Hi,
I have a damaged motor wire from my 65161 that needs to be extended
I bought some cables but I am unable to tin the motor wire (no problem with the AWG 8 silicone cable I got)
so far I tried:
-acetone
-scraping with utility knive
-gas torch
but the wires won’t accept the solder.
what should I do?
Did you use flux? Usually scraping or sandpaper followed by acetone and a good amount of flux. I have better result with a 80W solder
thank you, I will try with flux. usally I don’t need it but probably these wires are to oxidized
Yes mate I don’t think I could have done it without flux
In the worst case you can dip wires in a molten NaOH salt bath and get rid of both oxidation and whatever type of insulation but it’s a last resort, fumes are highly toxic and the NaOH will dissolve anything it gets on - including your flesh. Wear protection, do it outside etc.
Nothing doing, neither with flux nor NaOH, nor both
I’ve had to do it on class H dual layer polyesterimide enamel wires that was impossible to clean otherwise. As said, it’s a last resort, i don’t think the common motor wires need it.
didn’t work. dont understand it.
maybe I should try with phosphoric acid as there is rust (even if I don"t know where that should come from).
ordered a new motor, maybe If I find the time I’ll open the old one and try to replace the cables
But did you melt it? Gas burner, a bunch of NaOH granulate, heat in a disposable tin can and add a teaspoon of table salt, heat ’til salt melts. Dip wires until clean.
no, i just made a strong solution of caustic soda. seems I got you wrong, took molten for dissolved.
on the weekend maybe I find time ( and place ) to try it safely
Ok, take care. That mix is truly dangerous, use full clothing, gloves, glasses/goggles, any fumes inhaled will damage your lungs seriously.
Could you document your journey ?
Today I tried the molten NaOH.
heated it up in a Tunacan on a camping stove
stirred with a wooden chopstick and dipped the cable forbsone time, then rinsed it with water: looked good
Much better than before, but still some spots that didn’t get tinned. in the picture on top a new cable for comparison
it is working, but probably needs thorough preparation I hadn’t time for today
And do it outside, the fumes are nasty
Wear swimming goggles and a good vapour mask.
Yeah, it’s hard to separate the wires so that the salt can reach each properly with some circulation. Still beats trying to scrape 500 thin wires😀
