Question regarding size of batteries and prop

[barryaclarke]

I am building a 30” Apparition using a Leopard 4072 1600kv and a Seaking 180 ESC. I’m really new, so this maybe a funny question, but I was thinking of using either 3S or a 4S when a question came to mind. If at first I were to use a pair of 3S batteries and decided later to hook them up in series doubling the voltage, is the only thing I need to worry about is prop size since the Leopard and Seaking can run on both 3S and 6S? Next, what are good starting points for prop sizes for the three voltages or should I just stick with a 3S or 4S and not worry about 6S?

[fweasel]

A 1600kV motor is really setup for 6S voltage in terms of RPM. There's nothing preventing you from running your setup on 3S or 4S with two packs wired in parallel. You'll get a ton of run time, but the speeds will be pretty pedestrian at 1600kV. The TFL Apparition is the same/similar hull as the Fightercat Rivercat, which will give you more results searching both here and youtube for setups and builds. If you want to run 4S, look for a new motor closer to 2000-2200kV for a sport setup. You could go as high as 3000kV if you wanted a SAW boat that would only make a handfull of straight line passes on a set of batteries. If you stick with the 4072, the boat will certainly be a rocket, but the hull is narrow and doesn't turn as well as some wider cats do, so keep that in mind for what you want performance wise. As far as props, you could start in the 42-45mm range and work you way up in pitch as you tune the setup.

Where in IL are you located?

[barryaclarke]

A 1600kV motor is really setup for 6S voltage in terms of RPM. There's nothing preventing you from running your setup on 3S or 4S with two packs wired in parallel. You'll get a ton of run time, but the speeds will be pretty pedestrian at 1600kV. The TFL Apparition is the same/similar hull as the Fightercat Rivercat, which will give you more results searching both here and youtube for setups and builds. If you want to run 4S, look for a new motor closer to 2000-2200kV for a sport setup. You could go as high as 3000kV if you wanted a SAW boat that would only make a handfull of straight line passes on a set of batteries. If you stick with the 4072, the boat will certainly be a rocket, but the hull is narrow and doesn't turn as well as some wider cats do, so keep that in mind for what you want performance wise. As far as props, you could start in the 42-45mm range and work you way up in pitch as you tune the setup.

Where in IL are you located?

Thank you for the reply. Looks like I'm going to be using 6S but was hoping I could use a lower voltage. I'm located in Bourbonnais, IL that's about 50 miles SSW of Chicago.

[Vin-m]

I do twin setups in that hull w good success but kfxguy here on this site builds the best single motor set ups for that hull. Hit him up and I'm sure he will help you out.

[barryaclarke]

Being new to the site, how do I contact "kfxguy?" Your boat is interesting. About seven years ago I was waiting for a carbon Fighter Cat that I had on order and was going to run twins. During that time, I was collecting what I thought I would use to build it and was the reason why I ended up with the two Leopard 1600KV's. After about a year, the guy went out of business and I never got my cat. It was just recently I got interested again and decided to get back into RC boating. Now that I'm a little smarter, I will now buy the hull first and then the parts. Are you located in Illinois too? Thanks for your help....Barry

[Vin-m]

I'm in Florida. To find him just use the search tab in the upper right corner and type his name in. That should bring his profile up. Then just send him a message.

[barryaclarke]

Thanks again...Barry

[fweasel]

Barry, I'm in IL, in Chicago to be exact. We usually run in Schaumburg during the summer.

[barryaclarke]

Hi,
You caught my interest with twin builds and the pic of a fighter cat. I have one on order and have a few questions. I have two SeaKing HV V3 130A ESC and also two Leopard 4074 15k motors. I was thinking of going with the 4082's but wonder if I would be pushing the ESC's to much with either motor and maybe going with the 3074's. I'm racing and just want to go out and have some fun with this hull on 6S....Barry

[Vin-m]

It just depends on what you are going for and what you want out of the boat. I do seaking 120s and leopard 2860s around 2800kv and run them on 4 cells. It's a very dependable set up w long run times and you'll be going about 65 mph. Had mine for 6 years not one problem

[barryaclarke]

Since I already have the SeaKing 130's and the Leopard's 4074 1500kv, that they will be OK or do you think maybe I could bump up to the next larger motor or just run with what I have?....Barry

[Vin-m]

4074 1500kv. Would work for a single drive. They will not fit for a twin. And 6 cell batteries will not fit. The hull is only 32". Get a Zonda hull if you want to run that set up as a twin it'll fit perfectly. Zonda is the same hull as a rivercat just 41".