Not So Boldly Going Where Others Have Gone Before. RC Nano-Hydro

[NativePaul]

Yeah the cowl is pretty ugly, I did some more sanding to the canopy and it is not quite as bad now, but it will never be pretty. The glue was so slow I used a single cone rather than the sleeker lobsterback I was planing but would have added an extra day to the build.

It won't be a be an atlas, I know they are popular, but it is one of my least liked unlimiteds. If it is lucky it will get some sort of sharpie art.

The Plans are in the first post, I just stretched the afterplane by half an inch, added 10 mm to the tunnel width, and 2.5mm to the sponson length, so blowing up the plan shown by 8% would near as damn it give you what I built.

The longer the afterplane the better it will ride, it is so light the CoG is not an issue, as it stands the battery weighs more than the hull and can be fitted forward of the sponson heels, I can get the CoG in front of the sponson heels without having to put anything in the sponsons, adding hardware will move that back a lot, but I cant imagine it being an issue getting the CoG to 20% of the afterplane, which is where I think I want it.

The one thing that worries me is the size of the prop hub (6mm) is the Kyosho hub as big? I really don't want to, but I can foresee having to give it a ski to hide the huge hub hydrodynamically, which would require me to move the CoG backwards after the build, so I may have to make the battery removable.

[Dr. Jet]

The Kyosho prop hub is 4mm.

[kfxguy]

Awesome project! Good job!

[NativePaul]

A 4mm hub would be sweet only, a touch bigger than the strut. you said in your thread that the Kyosho was about 14mm diameter, is that measured and close to, or a guestimate? I was well off on my guestimate of the Rivos props thinking they looked 20-22mm but were actually only 17.3mm.

Could you take some pics of the Kyosho props so I can see the pitch ramp, if the Kyosho is less progressive it may need less detongueing and have as much finished blade area despite being 3mm smaller.

Do you have a part number and/or a link for the Kyosho props, my google skills are failing me and I cant find them without driveshafts attached.

[Dr. Jet]

I measured it at 14mm. Not a very progressive ramp, not a whole lot of tongue. I think it's pretty much ready to go as-is. The only way I found one was to buy the rudder bracket set. https://www.ebay.com/itm/Kyosho-BM15...19.m1438.l2649

[NativePaul]

Thanks for the link, that is a totally different and much better looking prop than the Kyosho ones I found with the driveshafts attached. While I cant find one closer than Japan either, that part number found a manual and confirmed that the prop only has one part number which is for the whole rudder bracket set, so is not available separate.

Is the bore 2mm? Could I get a pic looking down a blade too please? Sorry for the questions but it will cost over £10 to get one to me as opposed to under £7 for 3 of the Rivos props, so I want to be 100% sure before purchasing as I can't afford to buy a few to work differently.

That prop makes your strut look huge, the Rivos props I got may be better suited to you with their 2x6mm hub, bigger diameter and low initial pitch, it should have more hole shot to maximise your chances of plaining, worth a go if it doesn't work with the Kyosho.

[Dr. Jet]

I don't recall exactly what the bore is. I think it's about 2.2 or 2.3mm. I just turned down a piece of brass until it was a push fit.

I want to start with the smallest prop I can find as I really don't know how the motor will handle the load. It is an inrunner (lower torque than an outrunner) and it has a fairly high Kv for 2S (4500 rpm/V). On my mini hulls (17" or so), I run outrunners between 3000 and 4000 rpm/V on 2S with great performance on props between 26 and 30mm.

Photos to come....

[Dr. Jet]

Here you go....

[NativePaul]

Thanks, looks good, 2mm Bore?

[Dr. Jet]

I think it was 2.2 or 2.3. I never measured it, I just turned down some stock until it fit. I'll measure it now.

[Dr. Jet]

The narrow end of my tapered shaft is 2.04mm. I didn't pull the prop to measure the wide portion of the shaft, but it is probably 2.06~2.07mm; so the bore is most likely 2mm (plus or minus manufacturing tolerances).

[NativePaul]

I made the hardware tonight.


Damn the weight of the stuffing tube.

[Dr. Jet]

Photos?? Photos of the inside; the motor mount and such??

[NativePaul]

I have not opened her up and fitted it all yet, maybe I will get her finished tomorow, here is the hardware though.
nano_7853.jpgnano_7856.jpgnano_7860.jpgnano_7863.jpgnano_7866.jpg

[NativePaul]

All together now, 3.4g for all the hardware, .6g of which is a 20mm stuffing tube.
nano_7869.jpg