How to solder / connect hobbyking 4mm+ bullets.

[neptronix]

Someone recently asked how the bullet connectors are soldered, so i figured i'd throw this up.
HXT bullets are what come on a lot of hobbyking lipo, they are easy to solder, dirt cheap, and can handle at least 50 amps.
http://www.hobbyking.com/hobbyking/store/uh_viewItem.asp?idProduct=9283

I will demonstrate the 4mm bullets here, but the same rules should apply for larger sizes.

[EBJ]

Just wanted to say thanks for this.
Made it easy, especially the part about how to get the connectors in the housing.

[rebelpilot]

I would like to add that soaking the connector bodies in water can help the assembly process, especially with the larger size bullet connectors.

[vanilla ice]

I use most of the above except with a propane torch. Ball up some solder and stick it inside the hole, heat the metal up a few seconds until the solder flows, then stick the wire in and pull the torch away.

If you don't have one of the neat solder buddy things with the clamps, you can hold the round connectors easily with the insulator part of wire crimpers. The connectors have that little step where you can hold them without worrying about them slipping.

[El_Steak]

Nice tutorial, I do it the same way.

2 more points:

1- if the other end of the wire is already connected to something (battery, motor, controller, etc.) make sure you insert the housing through the wire before you solder the connector. You can't pull the housing backwards over the connector.

2- You can drill holes (a little less than 1/4") through a piece of scrap wood and insert the connectors in them to hold them while you solder.

[EBJ]

I just use some basic pliers with rubber-bands around the grip to hold the connectors when i solder them.

[bigmoose]

nep just to clarify for folks, when you say "flux" you mean rosin flux, right! not plumbers, Zinc Chloride flux, that never stops corroding... right?

[1000w]

How do you get the bullets out of those red housings?
I have quite a few of them that I have cut off batteries and would like to reuse them.
Cheers.

[full-throttle]

How do you get the bullets out of those red housings?

I used rod pliers

Lock them around the wire and tap the connector out from the other side.

Works well but takes a tiny bit of housing off

[Stevil_Knevil]

How do you get the bullets out of those red housings?

I use a heat gun to soften the plastic housing before removing them ..might need to add a set of those rod pliers to my Lipo tool box.

Word to the OP

[Spacey]

So that is what the little hole in the side is for on those damn pain in the arse connectors, cheers dude....helps me out a lot

[auraslip]

Just wanted to ask - is flux necessary?

And I just wanted to add: Instead of holding the bullet in a alligator clip, drill some holes in a piece of wood. It's non-conductive and you can quickly solder up several plugs in a row.

[EBJ]

Just wanted to ask - is flux necessary?

And I just wanted to add: Instead of holding the bullet in a alligator clip, drill some holes in a piece of wood. It's non-conductive and you can quickly solder up several plugs in a row.

I followed the instructions and didn't use the flux (I don't like using that stuff). Worked just the same w/ no problems. My wire had the flux in it:
RA Flux , 2.2%

[999zip999]

Flux meens flow and cleaner solder joints

[Njay]

Very nice and priceless demonstration Neptronix , thanks!

I like using (rosin) flux too, on everything I solder. The fumes are an annoyance, if you don't have a fume extractor or just a blower (don't breath the fumes; breathing it regularly will cause lung diseases). But the soldering quality and easy of work... I almost dare to say "orders of magnitude" better. The stuff has a huge cleaning effect, and the solder will stick much better, deeply and quicker. The flux inside the solder is not enough.

[neptronix]

I've been using flux forever, it makes connections many times more strong.
I am using rosin flux, for sure.

Need to work on better ventilation though, i do get a whiff of it from time to time when soldering
Am glad that this helped some of ya.

[Njay]

If you have a PC case/PSU fan lying around, that's enough to suck the fumes from going into you, if put within 15-20cm of the work.

[EBJ]

If you have a PC case/PSU fan lying around, that's enough to suck the fumes from going into you, if put within 15-20cm of the work.

or you can just take a deep breath, then exhale ever-so-slightly while you solder.

[auraslip]

or you can just take a deep breath, then exhale ever-so-slightly while you solder.

The zen of or ebike building

[999zip999]

I have a used stove rectangler vent 2 speed over 1 work bench. And a fan in a kittle litter square pale with some 4in.dryer tube for intake to the front of the garage. Just have remember to turn it on.

[neptronix]

If you have a PC case/PSU fan lying around, that's enough to suck the fumes from going into you, if put within 15-20cm of the work.

or you can just take a deep breath, then exhale ever-so-slightly while you solder.

lol, i kinda do that, but it still gets in the nostrils.. and i have a fan, but it's just not powerful enough.
Soldering big gauge wires wires creates a lot of fumes as you have to use a higher heat etc.

999zip, you have an interesting idea.

[wojtek]

for the lazy or impatient or very unskillful ones:
http://www.endless-sphere.com/forums/vi ... 50#p450250

next week i am getting 4mm bullets professionally soldered to super flexible pure silicone wire harness with xt150 on the other side... Stay tuned! also balance leads...
it should take you 1 minute to build a good sized battery pack this way

[el_walto]

Thanks for the awesome pictures. They helped me a lot. A tiny bit of flux helps, especially when using 10guate turnigy wires.

[Spacey]

I've just ordered a solder bath for $23 off Ebay for dip soldering, I have so much trouble soldering 10awg RC wire with even a large butane soldering iron that I just thought dipping it into a solder bath would be better.

[wesnewell]

I was certified for soldering about 40-45 years ago when I worked in the aircraft industry. Since then I've probably made several hundred thousand if not several million solder connections. The proper way to solder is to first tin the wire. Then fill the solder cup with enough solder so that when you insert the wire the solder comes to the top. The solder should flow up the wire slightly. When you see this, you've got a good connection. To solder 4mm bullet connectors you need a large flat tip. Forget the hole, it's useless. I use a 40W Weller I've had for over 30 years with a 1/4" flat tip. Tin the tip. Hold to the side of the cup and fill with solder. Insert wire and hold until solder flows on it good. Remove iron. Let cool. Done. Flux is not a conductor. If you are using resin core solder, you should not use additional flux.