Its the beginning of the sailing season here and I was looking over my boat from winter storage (the basement) and getting things put back together. When I flipped the switch Nothin but twitching… Yep the batteries are goners.
Just curious what everybody else out there is using and if they feel there is an advantage to one type verus another.
I currently have been using the rechargable Nihm batteries. They have lasted me one good summer. The charge seems to last about 4 hrs with one servo and a winch along with the ones in my attack controller.
I use now mostly only NiMH…dont have to think about re-charging them…I mean full or empty…I just dont care! and it works nice; they also have lots of mAh (varies from 2000mAh to 2300mAh for the new ones)…the only bad point they have…a bit heavier compared to NiCd…
I heard that we can now use some Kokam (lithium) batteries…but still way too expensive…I posted a thread about a new type of batteries…they are buy-able (at least overhere [;)]) but nothing yet we could use (size!) as for now…I keep looking!
<blockquote id=“quote”><font size=“1” face=“Verdana, Arial, Helvetica” id=“quote”>quote:<hr height=“1” noshade id=“quote”>the only bad point they have…a bit heavier compared to NiCd…
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Hey Wis, are you sure about this statement?
NiMh cells are about 30% lighter (capacity to weight ratio)
You can not compare weights of similar size cells without also comparing the capacity.
As for Chad’s question… If you are sailing a small boat (30"-36") AA sized NiMh cells are the best power to weight ratio. Remember you will need a proper charger for the NiMh cells.
Larger boats work very well with the Sub C sized 2400 NiCad or 3300 NiMh cells.
All of our demo boats have 5 cell packs in them. The higher voltage gives better servo speed and also increases run time as the current draw is lower on the higher voltage set up.
Good cells are very important. It amazes me how many people trust an expensive model to cheap $2.00 rechargeables from Wall Mart. Those cells do not put out their listed voltage or capacity. Face it, if your receiver pack craps out, it makes no difference how good the rest of your boat is.
Spend the money on good cells and a proper charger. They will last you many good years if you look after them.
Did you store your battery packs in a fully-charged state over the winter? If not, you’re SUNK ( a 4-letter word) I have tried different ways to revive some packs with no success. I tried freezing them before charging, cycling at high current, zapping…
Peter;
I am no pro with batteries, but it seems to me that the NiCd I used before jumping to NiMH are heavier…but, yup, the NiMH have much more mAh…so, I guess you are right.
I use AA batteries, made by Sanyo…
As for comparing NiCd and NiMH, I cant really do that!..I cant find NiCd having the same capacity as NiMH (with 4 cell)…sorry, you are right, and I am wrong! Next time, before talking crap, I ll ask the pro [;)]
do many use 6 cells? been using mine at 9 volts for a while and have plenty of power/stamina nothing burnt out yet(yet…). another upside of this is if your only out for a while you can pulg a single cell 9v batt to the system and half your weight. I have a 6cell pack with the 9v “clip terminals” on it so switching to single cell is quick and easy. Probably voids my warrinty which ran out anyway but working well so far.
The radio equipment was designed to work with 4.8 - 6.0 volt batteries. Since most systems use CMOS components, you could conceivably go up to 15.0 volts, but you never know for sure, unless you have the engineering data. That’s why the 9V battery will work, usually. I used a 7.2 volt pack before because I had some from r/c cars, but I have everything changed over to AA NIMH cells now, so I can use the same charging equipment for any pack.
lol are you kidding me
i dont paint a hull if i can save the oz of piant. but i dont race that competeive anymore
you need to keep in mind the conditions that you are sailing in. a light boat accelerates realy fast. less wieght to get up and going.
cougar
long live the cup
the point is that 1 oz in a 17 lb (288 ounces!) is less than 0.5%, which is nothing. I know there are people that claim it helps, but it doesn’t in that case. 7 lbs=112 oz
Take drag racing cars… Take take 0.1 sec off you ET, you need to remove 100 lbs. On a 2000 lb car, that’s 5%!
See? So you need to save an ounce in several ( at least) places to really make a difference.
Tom…you answered your own question.
Weight is inversely proportional to horsepower.
Your sails will produce a certain horsepower at any given windspeed. The less weight you have to push with that fixed horsepower, the faster your boat will accelerate.
It is not rocket science.
Most sailors can not sail a boat well enough to even appreciate a 10% difference in overall weight.
Since most of the models on the market today are far from optimum in design, that weight makes little to no difference to the “average Sunday” sailor.
For tight one design racing, the lightest, cleanest boat that is optimally set up for the conditions will always have an advantage over a heavier one.
I will go so far as to cut extra threads off of 4/40 bolts to save weight on my own boats.
Ask anyone who has sailied against me, or tried one of my boats, they will tell you it makes a difference when they are waiting at the finish line for the rest of the fleet to finish.
Does it make a difference? YES.
Does it make a difference to your boats or the way you sail them? Probably not.
0.1 sec in a 4.5 sec. car is 2.2%. That’s a lot. I think the America’s cup boats are looking for tenths of a percent. A 1000 foot long model race I would be beating you by 22’.