A Solid Soldering System, and Cordless

George S.

Well-Known Member
A Great DIY Tool

Building a bike into an ebike is a great way to get the best value for the dollars you spend. On the other hand, there are some things you want to do right. If you follow what might be called industry standards, a DIY is comparable to any bike in terms of integrity of the build. This is fairly simple stuff. You might need torque arms. You want very sound and waterproof connections. You want brakes that match your speeds.

A DIY bike can have a motor from one company and a battery from another. You can have a battery for a long time, and you can change or add bikes. You might like a second ebike, say a bike for rougher terrain, or a folder. If you have an ebike battery and just need a motor, another bike can be very cheap. Different ebikes are different experiences. Different motors, hub or center drive, offer different experiences and capabilities.

The key to sharing or just using motors and batteries is obvious. It comes down to connectors. Ebikes can use a lot of power, a lot of amps, so twisting wires together is not a great idea. The general procedure is to solder the wires together and wrap the solder splice with heat shrink.The cheap and basic connectors include the XT60 and the Deans connector. These are solder connectors. You can buy these at Amazon, on Ebay, and at Hobby King.

If you are comfortable with soldering connectors and select appropriate wires and connectors, you have more options for your battery. Most ebike shop batteries are virtually locked into the bike you buy. You may not know much about it, and it’s not open for you to use as a big storage battery. A DIY battery can be used and charged any way that you want. If you have a 48 volt battery, with some simple soldering, you can make a 12 v power center for blackouts or camping. There are 48v to 12v converters on Ebay for $15, but you have to be able to make the connections. Basically you take the output connection from the battery to your ebike motor, and put that on the input to the 12v converter. Now you can run a lot of 12v stuff. You can buy 48v to 120vac inverters, as well, but they are fairly pricey. In a pinch you can run the 48v to 12v converter and plug a $20 12v inverter into that. It’s a bit messy, but in a long power outage, it might be OK.

My choice for anything beyond the most casual soldering is the Milwaukee M12 cordless solder gun. I’ve bought other cordless soldering systems, like butane soldering irons, but they just don’t work very well. The M12 delivers a lot of heat, and it warms up and stays on. The downside is a short battery life. There are knock-off batteries online.

Connectors require some precision to solder. You want a fairly small solder tip, but one that gets hot enough without melting stuff. The M12 is about right for splicing 10 gauge wire together and putting an XT60 on the ends. Connectors that you control open up the battery to the things you may want to do. You can make your own chargers with CC-CV power modules, and plug the input into solar panels, which are now dirt cheap. It takes some study, but all the building blocks are out there to do several things with an ebike battery. . Little modules that convert voltages to USB type sockets are cheap, but check the top voltage. You can power almost anything that uses DC with voltage converters.



Well-Known Member
I used the Craftsman 130 W solder pistol to do my XT connectors, which since it is AC powered doesn't require a new battery every 2-3 years used or not. My gun is 40+ years old. Since sears is dying fast, the equivalent 125 W pistol unit from weller should be a good option. It was $37 in the last mcmelectronics catalog (now defunct). For absolutely cordless operation, a butane cartridge iron from bernz-o-matic worked well at the factory I used to work at. Rarely available at home depot, and I do not recommend the ****ese knock offs, mine leaked the tank dry in a year.
I found XT connectors melt easily so to keep the pins straight I plugged my second one into the mating connector while soldering. Don't plug it into the battery while you do this, the soldering iron tip may be (should be post 1985) grounded.
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