Ijust noticed that my 4.5 V 600 mAh Rx pack is not enough for my plane, I'm thinkin on get 5 1200 mAh cells and make my own Rx pack, but my question is, will Ineed to get another charger? the one that Ihave is the stock charger that came with my Futaba radio and states it is for 4.5 V 1000 mAh packs, it also states that it must be only used with that kind of batteries or there could be a fire danger... the rx pack that came with the radio is actuallythe 600 mAh and Ihave never had any problem, can Istill use this charger with a 6.0 V 1200 mAh pack?

It will easily work if you went to a 4-cell 1200MAh pack - it would just take twice as long to charge.

Some people say that it is ok to charge a 6-cell pack with them, but I prefer not to.

couple of things the wall wart charger will take forever to charge the batterys your talking about, and may not charge 6V batterys at all, your better off getting a quality charger.

making battery packs can be tricky, these days you can pick up a Nicad or NiMh battery with huge capacity for cheap on ebay,or from www.cheapbatterypacks.com I just bought 4 NiMh 4.8V 2500's for 30$ off ebay, well worth not having to hassle with making them http://cgi.ebay.com/ws/eBayISAPI.dll...=STRK:MEWAX:IT .

the same seller has 6V as well if thats what you want its up to you

will it take twice to charge even when the charger says it is for a 1000 mAh pack?  ,

I agree with bigtim. soldering battery cells together is a very critical task and uless it's done properly you could easily ruin a cell. unless you are very good at soldering you might want to consider buying prebuilt packs. The seal on a battery cell is very thin plastic and if you heat it too long it will melt the seal and the battery will be ruined. And what is too long?? 2 secs is really too long. Once that seal is ruined the cell is no good. While it may look like it will hold a charge after the seal is shot, it's a false reading as the battery can fail at any time now. With the low cost of packs now it's easier to simply buy a pack already built.

Ken</p>

What is important is the output in MAh. If it's 50MAh, it will take 12 hours to charge a 600MAh pack and 24 hours to charge a 1200MAh pack

understood, I guess it don't worth it to make my own pack if the difference in the price isn't that big.

have problem of my rx batteris low on charge. new and old finaly purchased new volt checker, now bad batteries are fully charged according to it never heard of checker going bad

Chocorrol,
Remember, a 5 cell pack has a higher current drain than a 4 cell pack.
Going from a 4 cell 600 to a 5 cell 1200 will NOT double your flying time.
Going from a 4 cell 600 to a 4 cell 1200 will double your flying time.
Good Luck,
KW_Counter

Hi!
But why use 1200mAh batteries when there are 2800mAh cells the same size (AA,R6)???
I have charged my 2200 and 2600mAh NiMH cells for years using my JR 50mAh wall chargers and it just works perfect. Just charge 24-30 hours...what's the problem with that ???
4,8-6V works equally well!

Soldering together a pack from individual batteries cells is easy! Just sand the battery plates and put some soldering acid on...then tin the end plates and then... quickly solder the presoldered cables to the end plates . This takes just one second with a good soldering iron (Weller 50W).

Pictures below shows GP:s 850mAh NiMH "High current" AA cells without soldering tabs (which aren't necessary). These cells are first Ca glued together and then wires are soldered on.

Well, I know that personally, I rarely get to charge any longer than overnight, so I like a pack that can be fully charged in 8 - 12 hrs

I always go out to the field with a load meter to test my batteries under load conditions and a 12V quick charger. Even with the QC I generally charge under 1 c, but I can charge at the field if I need to.

so then, other than the charging time, there won't be any trouble? let's say that Igo to a good electronic workshop to soldering the cells together, cause I'm not that good to do that kind of jobs...

Soldering is not something that you just do. There is a technique that you learn by doing it over and over again with someone watching. If the flow is not correct, the bond is non existent. If you leave the iron on the battery to long, you will burn through the membrane that Ken was talking about. Each battery has two ends, a positive end and a negative end. That gives you two chances of damaging the battery if you do not do it correctly.

If you DO decide to solder your own packs, then go to a site like RadicalRC.COM and get batteries with the solder tabs already tacked on. This way, you solder to the tabs and not to the battery ends.

But, as a few of us have already suggested, just get the packs already made up. This way you have a good pack that has cells that have been soldered by pro's.

CGr.

You shouldn't run soldered packs in airplanes anyway. The vibration can break down the solder joint causing it to fail. A quality pack will have the cells welded so that doesn't happen. It'll also use good cells, which basically means Sanyos. Take a look at www.hangtimehobbies.com for some quality packs. I'm a satisfied customer and can attest that they sell a reliable product.

if you know how to solder they shouldnt fail...period
as for soldering your own packs dont bother...unless you already have the batteries
just buy them from here,
http://www.all-battery.com/60vrcairbatteries.aspx
http://www.all-battery.com/48vairplanebatterypacks.aspx
i literally have hundreds of their cells and all have worked great. some over 3 years old and been put through hell and still going strong

I ordered from allbattery twice,,, and I will never do it again. I got burned both times with bad batteries. Im replacing those bad packs with some from cheapbatterypacks.com.... hope thatll do the trick.

Agreed Jimmyjames, they shouldn't fail. And they probably won't. But a soft solder joint is so much weaker than a weld and so much easier to get wrong and not know it, and figuring there's 10 of them in a 4.8 pack, the chances for one of them failing are far higher. Other guys can do what they want to, but for me it's all welded packs with Sanyo cells. Buying from hangtime, I can't save $10 per airplane buy going the cheapo route on Nicd's. For $10, I'll buy the best and not have to worry about them.

Hi!
I take pride in knowing how to solder! Done this for 35 years!
How can you be a model flier without knowing how to solder...??? Beats me!

Practice makes perfect,ive been soldering for a few years,but i buy battery packs pre-made ,just cause of the hassle of doing them yourself,But this is a hobby and it is nice when you Do/Make/Build something on you own,i have repaired a few 4.8V's that i use for my Super Cub,the tabs were already on the battery and its alot easier.

PS you learn from your mistakes lol

I routinely solder on very very small and delicate traces. Needless to say, I'm quite good. I still buy premade packs just because it isn't worth the hassle.

I have tried to teach some of my students how to solder, everything from Deans connectors to adding servo wire to lengthen instead of using extensions. For the most part soldering is a lost art. When I was in Jr. High School it was taught to all boys in electric shop at the age of 13, all boys had to take every shop offered back then so tools weren't a mystery. Today driving a car with a standard trans. is a mystery to most people. Last year I bought a pile of Eneloop batteries for next to nothing. Instead of soldering them up like Jan does I went into radio shack and bought a few different types of those cool little battery holders with the wires already there. I only had to solder on the plugs. They work great and cost almost nothing. I still use one of my old ACE chargers that charges 6 batteries at a time and I can set the mah, the charger doesn't know if it's 6 volts or 4.8 but it only goes up to 1500mah. If the pack is bigger then that I top them up at the field with my quick charger. Just an FYI, not for everyone but it works for me.

I also have been soldering for to many years to count. I have found that the biggest error made by many who say they can not solder is that they are either using to small (to low a wattage ) iron or not having the items to be soldered clean. Use of the proper flux is also a big aid in getting a neat joint. Depending on the mass of the item being soldered, the size of you soldering iron tip is also important, for larger items such as a Deans connector, you need a fairly large (large mass for heat retention) tip.

I have been soldering packs for many years and have had very good success. I solder using only batteries with tabs and I use a soldering station which I can control the temperature. It cost me about $8 to make a 4 cell 2200 mah pack. This includes the connector and shrink wrap.

Gene:

One problem that has come up in recent years is the switch from 60-40 solder to that crap that we are forced into using now that does not contain any lead. It requires a specific temperature to work, and the flow is terrible as compared to what it used to be.

I have a roll of real fine 60-40 solder that is rosin-core and is like gold. I keep it in my safe.. just kidding.. but if my house was ever robbed, I'd immediately check to see if they took my 60-40 rosin-core solder!!! [:@]

But, you are correct. It is a lost art. And, as I said, using this new junk turns a skill into a chore.

CGr.