How difficult is the soldering?

Hey All
Another reason I haven’t gotten the batteries is the soldering. I only have experience soldering rc cars. Nothing as grand as the Bonkas. Especially considering the outcome of a bad job. As well, I am concerned with keeping the batteries charged properly and safely.

For a relative newbie, am I making too much out of this? Will it be simpler than I am thinking?


If everything goes right, you shouldn’t have to do any soldering. I crashed and damaged my esc, which burned the resistors in my connectors. I had to buy a heavy duty soldering gun. You’ll need like a 150 watt gun. If higher wattage better. Mine takes a while to heat the connector solder post enough to make a good solder joint. When soldering the battery connector onto the battery cables, make sure you isolate the posts from each other with plenty of tape when not soldering that post. I managed to touch either solder drop or solder gun tip to both posts and blew post off wires and melted tip of solder gun, ruined connector. I believe you can turn off discharge for the Bluetooth batteries with the smart battery app.

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Smart BMS app can turn off the charging and discharge devices in the BMS.


I presume you are considering constructing x4?
I used crimp connectors on most thick wires which some say gives a better contact. On the xt150 battery connectors i split the thick wire into 2 then used a caramelising blow torch! you need a lot of heat.


I like the crimping idea. Thanks!

I purchased a used x4, it was never flown and he did an amazing job.

SP140? Or X4?
The X4 uses the bonkas. You will need to solder some big wires. It is a skill but it can be learned. It can even be learned from YouTube. Practice before you try the actual wires and plugs in the X4 kit.
Big wires means you need to use a big (massive) tip on your iron. You can use a propane torch instead. That requires more skill/practice.

You do need a crimping tool but might be able to rent one.

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You can do it. Flux, a 50w hot iron, clean tips and get one of those magic hand tools that hold everything together. If you have to buy additional wire, try to find something similar strand wise. Also good shrink wrap and real heat gun. Soldering is a tricky skill but worth learning. Silly things like the oil from your finger tips can be defeating but the more you learn, the better you’ll be. Oh and most importantly get good leaded solder. Much easier.


Thanks for all your tips. Making me feel much more comfortable.

It’s the x4 with the xt150 connectors.