LOL. Ya I just woke up. NEED more coffee. Its still Frozen here. The boat is still floating in the tub. I Feel I Feel I Feel.....................THe Need. Help[:-]

Ice,
Definitely go with Deans or something comparable.

When someone wrote here is the battery thread.. I thought I am on it... Now I get the post from the other thread. This is the actual BATTERY thread... So about how many amps does this motor pull. Actually what is the name of it. I got conformation fromUPS the delivery is not coming till tomarrow... I am going nuts watching these videos, you guys have to stop... hahaha

It should be on average around 35 Amps or so. Of course it has a lot to do with prop and strut adjustments.

Ryan

what mah lipo should i get? i was looking at some 2200mah 4s 20-30c. would this work?

I am a little cautious with the NIMH batteries, first time messing with them. I got the new batterys yesterday, changed the connectors and charged one set on .9 amps for the first cycle. I discharged them using my light bar set up. Got 10 1/2 min out of the batterys and this was the first cylcle. The pack seemed to hold full power right to the end, so first impression the cells are matched pretty good. The pack only got mildly warm during discharge, which was a very good sign. I get 4 1/2 min with my dischage lights, out of the 1500 NiCD packs, 10 1/2 was real good on the first cycle for the new packs. I think I will cycle the new packs onece more then give them a try in the boat. The Tenergy 4500 mha 7 cell packs look real good to me so far, 14 guage wire.. Would have liked to see 12 but 14 will be fine.

Not sure if I cycled the batteerys exactly right, did a slow charge twice, discharged twice THEN.....hehehehe put the new Tenergy 7 cell 4500"s onto there smart chargers (got 2) on 1.8 amps. It took 1 hour 55 min. Now the important stuff... The boat is a totally sick rocket... How can I decribe it.. sick, totally insain, animal, unbelievable, I am absolutly SHOCKED. These batterys a seriously very good, excellnt. I ran that boat for at least 6 miniutes, brought it in to check everything. The batterys were luke warm, the speed control not even warm, the motor was more then warm but not hot. Same packs back in... at least 6 or 7 more miniutes of the exact punch I had when the run first started. The boat slowed all at once, the cells are definatly matched pretty good. The pack were warm, not in the least bit hot. The motor was to hot for me, I need to upgrade the cooling. I will say I like the stock prop. Almost wish I didnt order any others. I need adjustable trim tabs. Here is the deal I got....... they deserve the mention.

http://www.all-battery.com/index.asp...OD&ProdID=1685

http://www.all-battery.com/index.asp...OD&ProdID=1681

what speed contoller, cause i doubt the stock will work for a lehner motor upgrade w/ 3 or maybe 4s lipo setup????
any ideas?

look at the hacker and phoenix controls.

i decided to go with 2 7-cell ib3800. it only costs me 45.50 total w/o shippping

hextronic has cheap 120 amp escs for 52.00 on united hobbies i believe. dont know how good they are tho.

I'm looking at cheapbatterypacks.com. Is it worth it for 12 buck a pack to go from the 3600 to the 4500 elites. If I do the bar upgrade and have them make the packs they'll be 50 bucks each. Does this sound right? I wanna go fast. [>:]

Hi sv27dayton, check out http://www.spcracing.com/ I bought the matched twin maxx pacs and they are IB4200 just a suggestion and they are great to deal with if you have any questions or problems.

Ken

Thanks Ken. I'll consider that too.

I actually read through the entire thread and a couple of things jumped out.

SubC 6 cell NiMh generate a lot of heat but mostly when they lose power at the end of the run. Given this what recommendations are made for time/mAh rating and running to shore (fast of slow)?

The SV27 ESC is rated for 45 Amps and one post showed 65 Amps on his wattmeter using Elite4500 cells. The excess will blow a couple of FETS, fry the ESC, thermal shutdown, or worse the "China Syndrome". What is recommended to keep the amp draw to what is rated for the ESC? Oh really? Going slower is NOT an option?

I guess based on my cheapo batteries frying, I will be going back to stock recommendation of DTXC2162 3800mAh 7.2 volt flat pack with Deans Ultra plug until I sort this out.

I'm not a nubee having uesd these 6 cell packs on the cheap EP racing boats with dual 380 sized brushed motors. The batteries get hot also but the motors go bad before the batteries do. I have the Astroflight 110D, MRC superbrain 959, Orbit Microlader. Triton, and two FMA Cellpros 4S. All are excellent chargers. I can charge any chemistry. I have a lot of LiPos but mostly parkflyer types 2000mAh 3S size and smaller. If you have a good charger and are careful you won't have any trouble with LiPo charging. That said, I would not trust the MRC Superbrain for LiPo charging. Too much bad stuff reported on that other site we are not allowed to talk about.

A123 or M1 LiOn chemistry is probably the way to go for boats. For your money you get a lot more amps, duration, longivity, fast charge, etc. Now if we can get a switchable voltage regulater for less than the $70.00 delta on the A123 racing site. I have read on that "other" site about tubes with tabs you can insert the cells into to configure what you want.

Enough for now, good thread. Now I'm not one of those three letter acronyms you all are throwing around, but having retired from a lifetime of mainframe computers see if you can guess what my favorite programming command is telling the computer: "DWIT"?

My grandson's latest joke: How do you keep a turkey in suspense?

I have attached a pic of my battery bunker. Yes it is an Army tank piston. Boy does that bring back memories. I can't believe my wife let me put it on the coffee table when we both smoked many years ago.

Nostick,

I am new to this boat so there is a lerning curve for me in the boat but one thing I can tell you is I never run my packs out in the car/boat/plane. I made a light discharger years ago. Not positive of actual amps it pulls but what I do it measure how long the batterys keep that light bright as when it started, when I feel it starts to fade I consider that time to stop the run. Like I got 2 sets of 7 cell 4500 Tenergy packs, they last 10 1/2 min on my bulb discharger, the light looses it full brilliance about 10 min, so what I am saying is you have to guage how long to stop beating up the pack, if you know what I mean. These new 7 cell 4500 Tenergys are fine, I have no heating issues. When the new 4500's come out in 6 cell packs I will pick up them and see how they do. Worst case senerio, I pull the pack apart and redo it side by side because the cells themselves are good, the way there assembled might need help.

SVDayton.
Sorry about that......I missed the post from the 16th. I would recommend going with the IB4200s. But don't waste the extra $$ on buying matched cells. Ryan, pretty knowledgeable about this stuff, recommended a while back that after a handful or two of runs, they won't be matched anymore. Balancing/form charging once a month will get them back a little, but that's as far as keeping them balanced will go.
If you can't get the IB4200s, then go with the 4500s. I run the ELITE4500s and they take quite alot of abuse, even when I run my largest prop (CF48).

No Stick,
If you run too wet, you will pull more, so try some different setups.......add positive trim tab. If you're running a 45 size prop, you shouldn't have a heat prob with the packs, or motor for that fact. Of course, cheap packs will get eaten alive with this boat.

I do know the MRC series before the 977 had bad probs charging the lipos, but OC has had excellent results with his 977. I also use this too, but haven't had my helis in the air yet this yr.

It might be wise to hold off on A123s until Wazool can get some test runs in. I haven't heard of any others using this in the SV setup.

Ice,
You really don't have to run NiMh cells through a discharger. In fact, it is heavily recommended not to, especially with a light bar. When first forming new packs and maybe periodically/seasonally to check the status of the packs; if you're charger can discharge too.

A good rule for when to bring the boat back in from hull smackin' is:
1. Never run the packs all the way down.....it'll ruin them (heat).
2. I do a few vic laps when the punch starts to fade. If you're not getting a decent rooster, bring her in. It's boring.

Hi all. I just reviewed information about MEC Solderless Power Tubes for subc and a123 cells. web site is here:

http://www.modelelectronicscorp.com/...SPTs/packs.php

Have you any experience with these power tubes?

Looks like a nice system for those of us without pack building skills. Easy to swap out a bad cell and rebuild off the shelf packs built with substandard bars.

I wasnt isinuating discharging your NiMH cells. I was just saying get a feel for when they quit or loose there punch then let up on them. I use the light bar to just test there times to see if they stay consistant over time. I do use the bar to drain the NiCD almost to total discharge then use a resistor till the resistor is cool. Had Sanyo packs a long time and there still perfect, they just dont last to long there only 1500's

Sounds cool. Just looking out. Watch the voltage drop at the end; but sounds like you know what you're doing.

Melted another set of Tenergy packs today but I'm getting better. Never had to use the tennis ball this time. Timer on my DX-7 is set for 4 minutes. Got out my NiMh instrurction sheet from Dave Thacker of Radical RC. I forgot all that stuff when I went to LiPo 3 years age. Dave says first charge is C/10. I bought a Hobbico Multicharger several years ago that slow charges up to four batteries using switchable rates between 10-500 mA. His calculation is C x 1.4 divided by charge mA = charge hours and the actual charge rate cannot be higher than 1/10C. For example, I am charging a 3000 mAh 6 cell NiMh at 250 mA (1/10C would be 300 mA) on a timer for 17 hours. Calculation is 3000 X 1.4 = 4200 divided by 250 mA = 16.8 hours. If the charging hours turns out to be less than 14 hours, the charge rate will be too high and if left unattneded on a non-peaking charger overheating will result. Over 14 hours will not cause overheaing. The result of slow charging is to fill up you pack up and all cells should theoretically be balanced as far as voltage is concerned. At this point you can now fast charge your packs. I actually used an automatic timer that turned the charger off after 17 hours.

I believe my cells were out of balance and the low voltage cells overheated under load.

This may fit the super tune thread but it has to do with batts so here it is. Not a big deal but I ejected some batteries last week in an "incident" and think I have a good cheap solution. I stopped at the LHS and picked up a piece of balsa approx 2.5x24x1/8. As luck wood have it the width was perfect for the SV's existing battery trays. I cut them to legnth and then cut some reliefs in them so the straps would not interefere with how they rested in the hull. I then epoxied one side and let dry. Then I did the other side and set them in the boat with the straps in place. I think they are going to be pretty solid.

That's a great idea. I came real close to doing the same thing, but the foam blocks I was telling you about is so much easier to install and remove during battery swaps and they weigh in at next to nothing. On the other hand, I did use 1/16 plywood in the floor of the Mean Machine to mount the batts to.

Local bowtie dealership said they didn't know where to look for them and then tried to sell me a new Tahoe. Could have been way more expencive than you let on!