Short legs on transistors

Johnnyorange500

Johnnyorange500

Active member
I’ve just managed to salvage some Nkt transistors from an old radio and the legs are too sort after cutting them free. I’ve tried to fit them into an arbiter fuzz face replica pcb but I’m struggling to fit them all in flush! Any ideas what’s the best way forward with these or are they a lost cause. Pretty gutted really if I’m honest!! Here’s a picture.
 

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Johnnyorange500 said:
Yeah, I did have that at the back of my mind. I’ve heard of this before! What’s the best way to do this.. sorry for my ignorance but never done it before.
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You need heat sinks and a quick touch with the iron. A very small diameter lead forming mandrel helps a lot but isn’t strictly necessary. I clip heatsink to lead of transistor, crimp the new lead onto the heatsinked lead, and then solder the crimped joint.
 
Laundryroom David said:
You need heat sinks and a quick touch with the iron. A very small diameter lead forming mandrel helps a lot but isn’t strictly necessary. I clip heatsink to lead off transistor, crimp the new lead onto the heatsinked lead, and then solder the crimped joint.
Click to expand...
Cheers buddy.. sounds a bit daunting, but will look into it. I’m sure I will get my head around it eventually.
 
Basically, I try to wrap the two ends together and crimp them tight before soldering. I have no idea if this is the correct way technically, but it has worked fine for my purposes. I rushed and used lead free solder, so it ain’t pretty but as you’ll see, it works. Hope this helps! If not lemme know and I’ll try to fill in more blanks.

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Laundryroom David said:
Basically, I try to wrap the two ends together and crimp them tight before soldering. I have no idea if this is the correct way technically, but it has worked fine for my purposes. I rushed and used lead free solder, so it ain’t pretty but as you’ll see, it works. Hope this helps! If not lemme know and I’ll try to fill in more blanks.

View attachment 58209View attachment 58210View attachment 58211View attachment 58212View attachment 58213
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That’s great. Thanks again. What wire is best to use?
 
Will be that guy, but it's in kindness.
Next time the legs look short, don't snip the, desolder them.
Quick dab of fresh leaded solder, taking your time between additions and using a heat sink(alligator clip on the leg works well). You want the old solder to just liquidy without flowing as much as possible to avoid flowing too much toward the component/opposite side of the pcb.
Flux pen won't hurt.
Then, if you have a desoldering gun, go for it. If not, grab your braid and apply ample flux to the clean braid. Desolder hot and fast, IMO. Always use clean braid. Trim the dirty stuff and start fresh each time, having ample braid on *both* sides of your tip. Give the solder twice the path.

As long as you are avoiding prolonged heat and spacing your attempts to allow cool down, the components will be fine.
Remember, someone put them in the board with short legs and they lived all these decades.
I know this wasn't the original question but, this so the way.
Practice on a few non-worthy components.
 
jwin615 said:
Will be that guy, but it's in kindness.
Next time the legs look short, don't snip the, desolder them.
Quick dab of fresh leaded solder, taking your time between additions and using a heat sink(alligator clip on the leg works well). You want the old solder to just liquidy without flowing as much as possible to avoid flowing too much toward the component/opposite side of the pcb.
Flux pen won't hurt.
Then, if you have a desoldering gun, go for it. If not, grab your braid and apply ample flux to the clean braid. Desolder hot and fast, IMO. Always use clean braid. Trim the dirty stuff and start fresh each time, having ample braid on *both* sides of your tip. Give the solder twice the path.

As long as you are avoiding prolonged heat and spacing your attempts to allow cool down, the components will be fine.
Remember, someone put them in the board with short legs and they lived all these decades.
I know this wasn't the original question but, this so the way.
Practice on a few non-worthy components.
Click to expand...
No worries pal. It’s very much appreciated. Thanks for the detailed description. 👍🏻
 
With the old radios, I've started snipping away the circuit board until each transistor or GE diode is on its own island, and then try to isolate each lead, if it's feasible. Then, it usually takes just a flick down the lead with the soldering iron to free the whole lead and leave it clean. It's a slow process, and I've broken a couple diodes with overly violent snips. But it's a weird kind of fun.
 
Solder-extensions on the legs — this is one place where sockets are a distinct consideration.

It's been my experience putting leg extensions on a pot that once I tried to solder the extensions into the PCB, they would always heat up enough to destroy the extender/pot-leg connection — regardless of attempts to bleed off temp with some sorta heatsink.
 
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