Resistor leads too short

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CapnCrunch
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Resistor leads too short

Post by CapnCrunch »

Hey all,

I am working on the board for a clone of 5e5 Tweed Pro. I'm using carbon comp resistors because I wanted to give them a try. I got my fiber board from Mojo and the resistors from Mouser. The problem is that about three different resistors have to span the entire width of the board and they just don't reach. Is it Kosher to solder extensions on to the leads? I was planning on using some of the lead material that I cut off other resistors that only have to span half the distance, make solid mechanical connections and then solder. I never even thought about this when I was sourcing my parts :evil:
ckpop
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Re: Resistor leads too short

Post by ckpop »

This happens alot, a manufacture will find away to cut a cost and you find out later after you buy the part. Seeing the lead is the most expensive part to the cost of the resistor, there you go.

If I had to extend to make it work just for me I would do it like this. Take longer clippings or a a good gauge solid wire, solder to the eyelet then bend up the other side and solder across it. Almost like soldering to an turrett and will be stronger then doing a side by side solder.

Just an idea
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M Fowler
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Re: Resistor leads too short

Post by M Fowler »

I've had this problem as well the leads on most of the resistors are just too short to span the whole width. I think Ckpop's method would wook good.
Andy Le Blanc
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Re: Resistor leads too short

Post by Andy Le Blanc »

The components are for mechanical insertion. The come off of rolls like a machine gun.

Adapt with added leads, You'll want to get creative with heatshrink
or use terminal standoffs to support the part around a tube socket or other
solder point.
lazymaryamps
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Phil_S
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Re: Resistor leads too short

Post by Phil_S »

CapnCrunch wrote: Is it Kosher to solder extensions on to the leads? I was planning on using some of the lead material that I cut off other resistors that only have to span half the distance, make solid mechanical connections and then solder.
I buy a few used amp chassis off of eBay every year and harvest parts. (The parts are typically incidiental -- I'm usually after transformers.) I end up with resistors that are too short. Sometimes, they are cut very close to the body. If you twist a hook on the lead and the extension, clamp them in your pliers, solder, and cover with heatshrink if needed, you'll be just fine. The best extensions are the leads you cut off of other resistors and caps, as this stuff tends to be stiff. Solid wire is next best, but tends to be softer. Use a heatsink clip if you are soldering close to the body. Of course, check the end product on a meter before you put it in what you are building, as sometimes, if the join is close to the body, the heat will hose the part.
mcrracer
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Re: Resistor leads too short

Post by mcrracer »

I used to run into this problem. Now I make my own boards 2 1/2" wide. Now all of my resistors fit just fine
rfgordon
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Re: Resistor leads too short

Post by rfgordon »

I occasionally find myself needing to add a solder point on a board for repair, mod, etc. I use a tip I got from a guy who was an electronics repair guy during the Viet Nam war.

1. Drill two small holes in the board (3/16") about 1/8" apart.
2. Using a small length of stripped solid core wire, 20 ga. is good, form a ring that passes through the holes and encircles the space between them. A double ring is best.

So then, component leads can be wrapped around the ring of wire and soldered securly. This can also be used to relocate a solder point to overcome short leads.
Rich Gordon
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"The takers get the honey, the givers get the blues." --Robin Trower
Cornelius
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Re: Resistor leads too short

Post by Cornelius »

On elongating legs, i'm with Phil_s; 'twist a hook on the lead and the extension, clamp them in your pliers, solder, and cover with heatshrink if needed.' :) (Or with the cloth-cover from new 'vintage' wires. ;) )
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Structo
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Re: Resistor leads too short

Post by Structo »

Yep, make a small hook on the resistor lead and a hook on a wire or clipped off lead, hook them together and squeeze tight with pliers.
You want a good mechanical bond there, the solder is just glue to hold it together. :D

I can't remember where I saw them but somebody had some CC resistors that said they had longer leads.
Maybe they were NOS Allen Bradley resistors.
If I think of the place I'll post it.
Tom

Don't let that smoke out!
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Sonny ReVerb
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Re: Resistor leads too short

Post by Sonny ReVerb »

Weber's are longer, but they're metal film:
Our metal film resistors have leads that are (12mm) 1/2" longer than typical resistors to accomodate insertion in fiber eyelet boards and other wide spaced connecting points in point to point wired amplifiers, effects, and other products.
I think Riken's had long leads, but they went TU...
"The blues is the roots, the rest is the fruits." - Willie Dixon
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