Batteries for a new stock Pro Boat "Blackjack 29"

[Tom899]

I have a "Blackjack 29" ordered since I couldn't find a "Mystic" RTR in stock anyplace. Keep in mind this is my first boat. I'm not new to RC, but have been out of it for 15 years. It looks like the Dean connectors have been replaced with EC3. If I'm reading this right it looks like they are recommending 2s or 3s batteries. Here are some quotes from the specs.
•Water-cooled Dynamite marine 80 Amp ESC (6S compatible) and 1500kv brushless motor
•Dual Li-Po or Ni-MH operation
•Required to Run - (2) 2S-3S Li-Po batteries or (2) 7.2V - 8.4V Ni-MH batteries with EC3 connector
My question - Should I buy 2s or 3s batteries? I naturally would like speed but for my style of running on a coarse with pylons longevity will be very important. What batteries should I buy?
Thanks,
Tom

[G-UNIT]

Why not get x2 2s and x2 3s, that way you can run 4s or 5s or 6s your choice, just a thought.

[Fluid]

You have some incorrect data there, the ProBoat site has two different motors specified for the BJ29. :olleyes: The Blackjack actually has the Dynamite Marine 1800Kv Water-Cooled Brushless Motor. That motor is really not suitable for 6S, you will burn up your ESC if you are not very careful. 5S is as hot as I would go with that motor and ESC, but really that motor and 4S will give plenty of speed and will spin a bigger prop for better acceleration. I'd get a pair of 2S/5000 mAh packs with a minimum 35C rating. Remember that all the power in any FE boat is in the packs, not the motor or ESC.






.

[Tom899]

Why not get x2 2s and x2 3s, that way you can run 4s or 5s or 6s your choice, just a thought.
Thanks for the suggestions.

[Tom899]

You have some incorrect data there, the ProBoat site has two different motors specified for the BJ29. :olleyes: The Blackjack actually has the Dynamite Marine 1800Kv Water-Cooled Brushless Motor. That motor is really not suitable for 6S, you will burn up your ESC if you are not very careful. 5S is as hot as I would go with that motor and ESC, but really that motor and 4S will give plenty of speed and will spin a bigger prop for better acceleration. I'd get a pair of 2S/5000 mAh packs with a minimum 35C rating. Remember that all the power in any FE boat is in the packs, not the motor or ESC.






.

Thanks for the reply. Sorry about the incorrect data, I did a direct copy and paste from the Pro Boat web page. So we really don't know yet what it will have?

[EdW.]

I also ordered a Blackjack 29 and have been looking at battery possibilities. The batteries are in series, so 2 - 2S batteries achieve the 4S rating, etc. G-Units recommendation of having 2 - 2S and 2 - 3S with the same C rating and mah rating sounds pretty good to allow trying different options.

I have noted various comments, including Fluids, about the dangers of running 6S with the 1800 kv motor and 80a ESC, if your not careful! I guess I don't totally understand the possible problems, in that the system as installed appears to be rated for 6S, per ProBoat. Any help out there??

Also, if running the 5S setup, would the difference in Lipo weight be enough to throw off the balance of the boat? I believe it is about 160 grams difference. I know with my micro indoor flyers, grams are king!!!

Also, any later word on when the Blackjacks are due to ship??

Thanks,

EdW.

[Tom899]

Thanks for the information. I didn't realize the battery configuration is wired in series, is that all Pro Boats?. I was all set to for sure just get 3s, but now I may re think and get 2s?

I'm still trying to find out what the largest dimension battery works well, there are so many different sizes, maybe it's a non-issue?

My local hobby shop says around August 20th.

Thanks,
Tom


I also ordered a Blackjack 29 and have been looking at battery possibilities. The batteries are in series, so 2 - 2S batteries achieve the 4S rating, etc. G-Units recommendation of having 2 - 2S and 2 - 3S with the same C rating and mah rating sounds pretty good to allow trying different options.

I have noted various comments, including Fluids, about the dangers of running 6S with the 1800 kv motor and 80a ESC, if your not careful! I guess I don't totally understand the possible problems, in that the system as installed appears to be rated for 6S, per ProBoat. Any help out there??

Also, if running the 5S setup, would the difference in Lipo weight be enough to throw off the balance of the boat? I believe it is about 160 grams difference. I know with my micro indoor flyers, grams are king!!!

Also, any later word on when the Blackjacks are due to ship??

Thanks,

EdW.

[EdW.]

Sounds like we're on this "journey" together. I queried Horizon about the series vs. parallel wiring of the batteries. As I understand it, all Proboats that utilize 2 batteries are wired in series. Thus the voltage of each battery is added. If wired in parallel, the mah rating is added together which gives much longer run times, but the voltage isn't doubled . Thus, the 2 2S lipo batteries are 7.4v ea x 2 in series = 14.8v to the ESC / motor. In parallel, the two batteries would still only provide 7.4v to the ESC / motor. You would have to buy a 4S single battery to achieve the required 14.8v. And, from what I can tell, the boats are set up for the 2 battery configuration, so installation of a single battery would be problematic. Also, if you were to wire two 4S batteries in parallel, the weight difference would be huge, although it apparently might run "forever". Then there is the cost of 4S vs. 2S. I have seen alot of commentary on the Gen Ace Lipo batteries (http://www.hobbypartz.com/gens.html) as being very reasonable and preforming quite well. I probably will go with the 2 - 2S and 2-3S batteries to start with, and try out the variations as I go. I understand that it is very important to make sure the C rating and the mah rating on all the batteries is the same.

Let's keep in touch as we travel this new phase of our RC experience together.

EdW.

[stadiumyamaha]

I like running parallel on everything. It give you better run times, lowers amp draw, increases speeds and keeps heat down.
Check out the sky lipos as well. The 4s 4000 or 4400 mah batts fit great in that hull and a little extra weight is not always a bad thing in it. Jmo.

[EdW.]

Now that just made things really interesting. It appears you geico w/ 1800kv set up is similar to what the stock blackjack will be. Good to know about the advantages of parallel, especially the lower amp draw, which must help keep the ESC cooler, etc.

What other mods are you running on the geico? Also, I am seeing alot of talk about props, etc. Guess I need a "newbie course" on props and how size and pitch relate to speed, amp draw, etc. etc. Thanks for jumping in on this discussion. Any and all info, recommendations are welcome.

EdW.

[Tom899]

EdW,

Yes, sounds like we are learning about these batteries and what might work best. Now we are really confused thinking whether we should switch the stock wiring from series to parallel. This definitely makes a difference on what battery configuration to buy? After a few weeks of reading about battery chargers and power supplies I ended up with a FMA PowerLab 6 and a couple of (JRPLANE)12v PS in series to make a 24v 47amp setup.

Tom


Sounds like we're on this "journey" together. I queried Horizon about the series vs. parallel wiring of the batteries. As I understand it, all Proboats that utilize 2 batteries are wired in series. Thus the voltage of each battery is added. If wired in parallel, the mah rating is added together which gives much longer run times, but the voltage isn't doubled . Thus, the 2 2S lipo batteries are 7.4v ea x 2 in series = 14.8v to the ESC / motor. In parallel, the two batteries would still only provide 7.4v to the ESC / motor. You would have to buy a 4S single battery to achieve the required 14.8v. And, from what I can tell, the boats are set up for the 2 battery configuration, so installation of a single battery would be problematic. Also, if you were to wire two 4S batteries in parallel, the weight difference would be huge, although it apparently might run "forever". Then there is the cost of 4S vs. 2S. I have seen alot of commentary on the Gen Ace Lipo batteries (http://www.hobbypartz.com/gens.html) as being very reasonable and preforming quite well. I probably will go with the 2 - 2S and 2-3S batteries to start with, and try out the variations as I go. I understand that it is very important to make sure the C rating and the mah rating on all the batteries is the same.

Let's keep in touch as we travel this new phase of our RC experience together.

EdW.

[EdW.]

Sounds like you're set up to charge ahead (pun intended) with new batteries. I have a single charger that I have been using for the lipo batteries for my aircraft. Up to 6S balancing charger. Don't forget the importance of balancing you lipos!!! If the set up you have doesn't include a balancing function, one can be added to any setup.

[Tom899]

Sounds like you're set up to charge ahead (pun intended) with new batteries. I have a single charger that I have been using for the lipo batteries for my aircraft. Up to 6S balancing charger. Don't forget the importance of balancing you lipos!!! If the set up you have doesn't include a balancing function, one can be added to any setup.
Yes, the FMA PowerLab 6 definitely has balancing and safe parallel charging for multiple packs. I plan on using balancing all of the time, I'll be in no hurry to get my batteries charged.

[96motorhead]

Does anyone have a picture of their blackjack 29 with 4s batteries in parallel? After measuring my hull I can't see the batteries fitting.

[Yckmbfha]

I know this is a bit old but I can put up pictures with two 4s 5000mah in parallel

[96motorhead]

I know this is a bit old but I can put up pictures with two 4s 5000mah in parallelI would be interested in seeing them.

[Yckmbfha]

Here you go.
I made up a small parrallel loom so original wiring stayed the same.
Only other thing I did was trimmed the square corners off of the two upright pieces of ply either side of the motor to make room to slide the batteries in.105102105101105100

[bigern]

Here you go.
I made up a small parrallel loom so original wiring stayed the same.
Only other thing I did was trimmed the square corners off of the two upright pieces of ply either side of the motor to make room to slide the batteries in.105102105101105100
Do you run those batteries that far foward??