Battery pack assembly.

Best bet is a damned big tip that holds a lot of heat.

The bigger the iron. the shorter time it tales to solder

The message from The Natural Philosopher contains these words:

Got an 80 watt with a chisel tip so may try that on some kwackered cells first or old none-rechargables to get the hang of it,

regards, Terry

Back in the early days of solid state devices (eg transistors) to avoid overheating we just wrapped cotton wool soaked with metho around the device and used pliers as a heat sink for the leads.

So, piece of cloth soaked in metho around the battery while soldering (and of course following the philosophers advice) might help

David

The Natural Philos> Terence Lynock (MSW) wrote:

The message from quietguy contains these words:

Hi Dave, when I have flat batteries (non-rechargable) out of TV remotes etc instead of throwing them away I will practice on them until I find a safe and quick method, I have an 80 watt iron and can make a special tip if need be to a shape that suits me and puts a lot of heat in quickly using low-melting point solder and cut my tags from copper sheet and pre-tin them. The problem I have is a couple of powered gliders with very narrow fuselages so they need a stick battery pack of two cells wide x three cells long or three cells in a triangular pattern x two cells long to fit,

regards, Terry

We just used hot irons..

You can buy 'hammerhead' tips for irons.

The idea is - and I have never done it - you pre-tin your cells first with plenty of solder, and then place them in a half tube or similar groove, and spring load em together with a rubber band. Then you force a pair apart, stick the hammer head in between and once the solder is good and wet on both cells, remove the ironn and let them snap into contact.

"The Natural Philosopher" > wrote

I make my own packs all of the time, but have never felt comfortable with direct cell to cell connecting.

I am afraid that if there is any load or vibration placed on the pack, the stress could make the joint fail, and then...

I like the way commercial packs are usually made with a connecting strip of metal, or in my case, I use a short length of wire, or more likely, a length of copper de-soldering braid. I solder them on with a little offset, so they nest beside each other when the pack is assembled.

My technique is to put a drop of self tinning paste flux on the cell and wire, and tin both. Then, I cool the cell with a wet rag, dry it, and apply the heat to the wire and get it pretty hot with an extra drop of solder ( non resin core lead and 2% silver containing solder) on the wire. I then place the wire and iron to the tinned cell, and as soon as it flows, remove the heat (holding it still until it solidifies to avoid a cold joint) then quickly cool the cell again.

I haven't had one fail yet, or do damage to the cell. (knock on wood )

I have an 8 pack of NIMH 2/3 aa's that I have correctly soldered wit

the connector. Although each cell shows a good reading, I can't get reading on the total pack and of course, I can't charge it. I hav checked all battery bars repeatedly and have soldered and resoldere every connection! I need help from someone on this forum as to wha could be wrong Very frustrating

-- rccar

----------------------------------------------------------------------- rccary's Profile:

Start at one end with a probe on e.g the negative pole of the connector, and work your way up each intercell connection.

At some stage the reading will drop to zero.

The last connection you probed is bad.

If you get all the way to the top cell and nothing on the connector, the connector is bad.

Thanks, I found the bad connection.Soldering batteries is not as easy a

it looks

-- rccar

----------------------------------------------------------------------- rccary's Profile:

Never a truer word spoked..

;-)