trouble soldering loose cells to make stick pack

[bangstick 0]

I have been for the last 20 mins trying without success to solder the joining straps to my new set of racing cells. I have gotten a nice bit of solder on both ends of the strap and have been trying heat the back of the strap with a 100w soldering gun hoping the solder on the other side up against the cell will melt but it will not no matter how long i keep the gun on it. The body of the gun has started to melt lol. This is my first time making my own stick pack and could do with some soldering tips, cheers

[terry.sc 16]

Firstly a soldering gun is the wrong tool for the job. It might be

rated at 100W but the wire tip cannot hold enough heat to solder onto a

battery pack. You really need a proper soldering iron with a large tip

that holds heat as the battery acts as a very effective heatsink,

drawing all the heat from the irons tip. A soldering gun just cannot

heat the tip up fast enough to keep it hot. Also if you haven't already

coated the battery with solder when you put the bar on it you will

never make a joint.

I use a Weller 75w iron which is designed for this sort of job, try

searching for the Weller sp80l for its replacement. make sure both ends of the cells

and the battery bars has been tinned with solder first and a decent soldering iron

should make the joint in only a second or two. Keeping the iron on the

battery any longer than that will overheat the battery and damage the

chemicals inside it. It also makes soldering wires on a motor simple,

even on V2s.

To make sure I have tinned the cell properly I use a sanding drum in a

Dremel to scuff the can ends before cleaning them with alchohol to degrease them before soldering. I also

find a battery jig makes life so much easier by holding the cells in

place. Much simpler than trying to balance a pack on end while holding

a battery bar, iron and solder at the same time.

[bangstick 0]

Cheers Terry,

  I did get the feeling the tool i had was not man enough for the job.

[Razer 0]

I do it like terry describes, but without the alcohol & I use a 40W Weller SP40 without any difficulty.

[jozza 1]

http://www.balakracing.com/buildingbatterypacks.htm gives a nice simple guide for soldering packs together, or for a more detailed guide take a look at http://www.rccaraction.com/rc/articles/build_battery.asp. A gun won't be sufficient for the job, it must be an iron and must be of a reasonable wattage (50W+) for it to work. If you follow the instructions above it will be easy to do, and the Deans jig is well worth buying if you are soldering cells, makes the job 10 times easier than trying to do it without...

[bangstick 0]

Cheers jozza,

  Still having aggro im afraid. Liam from GM models where i bought the cells from very kindly lent me a pucker 100w soldering iron with a nice meaty tip which soldered the straps on lovely despite my having trouble balancing the cells and soldering them lol. My new problem is the fact that no matter what i do the wires just will not take, they are quite thick and im having trouble getting the solder to take to them before i try and attach them. I think i have ruined my new pack by overheating  the two end cells which i am slightly peeved about. Lesson learned = buy ready made ones

[bangstick 0]

On further reflection im annoyed with myself, what i might aswell of done was take my 100w soldering gun and held it for 10 mins on top of a 20 pound note then repeated this procedure shortly afterwards with a 10 pound note. I am pretty certain i have totally ruined my nice reedy racing cells AAAAAARRRRRGH!!!!!!!!

[stuie-t 0]

you need to use a good rosin flux for the solder to take properly.  It is available in many forms, but I use one that is in the form of a permanent marker.  Just wipe the areas to be jointed before tinning.

The one i use is called "Rosin Flux Dispensing Pen" by circuitworks.  Cost a few pounds from Maplin.

[bangstick 0]

So just draw on the wire and cells with a marker pen and that acts as a flux? I should be god at soldering im a plumber for crying out loud lol. Cheers BTW ;-)

[Tinno 0]

You are not alone in your soldering troubles, so don't feel too bad with yourself.

I have had similar problems in the past.

1) soldering gun is not thr right tool for the job (I have blown my gun after trying to use it)

It did the job fine for the female deans connectors, but the males (with more metal to heat, were just too much)

2) With your 60w+soldering iron, tin the wire first.  Heat the wire, then add a decent resin core solder to the iron, and coat the wire with the solder.

3) then tin the other itne you are doing (in my case deans connector, in your case, battery terminal.

4) Add slightly more solder to the battery so that the solder is proud, then rest the wire on the top, and apply the iron to the wire the heat of the iron should melt the solder below and the wire will sink through, then take off the iron and hold the wire / plate in place.

I found it slightly easier to tin the wire, then heat the pre tinned end directly with the iron, I would then add the tip of the wire to the soldering iron to get it warm / hot and then lift the iron slip the wire under and reapply  firm presure. I have a few "helping hands " devices to hold things steady.

Hope that this helps

 

[bangstick 0]

Excellent advice tinno but alas i think my cells are knackered now due to my failure to flux the wire to get them tinned properly, Oh well my boss says the best way to learn is by losing money. Apparantly you learn pretty quick that way ;-)

[stuie-t 0]

added the brand details of the flux pen to my post above.

You really should know what you are doing if you are a plumber! []

[bangstick 0]

Lol, Cheers.

My pipework might not conduct electricity but it also wont leak.

[bangstick 0]

Im glad you updated that post as i was just about to attack my cells and wire with a black marker pen lol, Oh and BTW you can see my soldering skills if you check my post in the What do you all look like? thread.

[stuie-t 0]

hey it might work []

[Terminal-Junkie 0]

Cheers jozza,

 

Still having aggro im afraid. Liam from GM models where i bought the

cells from very kindly lent me a pucker 100w soldering iron with a nice

meaty tip which soldered the straps on lovely despite my having trouble

balancing the cells and soldering them lol. My new problem is the

fact that no matter what i do the wires just will not take, they are

quite thick and im having trouble getting the solder to take to them

before i try and attach them. I think i have ruined my new pack by

overheating  the two end cells which i am slightly peeved about.

Lesson learned = buy ready made ones

Ouch!  Glad to hear the soldering iron did the job and not so glad

to hear about the cells :-(  If any of the connectors etc are

still in packets etc we can stick them back on the shelf and credit you

back - Sorry its not much but might help soften the blow....

Cheers

Liam

[bugged 6]

I use flux, Its a little yellow pot, Put alittle on the bare wires and tin the wires with your soldering iron./ Flux helps the solder flow. Great stuff !

[bangstick 0]

Thanks liam, but i think they might be handy to just keep in my box for an emergency. Im sure if you know what you are doing, making your own stick pack is easy but alas i am a bellend when it comes to stuff like that [:'(]. Oh well i take great comfort in knowing i will have a blast with my new blitzer beetle down you neck of the woods at the next KB, BTW will you be ok without your soldering iron until then to save me a trip?

[Terminal-Junkie 0]

Thanks liam, but i think they might be handy to

just keep in my box for an emergency. Im sure if you know what you are

doing, making your own stick pack is easy but alas i am a bellend when

it comes to stuff like that [:'(]. Oh well i take great comfort in

knowing i will have a blast with my new blitzer beetle down you neck of

the woods at the next KB, BTW will you be ok without your soldering

iron until then to save me a trip?

Hi,

Sorry for the delay in getting back to you - been that busy with the

shop re-shuffle and track that i've not had the time to scratch my ***

let alone risk life and limb with the soldering iron so drop it back

when your next passing.

Cheers

Liam

[bangstick 0]

Hi Liam,

I actually put the iron in my car ready for you on sunday as i assumed you would come to the KB on tour. Not seeing you there made me forget all about it until i got home to unload the car and 30 odd kilo's of sand i picked up throughout the day lol. See ya soon mate

[Terminal-Junkie 0]

Hi Liam,

I actually put the iron in my car ready for you on sunday as i assumed

you would come to the KB on tour. Not seeing you there made me forget

all about it until i got home to unload the car and 30 odd kilo's of

sand i picked up throughout the day lol. See ya soon mate

Hi Mate,

No probs, was looking forward to the bash, keept looking on here for

the date and ended up missing it due to moving a few tons of soil at

the track - know which i'd rather have done lol!  The action shots

look pretty good and one way of the other i shall be at the next one,

see what bits on the Boomerang break this time.....

Cheers

Liam

[bangstick 0]

Any pics of this new track yet liam?

[Terminal-Junkie 0]

Any pics of this new track yet liam?

Hi Mate,

Yup, just a few lol!  The main site is at....

 http://www.rcoptions.com/thunderroad/

From there you can view the photo gallery, bash / race dates, race

classes etc.  Ignore the design, its been changed, the shape is

roughly the same but everythings been made wider and faster :-) 

Looking good for the April 30th bash, if you can make it the more the

merrier :-)

Cheers

Liam

P.S

Any ideas when the next kent bash is?  Will try and make it this time.....

[bangstick 0]

Not sure mate, best to keep an eye on the KB thread, Chris updates it as soon as he knows himself. I think it will be at the normal venue next time though.

[r6stu 0]

I just had to get two new cells for my new unused pack as I dropped the iron onto two cells while fixing a diff pack!

Had to put into the fridge to cool down!

Then 1st time I use the pack one cell vented! and I check the voltage of the others and the cell next to it was also dead!

Luckly the cells are ony £2.75 each on ebay for GP3300 cells!