Constructing a battery pack

[MikeDahms]

I am wanting to construct a new battery pack for my 1980's JW Fishers pulse 8 machine. The pack is 5 C cell batteries that are wired together. The wire is soldered onto the batteries. I have attempted to do solder directly to batteries before but have been unable to make it work. I hope someone here has a way of doing this correctly. The detector has been in storage for many years so I know I need to replace the batteries and I need to keep the cost down. JW Fishers charges $75 for a battery pack. So any one who has experience or a place to look up the information please let me know. Thank you, Mike.

[cosmic]

Try rc hobby sites..

[MikeDahms]

Thank you I'll give it a try, Mike.

[khouse]

I'm not familiar with that detector but your sure it's 5 cells? You can find 6- C cell battery holders all over. You may have to buy one and alter the wiring for your application. But you can solder wires to batteries. First sand the area your going to attach your wire. Make sure there is no shinny surface left. Then make sure your iron is very hot. Use rosin core small diameter solder. Pre tin you battery area. This means lay a bed of solder on the battery. Then pre tin your wire. Then put both together and use your iron to remelt the two together.

[MikeDahms]

Let me say thank you to all who posted here and Jeffery who PMed me. I do have experience soldering but the couple of times I attempted to solder wires directly to a battery I failed. This time I wanted to get some help. Let me list the steps others have passed on to me.
1. roughen up the surface of the battery end with sand paper
2. apply flux to the roughened surface(you can use rosin core solder and not use the flux)
3. tin the area you just applied flux
4. flux then tin the end of the wire that is to be soldered to the battery
5. apply flux and solder the wire to the battery
6. clean all areas where flux was applied( flux is an acid)
Lastly the solder gun/torch much be hot enough to heat the end of the battery quickly that way the heat is applied for a short amount of time and in the end heats the entire battery very little. If you use a solder gun without sufficient power it takes too long to heat battery and can cause damage to the battery.
Lastly, a chain store called "batteries plus" offers to do soldering.
And to khouse, the detector is still in the attic but as I recall it is either 5 or 6 batteries arranged with one in the center and the others glued around it. The housing on this, an older pulse 8, is round which is why the battery pack is constructed this way.
Again thank you, Mike.

[Brett]

Mike,

I would definitely go the Batteries Plus route. I've worked with them many times in the past for quick jobs and they can get it done pretty good. Their spot welding machine will definitely be better than a cheap soldering iron that you'll have to buy (I'm assuming you don't have a good one). Depending on various things, you may be able to upgrade your technology and save some weight... try Sub-C NiMH batteries instead of standard C size. Batteries Plus should be able to get you some 3300mAh cells made by Gold Peak. They should be about $4 per cell and they should assemble it for you for free if you sweet talk 'em.

You're going to need a battery charger as well. Many low end r/c hobby chargers are programmable for the cell type and number of cells.

Good luck!

[MikeDahms]

Outstanding advice. That takes the cost from $75 down to about $20 and no shipping. What a deal. Thank you for the advice and I am finding out what a large selection is available at Batteries plus. Thanks and I really like the picture you have below your name, Mike.