Rigging a 42" vintage hydro

[CTdave203]

Hey guys.
I recently bought this 42" vintage hydro which originally was a gas boat. I am going to set it up with electric but am having difficulty coming up with the right motor/kv combo & would really appreciate your thoughts & suggestions
I'm thinking of going with a Leopard 4092 but I don't know much about the "kv" and what the "5D, 4D, 2Y, 3.5D, 3D and 2.5D mean (see options from Leopard below). I believe a Seaking 180 amp esc would do the trick.
Am I thinking about this the wrong way? I don't know if this set up is going to get this boat going really fast or if it will just be a fast cruiser. I don't want to set it all up & go 30mph & then want to change everything out. What do you think speeds will be with a 4092/1480kv? Thoughts?
Leopard choices:

We offer this in 6 versions.
1050 Kv/rpm per volt 5D
1300 Kv/rpm per volt 4D
1390 Kv/rpm per volt 2Y
1480 Kv/rpm per volt 3.5D
1730 Kv/rpm per volt 3D
2080 Kv/rpm per volt 2.5D

winds/rpm: 930Kv 3y Anodized Red (5)
1050Kv 5D Anodized Red (1)
1300Kv 4D Anodized Red (11)
1390Kv 2Y Anodized Red (7)
1480Kv 3.5D Anodized Red (13)
1730Kv 3D Anodized Red (9)
2080Kv 2.5D Anodized Red (13

[tlandauer]

While i am not experienced enough to give you the best possible combination, here are some of the things to consider:
Forget about the winds for a moment, the "Y"s and the "D"s.
This being a gas hull, I take it that it is not light, the size of the motor may not be big enough---here is where I don't want to pretend to be an expert. I would look for something like this to start with:
http://www.offshoreelectrics.com/pro...p-4070&cat=181.
There are other choices, depending on your budget. The Neu motors are top notch and a 1527 or 1530 would also be good picks. I will, however leave this for other experienced people to point you at the right direction.
Depending on the room you have, I would run 6s2p at least. That is two 6 cell lipo connected in parallel. Motor kv around 1500 as a rough guideline.
Forget the 2080kv motor because you will blow something if you run 6s ( 6cell), and if you run 4s, you won't like the speed.
I will get an ESC that is rated at least with a rating of 220A if not more. Remember allowing head room for margin is always a good idea.
Now, to answer the winds, it is a term to describe how the stator is wound (configured). The "Y" wind needs a higher timing---typically around 15* vs. the "D" winds which is set at 0-4 degrees. This has to do with how the stator is energized and for you it only means to program the ESC's timing according to the motor of your choice. Note that some people believe the "Y" should also be set at a lower setting---opinion varies and one thing is sure, "D" winds are set low.
The number before the letter is another way to see the spec of the motor: the lower the number the higher the kv . It also means for a given voltage, the lower number ( higher kv) motor will have a higher amp draw.
The term kv means how many revolutions per volt. For instance, a 2000kv motor running on 4s = 2000(rpm) X 14.8v= 29600 RPM.

[runzwithsizorz]

My thoughts? That hull is basically only good for one thing, -- wide sweeping ovals on fairly smooth waters. The hull is already heavy, and to outfit her it's gonna add another 7 pounds or more.
Unlike that Genesis, which is much lighter, and can get up on plane fairly easy, making it a good match for the Leo 4092, this tank with all it's surface area will need a large amount of *sustained* torque
to pull her out. AND once up on plane, best not ease up on the throttle too much,(and you will), and let her settle back in, for you'll have to ask your motor for another "burst".
I would give serious consideration to a much larger motor, (3500watts+) on 8S. Looks like you have a nice Ct. winter project.
BTW, welcome to the forums! THE expertz will be along shortly.

[dasboata]

That is a old Nitro boat , maybe Dumas or Octura something Fly ??. anyway it is a out dated hull and probably not worth the effort and $$ but that is your choice

[runzwithsizorz]

That is a old Nitro boat , maybe Dumas something Fly ??. anyway it is a out dated hull and probably not worth the effort and $$ but that is your choice

Hey Now! This is OSE, and I've seen a lighted 6 foot Santa cruise a pond. So if someone wants to sail a bathtub, I'm gettin in line for that show.

[SJFE]

I have seen an aquacraft tug fitted with a brushless setup... Not to mention my high speed recovery boat disaster LOL. The hulls neat man.. Go for it!

[CTdave203]

tlandauer, thanks for your time & the education! I'm going to re read your reply a few dozen times & It'll register lol! Thx!

runzwithsizorz Yep, a long cold winter project for sure. You & tlandauer obviously know your stuff. hopefully I can bounce some thoughts off you from time to time.

Dasbota, your definitely right but hey, I'm a glutton for punishment! All it takes is $$$ & anything can be done.

[CTdave203]

tlandauer, thanks for your time & the education! I'm going to re read your reply a few dozen times & It'll register lol! Thx!

runzwithsizorz Yep, a long cold winter project for sure. You & tlandauer obviously know your stuff. hopefully I can bounce some thoughts off you from time to time.

Dasbota, your definitely right but hey, I'm a glutton for punishment! All it takes is $$$ & anything can be done.

Ok, this one gets side lined for a month or two. Onto the P/T boat project! So, engine set ups for this 36" balsa kit? I was going to make this the recovery boat but I just got a cool 30" tug up & running. I bought a bucket of bolts, half finished project & got it going. Ill post a pic later. The p/t I believe should be a 25-30 mph boat. What will get it there? a smaller 40mm motor around 1200 kv running 2s or 4s?
Duh, I really feel dumb here lol. Good thing my 9 and 12 year old kids still think I'm a genius!

[CTdave203]

the p/t project

[olwarbirds]

I have a similiar hull, as stated the Leo motor you selected is a bit small for this hull due to its design and weight. A Neu 1527 or a TP http://www.offshoreelectrics.com/pro...p-4070&cat=181 ... KV choice is going to depend on what voltage you are planning on using...Prop choice is going to be again somewhat dependant on voltage..the T180 esc's are a great product, but I dont think its a good choice for this hull. I really do think considering hull design and weight you should be considering doing a 8S setup to get the torque and some decent speeds.... have fun and welcome to OSE... DJ

[tlandauer]

Keep us posted!

[785boats]

I have a similiar hull, as stated the Leo motor you selected is a bit small for this hull due to its design and weight. A Neu 1527 or a TP http://www.offshoreelectrics.com/pro...p-4070&cat=181 ... KV choice is going to depend on what voltage you are planning on using...Prop choice is going to be again somewhat dependant on voltage..the T180 esc's are a great product, but I dont think its a good choice for this hull. I really do think considering hull design and weight you should be considering doing a 8S setup to get the torque and some decent speeds.... have fun and welcome to OSE... DJ

Agreed.
The 4070 1050kv motor on 8s with a Swordfish 240 will drive that hydro nicely.
Start with an M447 & you'll probably end up on an M450 prop. A prather s235 would be a good prop too. It looks like the hull will have plenty of lift, but as runzwithscizorz stated, it will need the torque to get up.

[runzwithsizorz]

In regard to your P/T project; that hull/keel is not very stable. It will list from side to side wildly just sitting idle with small pond ripples. A sharp turn and you will submerge part of the deck. Speed is out of the question, and frankly, she just would not look good at over 20mph. She is what she is. Keeping water out of this hull is near impossible. At the low speeds, water circulation is a concern. I would go with a brushed motor system on this build. The Traxxas fan cooled Titan 550 with the small prop should be sufficient. Should you add weight, and want more head room the 775 should fill the bill. http://www.funrcboats.com/ProductInf...ductid=TRA5675