Looking for information.

[1coopgt]

I'm planning on getting a 1/8 scale Hydro from RC Boat Company around February hopefully. So I've been doing research on needed parts and where to get them. I'm at the point where I need to start asking questions.

1. I know it's dependent on motor and battery size but how fast can I expect the hydro to go?

2. I'd like to run 8 to 10s ( pair of 4s or 5s batteries) What size motor should I be running ?

3. What works better with the 1/8 scale Hydro's a 2 blade prop or 3 blade.

I don't have any sanctioning bodies in my area so I'll just be running on local ponds and small lakes. I'd like to be able to get the boat into the low 80's if possible.

I know nub questions but I have to start somewhere . Thanks for any responses.

[klloyd67]

I'm planning on getting a 1/8 scale Hydro from RC Boat Company around February hopefully. So I've been doing research on needed parts and where to get them. I'm at the point where I need to start asking questions.

1. I know it's dependent on motor and battery size but how fast can I expect the hydro to go?

2. I'd like to run 8 to 10s ( pair of 4s or 5s batteries) What size motor should I be running ?

3. What works better with the 1/8 scale Hydro's a 2 blade prop or 3 blade.

I don't have any sanctioning bodies in my area so I'll just be running on local ponds and small lakes. I'd like to be able to get the boat into the low 80's if possible.

I know nub questions but I have to start somewhere . Thanks for any responses.

Accu-Tech Hardware or here on OSE is great place for parts. 80's would require 10S, a very light hull and would probably struggle to stay on the water. Low 60's and stable is very achievable, 80's not impossible. Likely you would run a 800-900kv motor that can spin a larger prop. Whether 2 or 3 blade depends on the hull, trim and weight, the largest 2 blade you could run would probably give you best top-end. There are plenty of guys on here with way better knowledge of this than me, I'm an ex-nitro guy.

[meangenesracing]

I'm planning on getting a 1/8 scale Hydro from RC Boat Company around February hopefully. So I've been doing research on needed parts and where to get them. I'm at the point where I need to start asking questions.

1. I know it's dependent on motor and battery size but how fast can I expect the hydro to go?

2. I'd like to run 8 to 10s ( pair of 4s or 5s batteries) What size motor should I be running ?

3. What works better with the 1/8 scale Hydro's a 2 blade prop or 3 blade.

I don't have any sanctioning bodies in my area so I'll just be running on local ponds and small lakes. I'd like to be able to get the boat into the low 80's if possible.

I know nub questions but I have to start somewhere . Thanks for any responses.

Where in NY are you located? I have a 1/8 scale ML boatworks with a neu 1527 on 10s runs 63. Mph with a x447/3 prop

[1coopgt]

I'm in Rochester.

Sounds like I need to reset my goal a little bit for the speed . Thanks Klloyd67. So For an 1/8 Hydro how do you determine the motor you run in the boat?

[785boats]

R/C Boat company for cowlings & wing kits etc.
http://www.rcboatcompany.com/Cowlings.html

Having built & raced a few 1/8 scale hydros in my time, I would say that 80mph would not only be very difficult to keep on the water but would also look totally wrong. Too fast for scale.
Best to get an ML Boatworks sports hydro kit for that sort of speed.
One of mine runs a 1527/1y on 8s with a Prather s235 prop & 240A ESC. It can run in the low 70's. It needs a fair bit of weight added in the nose to keep it on the water.

A lower kv motor, as suggested above by klloyd67, & a larger prop would be more efficient though.

[meangenesracing]

R/C Boat company for cowlings & wing kits etc.
http://www.rcboatcompany.com/Cowlings.html

Having built & raced a few 1/8 scale hydros in my time, I would say that 80mph would not only be very difficult to keep on the water but would also look totally wrong. Too fast for scale.
Best to get an ML Boatworks sports hydro kit for that sort of speed.
One of mine runs a 1527/1y on 8s with a Prather s235 prop & 240A ESC. It can run in the low 70's It needs a fair bit of weight added in the nose to keep it on the water.

Not 70 mph. Correct?

[1coopgt]

R/C Boat company for cowlings & wing kits etc.
http://www.rcboatcompany.com/Cowlings.html

Having built & raced a few 1/8 scale hydros in my time, I would say that 80mph would not only be very difficult to keep on the water but would also look totally wrong. Too fast for scale.
Best to get an ML Boatworks sports hydro kit for that sort of speed.
One of mine runs a 1527/1y on 8s with a Prather s235 prop & 240A ESC. It can run in the low 70's. It needs a fair bit of weight added in the nose to keep it on the water.

A lower kv motor, as suggested above by klloyd67, & a larger prop would be more efficient though.

Beautiful boat you got there. When I mentioned 80 mph it was/is because I don't know anything yet. I can tell I've got a lot to learn and once I get started on the build it's going to take a while to complete just due to cost of some parts. Budgets suck but I'll need to stay with in it.

Is there any good material I can read about the motors and sizing . So that I can understand things better? Also figuring out how to pick out the right ESC and Bec if needed.

I looked In the OSE store and found the NUE 1527 ,there were close to 10 choices that this motor can be configured to. Then looking at ESC's I found the Swordfish X+ 150A ESC I'm thinking will work with the 1527. But I'll be honest I have no idea. LOL This is a big learning curve .

[Mike W]

The ZTW200 has been working well for a few 1:8 scales at our club, and a larger 40mm at around 850KV is quite standard for 8S in 1:8 scale. Gonna be building one myself this winter.

[785boats]

Meangenesracing.

Not 70 mph. Correct?

No, probably not. That was one of the early test runs.
But a later run was clocked at 117kph (72mph).
Here it is but from the side view. The first video, in my previous post, was filmed from the launching dock.
https://www.youtube.com/watch?time_c...&v=1JtH-omu4PY

1coopgt.
The 150A ESC might be a bit small. The 200A or 240A would be a better choice in my opinion, with a 12s voltage rating.
The 1527 1.5y 850kv seems to be the favorite for an 8s set up.
A cheaper option would be the TP Power 4070 10D 830kv. I run a lot of TP motors in my boats. They work well.

I don't think I've seen a list of power setups for different boat types & sizes. Someone may know of one. There are so many variables.

[meangenesracing]

Meangenesracing.

No, probably not. That was one of the early test runs.
But a later run was clocked at 117kph (72mph).
Here it is but from the side view. The first video, in my previous post, was filmed from the launching dock.
https://www.youtube.com/watch?time_c...&v=1JtH-omu4PY

1coopgt.
The 150A ESC might be a bit small. The 200A or 240A would be a better choice in my opinion, with a 12s voltage rating.
The 1527 1.5y 850kv seems to be the favorite for an 8s set up.
A cheaper option would be the TP Power 4070 10D 830kv. I run a lot of TP motors in my boats. They work well.

I don't think I've seen a list of power setups for different boat types & sizes. Someone may know of one. There are so many variables.

73 mph that's fast mine on 10s only does 63 mph and I thought that was fast. I didn't think 8th scales could go that fast. Is that boat one of Mike's kits or a fiberglass RC Boat company? Mines the Squire shop one of Mike's kit

[1coopgt]

Meangenesracing.

No, probably not. That was one of the early test runs.
But a later run was clocked at 117kph (72mph).
Here it is but from the side view. The first video, in my previous post, was filmed from the launching dock.
https://www.youtube.com/watch?time_c...&v=1JtH-omu4PY

1coopgt.
The 150A ESC might be a bit small. The 200A or 240A would be a better choice in my opinion, with a 12s voltage rating.
The 1527 1.5y 850kv seems to be the favorite for an 8s set up.
A cheaper option would be the TP Power 4070 10D 830kv. I run a lot of TP motors in my boats. They work well.

I don't think I've seen a list of power setups for different boat types & sizes. Someone may know of one. There are so many variables.

Thanks for the info about the ESC.

Guys I really appreciate the info and help !

[785boats]

1coopgt.
That's what these forums are all about mate.
Here's another tip. The ML Boatworks kits are a framing kit only. Mike offers a combo package for the kits, with all the basswood sticks & 1/16" ply sheets needed to finish the hull. Unless you can buy those items cheaply somewhere else, I suggest you get the combo bundle. Even with the exchange rate & postage, it is cheaper for me to buy it with the kit than buying it here in Australia.

Did you have a particular boat in mind? There might be a build thread on whichever one you have chosen.

Meangenesracing.

Yes it is one of Mikes kits. This one.
https://mlboatworksrc.com/shop?olsPa...701-kit&page=5

As you can see, like a lot of his kits, it will make a number of other famous boats too.
The cowlings are from 'The R/C Boat Company' though.

That sort of speed is fine for demonstration laps But as you could see, it was dancing on the edge.
For racing I had to tie it down a bit, so it's probably only doing mid 60's. Race water gets pretty choppy as you know.

[1coopgt]

I'm planing on building the 2008 U-1 Ellstrom E-Lam Plus using the RC Boat Company SG121H Fiberglass Hull kit. From watching videos of a guy building wood hull Hydros I don't have the room or the proper tools to do a proper wood hull justice. I haven't build a wood hull boat since I was 15. I'm 58 now. LOL

I've been digging in a lot in the scale Hydro section looking for Fiberglass hull 1/8 scales. A lot show the builds but the ones I've found they didn't say what motors or esc's were being used. I did find one that said what motor he was using . I made sure to subscribe to the theads that I've found so I can go back to them for reference .

The other thing I've been looking into is where to put the batteries. Couple I've seen the guys put them in the nose and another I found the person put one battery on each side of the motor perpendicular to the centerline of the boat. Where the fuel cells go for a nitro boat I'm assuming. Not sure what would be better. In the nose (cockpit area) would help to keep the front of the boat more planted I assume.

Yeah your second video you could tell she was dancing on the edge. Very cool.

[785boats]

Sorry man. Missed your last post until now.
The CoG needs to be around 1-1/2" - 2" from the heels of the sponsons.
So the best thing to do is place all the gear in the hull like motor, ESC, stuffing tube shaft etc, with the strut & rudder bolted on, & cowling in place etc.
Then place the batteries where you can, & move the motor & ESC & batteries around to achieve that CoG, with space to move the packs fore & aft a bit for fine tuning.
At least, that's what I do.
If you can't get the batteries far enough forward then you will need to add some weight.

[1coopgt]

Sorry man. Missed your last post until now.
The CoG needs to be around 1-1/2" - 2" from the heels of the sponsons.
So the best thing to do is place all the gear in the hull like motor, ESC, stuffing tube shaft etc, with the strut & rudder bolted on, & cowling in place etc.
Then place the batteries where you can, & move the motor & ESC & batteries around to achieve that CoG, with space to move the packs fore & aft a bit for fine tuning.
At least, that's what I do.
If you can't get the batteries far enough forward then you will need to add some weight.

Thank you !!!