Big Rock Big rock v3 battery connection melting together

[Ozbit]

Hello there and thanks in advance all help will be greatly appreciated.
I have the 3s bigrock v3 I've had it a little under a year now and it's taken quite a lot of abuse. Mostly easy to fix problems like new chassis diffs shocks and a arms even for a noob like me. For the second time yesterday tho my esc and battery connection have fused together and I'm unable to separate them.the first time I chipped most off the plastic off the outside plug but was still unable to separate. I purchased another esc and took the hit of loosing a battery. FYI a zeee 8000mah 100c quite a hit for me.
Anyway been running it with new esc for 3 months ish with no problems then yesterday it happened again. Please can anyone tell me firstly why this is happening and secondly what I can do to solve this issue. Maybe uprate esc? Any and all help would be great
Thanks

 

[GraniteFox]

I would guess you have a short going on between the esc and battery connection. Look for stripped wires or loose connections. If nothing found I would replace the connector on the esc as it's very likely gone bad. Just solder on a new one. Very possible you have a bad solder joint in the connection. Never had this issue but just an educated guess.

 

[Ozbit]

I would guess you have a short going on between the esc and battery connection. Look for stripped wires or loose connections. If nothing found I would replace the connector on the esc as it's very likely gone bad. Just solder on a new one. Very possible you have a bad solder joint in the connection. Never had this issue but just an educated guess.

Hello and thank you for you reply
I have 2 escs and battery's welded together now also I have no experience in soldering or the tools required and not sure I want to risk losing another battery if it happens again would uprating the esc help ? Sorry I am new to rc

 

[GraniteFox]

Updating the ESC will very likely do nothing to help this issue. Learning to solder would be very helpful if you like the hobby and plan to grow with it. It's really not that hard. You can also take it to a local hobby shop and they can do the work for you.

 

[Hector_Fisher]

Electrical heat is caused by high amperage (not super likely in your case) or high resistance. A bad solder joint is what I would be considering as the culprit here, as those can cause alot of resistance. FWIW, i had never soldered before in my life until i took up this hobby. Had the learn the rough way. Bought some extra connectors and practices several times before making my first battery connection. Plenty of videos out there and some decently cheap soldering irons.

Alternatively, you could check with your local hobby shop to see if you can pay for them to do it.

 

[Ozbit]

Electrical heat is caused by high amperage (not super likely in your case) or high resistance. A bad solder joint is what I would be considering as the culprit here, as those can cause alot of resistance. FWIW, i had never soldered before in my life until i took up this hobby. Had the learn the rough way. Bought some extra connectors and practices several times before making my first battery connection. Plenty of videos out there and some decently cheap soldering irons.

Alternatively, you could check with your local hobby shop to see if you can pay for them to do it.

Thank you for your reply I would give soldering a go but unsure what I would need. Ie what kind of watt soldering iron I would need would I need high watt? Looking at them they start about 80watt to 300.i assume it's got to be high temp soldering or my plugs will melt again? Sorry I know nothing about soldering or lipos or rc lol but willing to learn. Thanks for your help

 

[Hector_Fisher]

Lots of info on the forum about that. These are the first that came up, I'm sure you could find even more.
https://www.arrmaforum.com/threads/which-iron-do-i-need.66375/
https://www.arrmaforum.com/threads/...-how-to-practice-before-the-real-thing.69732/
https://www.arrmaforum.com/threads/what-soldering-gear-do-i-need.54252/

First steps would be 1) decide what iron to get, 2) watch some videos on how to solder, 3) practice.

 

[Ozbit]

Lots of info on the forum about that. These are the first that came up, I'm sure you could find even more.
https://www.arrmaforum.com/threads/which-iron-do-i-need.66375/
https://www.arrmaforum.com/threads/...-how-to-practice-before-the-real-thing.69732/
https://www.arrmaforum.com/threads/what-soldering-gear-do-i-need.54252/

First steps would be 1) decide what iron to get, 2) watch some videos on how to solder, 3) practice.

I was kind of hoping for a reason why this happened twice but months apart and a solution to stop it happening again rather than soldering battery and esc to use again and probably with the same outcome. I thank you for your help and I'm looking at giving soldering a go but why is this happening?

 

[GraniteFox]

I have used this for a couple years with no issues. https://www.horizonhobby.com/product/trakpower-tk950-soldering-station/DTXR0950.html

Be mindful when soldering lipo battery connectors. Don’t want the positive and negative accidentally touching each other. Do one side at a time and tape off the other while soldering. Watch a couple videos….

 

[Hector_Fisher]

I was kind of hoping for a reason why this happened twice but months apart and a solution to stop it happening again rather than soldering battery and esc to use again and probably with the same outcome. I thank you for your help and I'm looking at giving soldering a go but why is this happening?

As i was saying earlier, a bad solder joint causes lots of heat. My most likely suspect is poor quality solder joints from the factory. (either battery or ESC)

Usually if bad solder joints continue to be a problem, they get hot enough to just de-solder themselves and come apart. However, if the wires are positioned in the right way, it might prevent the joint from coming apart even if the solder gets hot/soft. The next biggest weakness is the connectors, so if the joint can't come apart, and heat keeps building, you could theoretically create an issue where the connectors themselves get fused together.

Is the plastic around the connectors melted?
Do you have any pictures of the fusing?
Are the connectors clean? (dirty connectors may contribute to higher resistance -- less metal to metal contact)

 

[Ozbit]

As i was saying earlier, a bad solder joint causes lots of heat. My most likely suspect is poor quality solder joints from the factory. (either battery or ESC)

Usually if bad solder joints continue to be a problem, they get hot enough to just de-solder themselves and come apart. However, if the wires are positioned in the right way, it might prevent the joint from coming apart even if the solder gets hot/soft. The next biggest weakness is the connectors, so if the joint can't come apart, and heat keeps building, you could theoretically create an issue where the connectors themselves get fused together.

Is the plastic around the connectors melted?
Do you have any pictures of the fusing?
Are the connectors clean? (dirty connectors may contribute to higher resistance -- less metal to metal contact)

The chipped away plug is the first time it happened but before chipping away there was no signs of fusing the unchipped 1 is the second this also has no signs of fusing so it looks to me like it's the battery connection that is the fault what do you think?
Thanks again for your help

 

[Hector_Fisher]

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View attachment 358416

The chipped away plug is the first time it happened but before chipping away there was no signs of fusing the unchipped 1 is the second this also has no signs of fusing so it looks to me like it's the battery connection that is the fault what do you think?
Thanks again for your help

Unless the battery connector was somehow touching something very hot that exacerbated the situation (perhaps touching the motor can?) then I would have to assume it was a poor connection or solder joint that lead to high resistance and lots of heat.