I found that some electric solders (on multi-stranded cable) became brittle after a few weeks: the copper core became more fragile and eventually broke.
I am on a project of electric propulsion since 3 years, I made hundreds of welds, the problem appeared on 2 or 3 welds it is little but it is too much and I would like to understand why?
a) Soldering iron too hot?
b) Quality of the tin (I have several Chinese coils ...)?
c) Bad tinning product (it's still an old bottle that must have been 10 for )?
d) I do not know how to weld?
The cables in question are not mechanically constrained, the last ones were even completely protected by a heat-shrinkable sheath so they remained almost immobile the problem is not mechanical.
Also I also respect the instructions of amperages: the welds which break do not have too much heat ...
It looks like the break is after the tinning zone ...
Multi-stranded copper tin electrical solders that break?
-
- Moderator
- posts: 79323
- Registration: 10/02/03, 14:06
- Location: Greenhouse planet
- x 11042
Re: Multi-stranded copper tin electrical solders that break?
In general, when vibrating material is used, lugs or crimped ends are used.
The solder creates a rigid area and where the copper becomes flexible it breaks.
The solder creates a rigid area and where the copper becomes flexible it breaks.
0 x
-
- Moderator
- posts: 79323
- Registration: 10/02/03, 14:06
- Location: Greenhouse planet
- x 11042
Re: Multi-stranded copper tin electrical solders that break?
There was a little vibration but not that much ... especially that the heat-shrinkable sheath (which I cut out on the picture) kept the cables still ...
How do you put a lug on the electrical circuit in question?
Maybe I have to put less tinning product then? And that I limit it to the level of electronic plate?
How do you put a lug on the electrical circuit in question?
Maybe I have to put less tinning product then? And that I limit it to the level of electronic plate?
0 x
Do a image search or an text search - Netiquette of forum
-
- Econologue expert
- posts: 13698
- Registration: 17/03/14, 23:42
- Location: picardie
- x 1516
- Contact :
Re: Multi-stranded copper tin electrical solders that break?
It breaks at the junction soft wire / solder because of vibrations.
We must clamp the wires closer to the weld, either with fasteners or with a coating resin http://www.resilec.fr/enrobage/
Otherwise, never tried but the hot glue should do the trick locally
We must clamp the wires closer to the weld, either with fasteners or with a coating resin http://www.resilec.fr/enrobage/
Otherwise, never tried but the hot glue should do the trick locally
0 x
-
- Moderator
- posts: 79323
- Registration: 10/02/03, 14:06
- Location: Greenhouse planet
- x 11042
Re: Multi-stranded copper tin electrical solders that break?
Ah ... good if 2 answers speak of vibrations is that it must be that ... But it is not too vibrating where it is mounted ...
Ok, I will "secure" the welds with rislin collars!
I'll keep you informed!
Thank you friends!
Ok, I will "secure" the welds with rislin collars!
I'll keep you informed!
Thank you friends!
0 x
Do a image search or an text search - Netiquette of forum
Re: Multi-stranded copper tin electrical solders that break?
For a proto it can be enough but if you give a suite, it is essential to go crimping. And no matter how, there are sections to respect for it to be reliable
0 x
-
- Moderator
- posts: 79323
- Registration: 10/02/03, 14:06
- Location: Greenhouse planet
- x 11042
Re: Multi-stranded copper tin electrical solders that break?
Yes it's proto there.
Ok for crimping with male / female lugs ...
Ok for crimping with male / female lugs ...
0 x
Do a image search or an text search - Netiquette of forum
- GuyGadebois
- Econologue expert
- posts: 6532
- Registration: 24/07/19, 17:58
- Location: 04
- x 982
Re: Multi-stranded copper tin electrical solders that break?
Christophe wrote:Ah ... good if 2 answers speak of vibrations is that it must be that ... But it is not too vibrating where it is mounted ...
Ok, I will "secure" the welds with rislin collars!
I'll keep you informed!
Thank you friends!
Indeed, subject to repeated movements or vibrations, the metal cracks and eventually breaks. Fold and fold a piece of wire (it's a bit longer with the copper), it will heat to the fold, become harder and will break.
Of course, for the tin solder, it is necessary to heat as little as possible because the tin becomes brittle if it is heated too much. In addition, it binds intimately to the metal, weakening it.
0 x
“It is better to mobilize your intelligence on bullshit than to mobilize your bullshit on intelligent things. (J.Rouxel)
"By definition the cause is the product of the effect". (Tryphion)
"360 / 000 / 0,5 is 100 million and not 72 million" (AVC)
"By definition the cause is the product of the effect". (Tryphion)
"360 / 000 / 0,5 is 100 million and not 72 million" (AVC)
-
- Moderator
- posts: 79323
- Registration: 10/02/03, 14:06
- Location: Greenhouse planet
- x 11042
Re: Multi-stranded copper tin electrical solders that break?
Yes except that there are not so many mechanical constraints ...
So according to you it breaks in tinning?
Because for me it is at the tinning junction multi-strand that it breaks ... the proof in image of the connector side (same thread as the first 2 photos), it remains 1 strand surviving witness!
So I wonder if there is not (also) a reaction that weakens this junction (electro-chemical ??)
So according to you it breaks in tinning?
Because for me it is at the tinning junction multi-strand that it breaks ... the proof in image of the connector side (same thread as the first 2 photos), it remains 1 strand surviving witness!
So I wonder if there is not (also) a reaction that weakens this junction (electro-chemical ??)
0 x
Do a image search or an text search - Netiquette of forum
- GuyGadebois
- Econologue expert
- posts: 6532
- Registration: 24/07/19, 17:58
- Location: 04
- x 982
Re: Multi-stranded copper tin electrical solders that break?
Christophe wrote:Yes except that there are not so many mechanical constraints ...
So according to you it breaks in tinning?
Because for me it is at the tinning junction multi-strand that it breaks ... the proof in image of the connector side (same thread as the first 2 photos), it remains 1 strand surviving witness!
20191017_161019.jpg
So I wonder if there is not (also) a reaction that weakens this junction (electro-chemical ??)
Yes, it's the weak point. On a rigid side because of the weld, and at the junction it becomes soft, it is there that concentrates the vibration, making work the metal which finally breaks.
0 x
“It is better to mobilize your intelligence on bullshit than to mobilize your bullshit on intelligent things. (J.Rouxel)
"By definition the cause is the product of the effect". (Tryphion)
"360 / 000 / 0,5 is 100 million and not 72 million" (AVC)
"By definition the cause is the product of the effect". (Tryphion)
"360 / 000 / 0,5 is 100 million and not 72 million" (AVC)
Back to "failure, troubleshooting and repair: repair yourself? "
Who is online ?
Users browsing this forum : No registered users and 95 guests