Okay - thanks! That makes a lot of sense. I'm really excited, cannot wait to see some solid rooster tails again.

Originally Posted by Shawnner

I like that thinking. I can run lipo without all the cut off settings set up by the new esc systems? Sorry for such noob questions.- I've read all the "read this first" type posts on lipo and still feel overwhelmed.

I would NEVER run a LiPo in a boat without the cutoff set. The reality is that very bad things happen when you get these packs below 3v per cell.

^^ Cutoffs are only good if you're pushing packs hard... I can FULLY empty the pack in my stadium truck (5400mah back into a 5000mah pack) before it hits the LVC (which is set to 3.7v/cell on my ESC). Even the LVC in my Motley Crew doesn`t come in early enough to not over discharge the packs (I consider taking more than 80% out of them over discharging).

I much prefer to time my runs and go by feel than to rely on the LVC.

Since my boat is already set up for older 540 sized motors, like my Astroflight 05 cobalt it seems I'll need to stick with that 3650 or similar leopard motor.

The specs on the old Astroflight box state 400 Watts @ 24,000 rpm for the power and up to 8 cells (NiMh). We ran 8 cells back in the day but also had a few 9 cell packs. It measures 60mm x about 35mm (plus those exterior magnets) so I have plenty of clearance for the 3650.


That SeaKing 180 does look rather large and I think the water cooling routing is what will mess me up the most. My old Tekin marine ESC measures 85mm long x 30mm wide x 20 mm high. I also never ran the water cooling since it never really heated up that much and also nestles into the back of my hull with the radio, each in a single balloon. Man, water cooling this boat is admittedly gonna be a difficult task. But it looks like I will need a SeaKing or Turnigy 120 - they look to be the exact same unit with different labels - an assumption on my part and probably wrong.

I'd be surprised to see those motors make 400 watts on nimh packs, but they're definitely stronger than most car/truck motors.

400 watts on 8 cells would be about 45a constant, which is a lot of current for nimh packs to deliver.

A seaking/turnigy 120 (they are the same minus the sticker) will be the easiest bet for water cooling since the lines run front to back along the ESC.

Ok cool. I agree on the Turnigy, it looks like the right answer in terms of dimensions and specs along with a great price. Appreciate the help, big time!

You can either move the boat with voltage (4s) or with amps (2s) I'm going with 3s in mine. Shawn, you have a PM on OSE!

Hydrofoils Inc. 60G Test, February 2013 (1 min 4 sec)

Hydrofoil - Hydrofoils Inc. RC Hydrofoil Promo (3 min 34 sec)

Couple YouTube clips you may like.

Here ya go. I had a subscription to boat n ship and still have this mag due to the hydrofoil, great inspiration.

Oh yeah, thanks for that! That boat was a beast, of couse that pic is just a photoshop. But you can see it running in the beginning of the 2nd YouTube - the older movie. He still has it but does not run it. It's truly nice to hear the hydrofoils inspired folks back then and you are still interested today!

I used to own one of these and sold it quite some time ago. I only ran it on 6-7 cells and a Graupner 500 motor.

If you have any questions regarding foil sharpening shape maybe I can help.

Yes, the 500 motor fits in there but a T180 esc will not and is far too heavy for this sized boat... Well at least to achieve the correct balance for it to ride properly.

From memory the gent from Hydrofoils Inc in FL told me that the boat should ride tail high with the nose slightly downward.

The foils need to be razor sharp. The horizontal foils need to create lift and the rudders vertical portion should be sharpened on both sides again razor sharp.

For some reason I had a hard time mounting the rudder as per instructions and phone calls.

I settled on adding a hardwood block to extend the rudder out so as to avoid contact with the Propeller.

I only ran it twice and got frustrated with it. Kinda wish I kept it but, got a few decent bucks for it anyway.

Since you have the 3650 size motor give it a whirl. If I had it still I'd gut it and put a 2860-5050kv Tacon in it and a T120, maybe just a T90 because it's lighter. A nice detongued x432 and it would ride on the prop and blade tips. Batteries I would use 2S Nano or Dinogy 3400Mah -4000mah max. This gives you flexibility to move components around for proper ride attitude.

Some days I can't remember what I had for lunch but, these things are still fresh.... crazy.

As for exact CG, I can't say but, tail up, nose down he said.

"tail up, nose down"

So many things work out well that way, you’d think they’d simply teach it in school.

FYI...Shawner is the son of the fella that made these hydros . So he has intimate knowledge of these 'foils.

Originally Posted by BACKEMFNRG

I used to own one of these and sold it quite some time ago. I only ran it on 6-7 cells and a Graupner 500 motor.

If you have any questions regarding foil sharpening shape maybe I can help.

Yes, the 500 motor fits in there but a T180 esc will not and is far too heavy for this sized boat... Well at least to achieve the correct balance for it to ride properly.

From memory the gent from Hydrofoils Inc in FL told me that the boat should ride tail high with the nose slightly downward.

The foils need to be razor sharp. The horizontal foils need to create lift and the rudders vertical portion should be sharpened on both sides again razor sharp.

For some reason I had a hard time mounting the rudder as per instructions and phone calls.

I settled on adding a hardwood block to extend the rudder out so as to avoid contact with the Propeller.

I only ran it twice and got frustrated with it. Kinda wish I kept it but, got a few decent bucks for it anyway.

Since you have the 3650 size motor give it a whirl. If I had it still I'd gut it and put a 2860-5050kv Tacon in it and a T120, maybe just a T90 because it's lighter. A nice detongued x432 and it would ride on the prop and blade tips. Batteries I would use 2S Nano or Dinogy 3400Mah -4000mah max. This gives you flexibility to move components around for proper ride attitude.

Some days I can't remember what I had for lunch but, these things are still fresh.... crazy.

As for exact CG, I can't say but, tail up, nose down he said.

Originally Posted by Th3UmBrA

FYI...Shawner is the son of the fella that made these hydros . So he has intimate knowledge of these 'foils.

Thanks man! Yeah Th3UmBrA is correct but I do appreciate any input. I'm especially interested in hearing about our old hydrofoils and completely new to brushless.

We made so many of those boats I remember that wooden block well. I had a piece of bent aluminum dowel that I used. The trick was to slide that block down on its back, glue side up, and flip it up at the last moment.

Well it's been nearly a year since I officially started my rebuild and I've made a lot of progress. Figure it's time I shared the latest video for my "one year anniversary". This was taken in April, I'd strapped an iPhone to my radio. Hope you don't mind the shakiness.

The biggest challenge has been fitting everything into the small hull, especially introducing water cooling but I've managed to make it work. Next on my list are a stronger collet/coupler and a faster/stronger servo. Both are suffering a bit from the nearly double power. This run is primarily half throttle throughout. When I finally start to get on it at the end the flex cable spins right out of the current collet. Hope you all get a kick out of seeing a unique brushless FE Hydrofoil boat run even for just a few minutes!!

Hydrofoil - RC Hydrofoil - Remote Control Hydrofoil - Hydrofoils Inc. Zytiron (3 min 15 sec)