Scratch built ribs and outboards

The blue rib proved to be too heavy, though I did get some exciting footage. So I will try the boat in the photo, its lighter. I've added a curved screen to the go pro to stop drops of water sitting on the lens. I printed the mount and slid in some clear plastic.

 

It didn't work, boat weaved about, guess the hull is wrong shape. So back to a rib, but this time under its own power, just enough so it can be towed. The exciting prospect is it might be able to pull out to one side then the other just like real water skiing.
We now have two kneeboarders to put on a show at the next open day in August.
I bought a hull to do another Neptune rib, then found a new supplier for the waterproof canvas covering, he does a blue one called Teal which I think I might go with.

 

We opted it before with the monoski: would be great to have some control over the one behind the boat. I guess you need two people for that. Would add to the already great realism!

I have a wakeboard here, and did some waterskiing in the past. The way the wakeboarder is pulling on the stern is like the real deal! You can see in your video it influences cornering!

An old friend of mine weighting over 100kg could "steer" the boat even with a 50HP outboard while monoskiing.

 

New Suzuki outboard........so with the rain upon us I got on the lathe to make the shafts for the gearbox. Then I made the cone drive to fit the prop, quite a tricky thing to make but luck was on my side, so nice snug fit.
I cut the 5mm thread with a die , holding the shaft in the lathe, lathe turned off , I stuck the chuck key in and rocked the die holder and chuck back and forth till I had a thread.
The props come with a 4.76 hole, who thought that one up, so being 3 bladed it fits in the chuck and I drill it out to 5.2mm. 5.2 is just right for me to have a 5mm thread and 5mm nyloc nut to hold the prop on. The gears are from the jet fox gearbox, no wear on them, so put to good use.
The spacer is there in case I want to fit a larger diameter prop which would also be longer in length, but unlikely as I seem happy with these 46mm diameter TFL 3 blades.
Still raining, time to watch some tennis, semi final, Wimbledon. Alcaraz won in 3 sets all 6 to 3 games, should be a good final on Sunday.

 

The 2 part end cone works well, even though it doubles the printing time.

 

The gearbox is all assembled and filled with oil. The sealant i used is a bit messy but so long as it does its job.

 

We have had endless rain this month so plenty of time to work on the new Suzuki outboard.

 

This film was meant to have some boat to boat shots, but when we came to film th camera boat wouldn't work. When I got home I found the motor wires all 3 disconnected under the deck, yet I felt sure I had tested it, loosing the plot as we say.
Ready for the final assembly of the new Suzuki outboard, can't wait to get it on the Neptune rib and try it

 

Suzuki outboard black
So to be ready for tomorrow's meeting I put some hours in today. I had to make my own adapters for the motor wires to plug into, because the engine I took off was 5.5mm plugs , the new motor 6mm, see photo. The paint I bought was rubbish, serves me right trying to save a few pounds, now I am going to have to redo the cowl if not the whole engine
Now the blue Yamaha is freed up I can service it, and it needs it too, last done 10 months ago, Oct 2022. It needs a new vertical bearing support tube, the one in now was loose, so it will have been spinning round. It will be interesting to see how the gears have faired.
Once serviced it's going on the speed boat, which to now has only been run with my jet outboard, I've entered it in the fast electric section of our next open day.

 

Amazed, the gears are still like new, so I made a great choice in using them. Look at the photo to see cracks inside the gearbox, so I am printing new gearbox halves and I will paint them inside this time for more protection from the oil.
New Suzuki outboard....very pleased how it performed today, it got noticeably quieter as it got run in only took a few runs. Going as fast as the hull allows she was hitting 86 amps, so that's OK. Pulling the wake boarder at a steady pace gave 26 amps.



Today..boat to boat filming

 

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I have added a 50mm extension to the hull to cut down on splashing from water hitting the outboard. Still to be tested, but hopefully it will cut down on water getting into the boat.

 

Be aware that you basically lengthen your hull this way when the hull glides over the water (not displacing). This could influence the location of your CoG a bit.

 

F1h2o
Funny how the back end stopped printing with 10mm to go, and by making 2 slots in the hull it now slides perfectly down in front of the transom . 2 bolts through the transom will secure it so access to the steering servo can be had. I can draw a bracket for the servo with a tray above to hold the esc. I held my outboard to it, perfect fit top of cowl lines up with top of back end, lucky again. So where do I line the prop up so it stays underwater at speed, never had twin hull boat before?

Update..the speed boat didn't like the prop outboard too much torque roll, so it's now back to a jet outboard.

 

Update on splash guard....boat completely dry inside, but now I get ventilation on the prop, so I have to cut away some of the guard, see if I can get the best of all worlds.

 

My F1 project is taking shape, although it's a big model it's still tight in the fuselage, so I've printed a tower so everything fits in the rear end.

 

That prop is sticking under water ?
I doubt that wil work on a tunnel.
You need to lift the motor,all the way up that only the axle is touching the water.
And the prop becomes a hydro prop.

 

Prop way up ,center of the shaft touching the water.
That's a good starting point.

 

I do have ways of raising the engine, but so far I've found my props suck air in and loose traction if too near the surface. Which is why I added the hydrofoil cum anti ventilation plate. However I could produce a special short shaft version of my outboard just for this model, the mid section being 20 to 25mm shorter. Instead of filling with oil I would pack it with high quality grease, sealed for life, this would help me make it shorter. I think testing on the water will show which is the best way. I might make a battery bay cover just for testing with a gps window and a watt meter.