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huse0054
04-14-2011, 11:08 PM
Hi all, new to the forum and to FE. I recently purchased a Geico and have ran it a couple times stock on 2 7.4v NIMH 3300's. Don't laugh but this thing is fast and fun!!!

The only other boat I have used was an old Villian IV.

I have spent many nights reading this forum and the information is fantastic, I thank you all!!!!

My questions:
1. Will 2, 4s 5000mah lipo's wired in parallel give you double the run time as 2, 2s 5000mah lipo's wired in series?

Thanks

LiPo Power
04-14-2011, 11:39 PM
Yeah, that is total of 10000mAh so double of the run time.... Make sure not to wire them in series!!! It will be heavier....
How are you planning to put 2 4S lipos without modyfying the wooden part of geico? Will they fit?

huse0054
04-14-2011, 11:53 PM
Good question but have not gotten that far, was more seeing if my understanding of how lipo's operate in series vs parallel is correct.

Good question though and I have no idea if they would fit. Are the 4s batteries twice as thick as the 2s?

Other than the larger size (and assuming they would fit) why wouldn't a person run the 4s in parallel over 2s in series?

Maybe I am missing something but wouldn't longer run times be preferred?

LiPo Power
04-15-2011, 12:01 AM
Weight..... is the issue.... Size... is the issue many times... Temps are the issue if run too long...
And yes, they are twice the thickness....

jac4412
04-15-2011, 12:04 AM
Huse... do we want longer runtimes? Yes absolutely. The problem is what happens...

Boat systems specifically tend to have alot of "work" done to them. That is, a lot of forces are generated and are in play. The heart of the system, the ESC is what you need to worry about. Simply put... the harder and longer you run... the more "work" is done on the system.

What I mean by work is the current flowing through the wires (resistance there), amp draw from the boat... waves... acceleration... deceleration.... any sort of resistance... the water itself... etc... All of these variables contribute to the speed of the boat and the amount of heat generated. Heat is the killer of boats and ESCs. We try to eliminate as much heat buildup as possible.. through water cooling and making an optimal setup. Less heat= longer esc life. However.... no matter what we do of course.. there will always be heat. The longer you run your boat, the more variables influence your ESC overtime. Your best bet is to play it safe, get a good setup and maintain a stable runtime. What I mean by this is, even though my MG can get a solid 8-10 mins if I pushed her and took of the LVC, I typically run her only for 4-5 mins. I get a good run out and I make sure that the ESC get's a break... it'll help keep it last. I'm not saying that youre going to blow ESCs left and right or even if you see a significant effect but the safe bet is always to keep the runtime at a safe level. Also, typically the more speed, the less runtime.

As for your battery questions... depends on which ones youre looking at really (different batt companies make different sizes).

I hope I answered your question... simply put ya I wanna run my boat for a half an hour... doesn't mean I should!

huse0054
04-15-2011, 12:30 AM
Thanks for the responses, much clearer now.....If only life had no trade offs!

The other thing I was thinking about "upgrading" on the miss geico was the hatch, per many posts on here. I have two ideas and wondering what peoples thoughts would be on the following.

-To completely make the inside waterproof by adding fiberglass or carbon fiber to the Tupperware lid and adding 4 reinforcement points that latched or screwed into standoffs inside the hull. I would then add a seal or gasket so the screws would tighten down the the Tupperware lid, compressing the seal or gasket to the hull. (Why? because I like modifying and trying to improve things, and because I can)

-Then carbon fiber or fiberglass the inside of the external hatch to reinforce that as many people have said it cracks easily.

1. So my question would be is it possible to get the fiberglass/epoxy to stick to both the inside tupperware cover and external plastic cover.

2. Does anyone know a good place to learn more about how to fiberglass/carbon fiber?

jac4412
04-15-2011, 10:40 AM
To answer those questions...

1- Yes... just all in a matter of playing around with your combinations anddd
2- Here... there are several people here who are pretty knowledgeable with fiberglass and cfiber... I would suggest posting in the general section asking about it (you can also do a search, there are plenty of topics on it) and someone with more experience will speak up

jac4412
04-15-2011, 10:44 AM
Also keep in mind if youre going to play around with fiberglass/epoxy what I meant by "play around" is that since the plastic isn't naturally able to soak up the glue you'll have to figure out a way to do so. Can it be done.... absolutely. But with some more modification

JPriami
04-15-2011, 11:05 AM
I'm glassing mine later today. I taped off the windsheild and the sanded the underside of the lid everywhere with a scotch brite. Then used a rough grit paper to make some nice deep grooves for the epoxy resin to grab ahold of then lightly back over with scotch brite. Then used a little rag with some lacquer thiner to clean it from the sanding dust. I'll post pics in my other thread when done.

TheShaughnessy
04-16-2011, 12:32 PM
i run 4s 2p in my MG all day, i prefer it over the 1 p set up, If i was running SAW I would run 1p but other then that i like the extra weight. My 4s turnigy packs have about 1/4 inch of play, they are a tight fit but they do fit. You can see how BJ modded his trays to make the battery fit a snap.

huse0054
04-16-2011, 06:46 PM
Thanks TheShaughnessy,

I may have to pick up a couple of each and give them a shot!