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[Anchorboy46]

O.K. Jus wanted to see the condition of my Graupner 8.4 volt motors, I hooked up a 7.2 volt battery to each motor and checked them out after greasing the 2 to 1 gear reductions with petrol jelly, I contacted the battery to each motor individually. The motors took off beautifully. The shafts were spinning as was the props! I had to lube the shaft tubes to get maximum shaft RPM.
 Question: What batteries are best, and do you hook up the motor battery together with the R/C battery pack or are they separate with two stations?  Anchorboy

[malcolmfrary]

Question: What batteries are best, and do you hook up the motor battery together with the R/C battery pack or are they separate with two stations?  Anchorboy

What batteries are best?  How long is an elastic band?  Questions with a similar basis.
The best batteries are the ones that fit the boat and do the job.  In the case of batteries its a balance of run time required, cost, weight carrying ability and probably what is available.  In the case of the elastoc band, how big was it before it got stretched, and how hard did you pull it? 
If the battery is moderately above 4.8 volts that the RC wants to see, most of us go for the BEC included in many ESCs.  If 6 volts, just hook it up, the RC is designed for 6 volts.  There comes a point where the BEC cannot handle the volt drop at the current demanded, and a separate RC battery is a good idea.  Some folks just dont like BECs, thinking them an infernal invention, but this is a personal choice.

[FullLeatherJacket]

If 6 volts, just hook it up, the RC is designed for 6 volts.  

Be careful here. A fully-charged 6v SLA or NiMH pack can top out at 7.5volts, which is enough to fry the microprocessors fitted into some receivers and speed controllers. If you're not sure then either check with the manufacturer or stick with a 4-cell pack (or 5v BEC) to power the receiver.

FLJ

[malcolmfrary]

Fair enough - I wasn't being modern.  RC, pretty much since transistors became the norm, were designed around a nominal 6 volt "standard" because it was useful - either three lead-acid cells, four dry cells or five nicads.  Four NiCads gives a nominal 4.8, which is within operational limits for nominal 6v equipment (usually) and has become very common because four cell holders are really easy to come by for RX packs, and happens to be "near enough" for 5 volts, for which regulators are very readily available from the computer parts trade.
Hopefully manufacturers will have great big idiot-proofing on the packet saying "DO NOT USE WITH 6 VOLT SLA BATTERIES".  Having said that, I would probably be the one to prove it, only reading that bit later on.

[FullLeatherJacket]

Hopefully manufacturers will have great big idiot-proofing on the packet saying "DO NOT USE WITH 6 VOLT SLA BATTERIES".  Having said that, I would probably be the one to prove it, only reading that bit later on.

Only very recently, Doc - and someone else on the Forum beat you to it! Mind, if I called him a big idiot then I'd really be for it................
I suspect he'll be bringing the thus-wounded unit to the Doncaster show for a bit of FLJ TLC.

FLJ

[Anchorboy46]

O.K. question. What does BECs stand for? What does ESC stand for? Forgive me I'm from Texas! I don't get the smart remark about the rubberband other than you were trying to make a point that my question was too vague? I was trying to find out what brand of cell is most favorite to use and do you use two battery stations, one being for radio and one being for propulsion.Or do you use the same battery for both...? Anchorboy

[Shipmate60]

ESC - Electronic Speed Controller

BEC - Battery Elimination Circuit, it allows you to power the receiver from the main drive battery.

Bob

[portside II]

B.E.C. battery elliminator circut
E.S.C. electronic speed controler
with a E.S.C that has a built in B.E.C. you dont need a seperate battery ,
but you do need to observe the maximum imput voltage , ie dont put 24v into a E.S.C. with a max of 12v .
As for the type of battery , that depends on what your craft is , you dont want to be using a 12v 20ah gel cell in a speed boat, likewise you dont realy want to use a 6v AAA pack for a large tug , horses for courses.
daz
morning Bob!

[malcolmfrary]

Hi Anchorboy, sorry about the English sense of humour.  Not having anything in the "location" field, I assumed you were over here.
If looking for a good battery in the US, have a look in a US site like RCgroups.  They are a helpful lot there, and importantly, with their local knowledge will be able to give you good advice on what is available your side of the pond.  Shipping a battery overseas can be expensive.

[Roger in France]

This is a good example of why it helps to show your location.

Go on folk, make an addition to your "Mayhem Profile", you know it makes sense!

Roger in France
Moderator

[portside II]

Yeh  come on Dave , show us where you live 
It cant be that bad.
daz