipes, which can be used in many cases. Also the push-button (tact switch) can be extended to reach PCB. That obviously depends on how far it is supposed to be mounted from PCB..

Tear down (or perhaps youtube) HP deskjet 35XX series - both above tricks were used in it. Actually both in one, as push-buton rod is a power indicator LED's light pipe :)

No RSTDISBL, no fun!

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Agree that its best to avoid such things, but, sometimes, you just gotta do it. Then its solder and heat shrink.

There ARE small connectors (typically of the pin and socket kind) that you can plug LEDs and such into. You can even find insulation displacement connectors that need no soldering. These are often problematic, however, because they are unpolarized and its easy to plug the device in backwards.

Jim

 

Until Black Lives Matter, we do not have "All Lives Matter"!

 

 

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In the old days...

It wasn't uncommon to find a separate PCB with the panel switches and LED soldered into the PCB, and the board mounted on extruded standoffs from the inside of the front panel. An IDC type locking ribbon cable connected the panel board to the main PCB.

JC

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kk6gm wrote:
But what about production work?
My guess is spot welders, jigs, and epoxy.
http://www.powerstream.com/spot-welder.htm
A sometimes alternative is flexible PCBs.

"Dare to be naïve." - Buckminster Fuller

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I just stripped the heatshrink off an LED on the end of a twisted pair, from the front panel of a decade old PC. Excellent solder job, whether by machine or gnome is not obvious.

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One 'trick' I've seen for LEDs is to use female keyed 0.1" connectors (like this)--the leads of the LED can go straight through and out the back of the connector and be bent over to retain it, then the connector body snaps into a plastic housing to hold the LED where you want it. Should be possible to adapt the method to anything with a single row of sufficiently long leads.

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When soldering resistors, diodes or silmilar in-line, (and also for splicing jacketed cable), I will place a "rebar" (reinforcement bar) alongside the resistor (e.g.) and associated solder joints and then cover the whole thing with a piece heatshrink tubing. For the "rebar" I have used various plastic, phenolic and similar rods, strips, etc. I have also used a piece of heavy gauge bus wire, or steel wire where the actual electrical joints are insulated themselves (for example in a cable splice).

I have also used this construction for mounting TO-92 IC temperature sensors (e.g. LM335) on the end of a 2-wire cable. Solder the cable wires to the TO-92 leads, heat shrink these individually. Then place a small piece of aluminum or brass bar stock (available at hobby stores) long enough to extend past the solder joints at one end, and position it against the flat of the TO-92 at the other end, perhaps even extended past the TO-92 a bit ( if the mounting situation warrants). Place an overall heat shrink tube over the whole thing and shrink it down tight. This results in a very sturdy assembly, you won't have to worry about those thin TO-92 wiggling to the breaking point.