Making my own packs tips and tricks
02-28-2006, 12:15 PM
#1
Senior Member
Thread Starter
Making my own packs tips and tricks
Hey guys. I have been building my own RX packs for 3 years now. I thought I would share my building process in case anybody wlse wants to try a hand at it. I have built probably 15 packs, and have NEVER had a failure.
I use NiMH exclusively, and build mostly AA 4 cell packs. I have built a C sized 5 cell pack for use on my giant scale.
1) Go to Walmart and buy the largest capacity NimH Energizer packs you can find. You can usually get 8 for $10, enough for 2 packs. The last ones I bought were 2500 ma.
2) keep the packs together in their respective boxes, ie mark each set of four so you have the same cells in the box going for the same pack.
3) Take some 200 grit sandpaper and scuff both negative and positive sides. Wipe with alcohol.
4) Layout you cells like the pack will look, and hot glue the cells together.
5) Using a rubber jawed vise, gently clamp the pack in place so you can work on one side at a time.
6) Go to the auto parts store and ask for the smallest gauge braided ground wire they have. I get 8 inches for about 2 bucks, enough for 5 or 6 packs. I soak the braid in solder, and if it is too wide, snip it in half length-wise.
7) cut the braid to fit between you cells.
8) With a qtip, dab a small amount of solder paste on each cells contact area. Tin the cells with as little amount of solder you can muster.
9) Using a solder GUN (Iron's don't get hot enough to melt the solder without heating the battery) apply heat to the braid, until it melts in with the tinning on the cell.
10) Repeat for all connections.
11) Use a cheap 24" inch servo extionsion for the connector. I like the 24s, as i can make a long lead if I need too, or snip it half and use 12" for the pack, and keep the other end for a charge jack spare.
12) Heat shrink wrap the pack in regular heat shrink, or a thick rubber heat shrink.
13) all done. You could test the joints on your pack by gently prying at it with a small screwdriver. I reccomend doing this if you are a newbie. The prying action will let you know if you have a cold joint.
I can build a 2500 Ma pack for $10. Sure beats paying $30 for a pack with less Ma, and is easy. I can build two packs in less than half an hour.
I use NiMH exclusively, and build mostly AA 4 cell packs. I have built a C sized 5 cell pack for use on my giant scale.
1) Go to Walmart and buy the largest capacity NimH Energizer packs you can find. You can usually get 8 for $10, enough for 2 packs. The last ones I bought were 2500 ma.
2) keep the packs together in their respective boxes, ie mark each set of four so you have the same cells in the box going for the same pack.
3) Take some 200 grit sandpaper and scuff both negative and positive sides. Wipe with alcohol.
4) Layout you cells like the pack will look, and hot glue the cells together.
5) Using a rubber jawed vise, gently clamp the pack in place so you can work on one side at a time.
6) Go to the auto parts store and ask for the smallest gauge braided ground wire they have. I get 8 inches for about 2 bucks, enough for 5 or 6 packs. I soak the braid in solder, and if it is too wide, snip it in half length-wise.
7) cut the braid to fit between you cells.
8) With a qtip, dab a small amount of solder paste on each cells contact area. Tin the cells with as little amount of solder you can muster.
9) Using a solder GUN (Iron's don't get hot enough to melt the solder without heating the battery) apply heat to the braid, until it melts in with the tinning on the cell.
10) Repeat for all connections.
11) Use a cheap 24" inch servo extionsion for the connector. I like the 24s, as i can make a long lead if I need too, or snip it half and use 12" for the pack, and keep the other end for a charge jack spare.
12) Heat shrink wrap the pack in regular heat shrink, or a thick rubber heat shrink.
13) all done. You could test the joints on your pack by gently prying at it with a small screwdriver. I reccomend doing this if you are a newbie. The prying action will let you know if you have a cold joint.
I can build a 2500 Ma pack for $10. Sure beats paying $30 for a pack with less Ma, and is easy. I can build two packs in less than half an hour.
02-28-2006, 12:53 PM
#2
RE: Making my own packs tips and tricks
I buy welded packs. Just my choice. If you have an iron larger than 60 watts with the appropriate 1/4" chisel tip and keep it tinned it will work as well as a gun.
If you don't know how to solder save yourself some grief and buy welded packs. There is a nylon insulator under the positive button that if it melts destroys the seal that maintains the cells integrity. Nylon has its glass transition at 460°F - 500°F . Soldering is usually done in the 650 to 750°F range for 60 / 40 solder.
Just my two cents,
John
If you don't know how to solder save yourself some grief and buy welded packs. There is a nylon insulator under the positive button that if it melts destroys the seal that maintains the cells integrity. Nylon has its glass transition at 460°F - 500°F . Soldering is usually done in the 650 to 750°F range for 60 / 40 solder.
Just my two cents,
John
02-28-2006, 02:37 PM
#3
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RE: Making my own packs tips and tricks
ORIGINAL: JNorton
I buy welded packs. Just my choice. If you have an iron larger than 60 watts with the appropriate 1/4" chisel tip and keep it tinned it will work as well as a gun.
If you don't know how to solder save yourself some grief and buy welded packs. There is a nylon insulator under the positive button that if it melts destroys the seal that maintains the cells integrity. Nylon has its glass transition at 460°F - 500°F . Soldering is usually done in the 650 to 750°F range for 60 / 40 solder.
Just my two cents,
John
I buy welded packs. Just my choice. If you have an iron larger than 60 watts with the appropriate 1/4" chisel tip and keep it tinned it will work as well as a gun.
If you don't know how to solder save yourself some grief and buy welded packs. There is a nylon insulator under the positive button that if it melts destroys the seal that maintains the cells integrity. Nylon has its glass transition at 460°F - 500°F . Soldering is usually done in the 650 to 750°F range for 60 / 40 solder.
Just my two cents,
John
The difference between the way I do it, and the method above, is that I use copper battery bars, I use electrical tape and a bench vise to hold the cells together instead of hot glue and I use Deans connectors (ultra for sub-c packs, and micro for receiver packs) instead of receiver connectors.
But overall, I agree, it is alot cheaper to build your packs if you have the time.
EDIT: How did you make this -------> ° symbol? I copy and pasted yours, because I had been using an asterisk (*) to represent degrees.
