I am working on a switch mode power supply.
I have found that using four strands for a conductor works well.
However I was told that Litz wire is the best way to go.
How do I work with say 100 strands ?
How do I remove the insulation for soldering ?
I have found that using four strands for a conductor works well.
However I was told that Litz wire is the best way to go.
How do I work with say 100 strands ?
How do I remove the insulation for soldering ?
If you adjust this one not too tight it will work OK. Otherwise precutting with a Stanley knife works too. One circular cut and one vertical one should be enough. Test a few times on a piece of that specific cable and try to cut just deep enough so without touching the copper. You can pry the cable's insulation open by the vertical cut and when you reach the circular cut you'll see that it can be removed easily.
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Make sure you buy a heat strippable litz wire. I use various litz wires in my projects, the stuff with cotton or nylon thread jacket is easily tinned, the stuff in teflon jacket you must first strip and then tin. Tinning can be done easily with a solder pot or with a reasonably hot solder iron with a little patience.
isn't you just need to let your soldered soldering tips touching the litz for let's say a few seconds until the insulation melted?
i ever repaired a sennheiser headphone cables (they're litz) and that's what i did..scratching that tiny cables just make them falling apart 😀
i ever repaired a sennheiser headphone cables (they're litz) and that's what i did..scratching that tiny cables just make them falling apart 😀
At Tektronix they had little "pots" of moulton solder that we would dip the litz wire into. It would burn off all the cloth insulation and solder all the individual wires together perfectly. Now (retired) I just melt a big glob of solder onto the last 1/4 inch and hold the solder iron under it for several seconds until I think the insulation is mostly burnt off, but the solder itself isn't yet damaged from too much heat, and there it is.
Bob, this is pretty much how I do it too, not really enough room for a solder pot in my tight work space.
The described technique worked with cotton insulation but I would not do that with plastic insulations... Either toxic gasses in the lungs or other stuff happening that will corrode your copper.
if the insulation is ok, you just solder it and that burns off the insulation in the area, that kinda litz wire is very easy to work with... not like standard wire, where is very hard to burn of insulation... and its better to strip it off before
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I've used Litz wire to make radio coils. You have to buy the right kind - the kind that you can burn off the insulation with a soldering iron. I bought mine on eBay - there are different grades - the more wires the finer each wire is and the more expensive it is.
First you unwind the cloth covering, usually two layers have to be unwound and they are wound in opposite directions. The covering is a very fine material so you remove it carefuly. Then heat the end of the wire bundle with a soldering iron tim with fresh solder, the flux helps with the process. Leave the iron on there for awhile until you've really burned it off good.
The wire kinks very easily so be careful when handling it.
First you unwind the cloth covering, usually two layers have to be unwound and they are wound in opposite directions. The covering is a very fine material so you remove it carefuly. Then heat the end of the wire bundle with a soldering iron tim with fresh solder, the flux helps with the process. Leave the iron on there for awhile until you've really burned it off good.
The wire kinks very easily so be careful when handling it.
The cloth insulation is designed to be burnt off, otherwise how would you ever use it. I haven't heard of the plastic insulation. That sounds like some new cheaper way to do it. The fumes probably are worse with plastic. I'd avoid that kind.
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The stuff I have is different, you unwind the outer covering (it's actually nylon not cloth) and then burn off the polyester coating of the individual strands with an iron.
Litz Wire 40 46 FOR Crystal SET Coil Single Layer 200' | eBay
Litz Wire 40 46 FOR Crystal SET Coil Single Layer 200' | eBay
I use Cardas Copper Litz in teflon for some of my builds, especially for the ground returns. I strip off the teflon in the usual way, then untwist the strands. When all the strands are straight, I remove the insulation with a Dremel with a stainless steel wire brush, always with the brush moving toward the end of the wire (otherwise it will wrap around the brush!). Flip it over and do it again. Repeat until the insulation is gone from all strands.
Cleans it very nicely. Then it can be wrapped around terminal strips and soldered like any other copper wire.
Cleans it very nicely. Then it can be wrapped around terminal strips and soldered like any other copper wire.
I use a Weller soldering gun on high heat (140 watts). Hold the gun tip on the bare litz and flow on solder. Do both sides to guarantee compete coverage.
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WOW - these strands are smaller than a human hair and the chances of getting all the covering off for a clean joint is pretty low - I simply don't have the skill for that - a hot iron is my recipe.
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