Another Hare-Brained Idea

[Dr. Jet]

That would have been the last one I would have guessed, you said you didn't want a rigger as they are too ugly, then you got a Redbird!

I never said 'riggers were ugly; I IMPLIED they weren't as sexy as models that vaguely resemble full-sized boats.

The Redbird isn't as ugly as it is Quirky. A full-sized version could actually exist. Here's one that's similar.

[Dr. Jet]

Plenty of Room

Who says there's no room in the minis? I have room for at least TWO square inches of flotation foam after I install the motor and jacket...

[NativePaul]

I am aware of batboats, H&Ms batboat is a great hull and was dominant in Mono2 in the early 2000s, my biggest boat is an MHZ batboat. The redbird came out when the introduction of the Mini Mono class was rumoured, and I believe it was an attempt at scaling down the features of the batboat, but not a very successful one, they were pretty common on the race scene as one of the first puropse made Mini Monos, but had no advantage over 10 year old Mono 1s from back when they were mini size, and they were completely outclassed by the next generation of Mini Monos when they came out. If you ever want to buy another hull of similar size, please ask me for recommendations.

[Dr. Jet]

.......... and they were completely outclassed by the next generation of Mini Monos when they came out. If you ever want to buy another hull of similar size, please ask me for recommendations.

I think we have different priorities here. I am not the least bit concerned with building a competitive all-out racer for organized competition. I run at a pond where 99% of the people fly float planes. Every now and then, the occasional guy comes out with a ProBoat JetJam or one of those Asian Cabin Cruiser models. I am interested in building something a bit whimsical in appearance that runs good enough and looks bizarre enough to elicit questions and quizzical gazes. This is supposed to be fun, not serious.

Kinda like the old flying days. Some guys flew F5B and F5D. Cool stuff. Wicked fast! I liked to fly scale jets. Cool stuff in a different way; we couldn't race the jets very easily. They would never do well on a pylon course and might get one lap in an F5B round.

If I were building an all-out racer, I'd probably avoid Oliver's hulls all together as they tend to be overly strong (read heavy). I have a Micro Drifter that's been on my shelf for many years as well. Maybe I'll throw a pair of Helicopter motors in that.

[NativePaul]

I know you are not a racer, but racing breeds better boats, and who doesn't want more efficient hulls that can go faster with the same power or get longer runtimes at the same speed, have better handling and cope better in rough water? There are whimsical and bizarre looking race boats, the redbird was one of them, Rasch and Tenshock make a winged mono which I think would still fit your aesthetics, and while they are not the best race boats out there, they are still a huge leap ahead of the Redbird in every aspect.
P1010029.JPG

I race one of Oliver's boats, and yes it is heavy, but you can ask him for a lightweight version at no extra charge (unfortunately I thought all his riggers would come with lightweight layups, as I thought riggers are so ugly nobody would run one if they weren't racing, so I didn't ask him).

I think we are pretty similar characters, I raced cats against riggers for may years before I got fed up with the disadvantage too much and turned to ugly riggers, and when i took a break from boating and went flying I flew many types, but put way more time into making EDFs than any other type of plane.

[Dr. Jet]

During this period when we are all hiding from the dreaded Chinese Coughing Death, I did pull out another languishing, yet nearly completed project from the shelf. One huge advantage of the case transport/storage arrangement is your hulls stay clean and ready to go at a moment's notice. This is a VERY OLD Vortex hull I bought when they first came out. It had a turbine-style hatch that warped into something resembling a potato chip, so I threw that away sometime during the early Obama Administration years. I made a new hatch from a sheet of basswood and one of Randy Naylor's micro hydro hatches. Power is an 1107/2Y NeuMotor on 2S. FE Calc says I can run on of those CNC 3-bladed M832 props and be right in the 35A area. The one and only time I ran it, I used a de-tongued X430 and it was clearly not enough prop.

I have a de-tongued X632 in my inventory and it will get that prop next time out. I just ordered one of those M832/3 props.

[Dr. Jet]

Back to my Hare-brained idea, much to the chagrin of Paul......

The motor finally arrived. There's PLENTY of room in the minis! I had to slide the cooling jacket rather far forward to clear some of the 'glass and carbon at the bottom of this hull (the hull bottom is VERY strong! ). As you can see, I haven't installed the cooling water through-hull outlet. It's going to vent into the flood chamber, just forward of the battery. I have a guitar project that needs some epoxy in the bridge post holes, so I'll do the outlet at the same time I fix the guitar.

The next step will be the bathtub (or in my case, kitchen sink) test. See if this flood chamber thing works....

[Dr. Jet]

Kitchen sink testing complete. The good news? The self-righting feature works! The Bad news? Water is getting past the ball bearings and making its way into the hull.

I might be able to seal the shaft with some small O-rings. I found some 2mm ID x 5mm OD O-rings that might do the trick.

[Dr. Jet]

So I've been thinking how to seal the driveshaft.

The driveshaft itself is a 2mm solid rod. It rides on 2 ball bearings that are 2mm ID x 5mm OD, with the rear bearing being flanged. The stuffing tube is a 6mm OD (5mm ID) brass tube. In the forward part of the stuffing tube is a short length of 5mm OD tube that acts as a stop for the forward ball bearing. A free-floating piece of 3mm OD brass tube rides on the driveshaft to act as a spacer between the ball bearings.

My plan is to install a 5mm OD x 2.5mm ID nylon washer into the stuffing tube, followed by a 5mm OD x 2mm ID Viton O-ring and then another 5mm Nylon washer to create a seal. These washers have a larger ID than the shaft so there will be no contact between the shaft and the washer. Next, the ball bearing and a new 5mm OD spacer tube go into the stuffing tube. I'll duplicate the washer/O-ring/washer assembly at the rear bearing as well. By carefully trimming the spacer tube to the proper length, I'll be able to put a small pre-load on the washers, thereby squeezing the O-rings ever so slightly when the shaft is clamped into the coupler. None of this will be permanently installed in order to make repair and maintenance possible.

The contact surface area where the O-ring rides on the shaft will be really small, so I don't expect much friction with this concept. The shaft will get a thin layer of marine grease where the seals make contact.

I may only need one seal at either one end or the other and this concept will accommodate that by simply using the appropriate length spacer tube.

[Dr. Jet]

Well, after a completely unacceptable delay (that's a story in and of itself) my tiny O-rings have arrived and my Hare-Brained idea is floating in the kitchen sink. It seems to be working, but I should give it more time. After I post this, I'll go check for leakage and if it's good, I'll tear everything apart to dry the bearings off. I'll take photos to post here at that time.

[Dr. Jet]

Photos

Well, the shaft seals appear to work. There is a bit of drag on the shaft, but it is minimal. It is now ready for testing; all I have to do is wait for the City of Poway to open up the lake. They are currently hiding under a rock trying to avoid the scary Chinese Bat-Eating, Coughing Death Virus.

Now I will reveal my plan and one of the reasons I picked this hull. I plan to do an "Angry Bird" theme: A yellow nose, a red body with some darker red circles behind the "eyes", a light reddish-grey underside, and an eyes/eyebrows decal on the front of the canopy blister.