project 2013: #124 - the very last HPR 233

[ManuelW]

turbine mount system HPR 233 "lightweight"

I think the pictures are pretty self-explaining. Took almost 3 months to get the necessary high-strength and temperature resistant CF sheet. Weight saving compared to the stock part was expected to be huge, around 330g per side. Overall thats 0.66kg or 1.3 pounds! Strength and stiffness should still be on the level of the stock aluminium mount.

regards,
Manuel

[ManuelW]

2S Lipo for supply of turbines

Not a very spectacular chapter. The lipo for the power supply of the turbines arrvied. Its a 2S 5800mAh Zippy 30C Lipo. When fully charged it should enable roughly 6 starts for both turbines before it needs to be recharged. As quite usual on lipos from HK, I will completely change the wiring and soldering done on those. Will be replaced with two 2.5mm² cables for the supply of the ECU's and a 3rd set as charging cables. Plus an additional 1mm² cable which works as cable necessary for the balancer between the two cells. The lipo is with a little PCB at the front which will make soldering pretty easy. Pictures from that work will follow.

There is also an advantage in weight over the stock lipos JetCat delivers with the turbines. 300g vs. 2x 220g, saves another 140g.



drives & rudder

Want to show you my design for the drives (and partly also for the rudder). The drives are completely my own design and custom made, beside the Joint bearing from IGUS and the stainless screws everything else is custom. Took a couple of hours do design everything in the CAD program, many things were changed or drawn new from scratch before it came out as I wanted it. As it can be clearly seen are the drives very long and of rectangular shape. They are almost 1"x1" in cross-section. Also the prop shaft is 9mm diameter instead of the regular 8mm for higher bending stiffness.

Beside that I tried also to get a coherent design of all individual parts. Definitely not everybody will like it, it should look kind of "agressive" and feature some kind of race or high performance look. But only optic is massive, I tried to make these as light as possible. One part mounted on the transom is less than 150g. Almost all parts will be machined out of high strength aluminium, a few will be V2A or high strength steel. If someone is interested I can forward some material numbers.

The rudder design is not finished at these pictures but it shows already pretty well where it goes. Will presented it later when its finished.

For today I hope you enjoy these pictures. By the way the design is not 100% symmectrical, with a careful look you may see some differences between left & right. This is where I tried different things or modifications. The left side shows the final version.

regards,
Manuel










(last pic is definitely my favourite view of the design!)

[iridebikes247]

Manuel without the hatch I imagine you could fit yourself inside the hull? I think a new FE class has emerged haha. Drives look amazing can't wait to see what is the "final chapter," of hpr powerboats done in such an impressive way. Also thank you for responding to my pm manuel I will try the props you recommended.

[Chrisg81983]

Looking sick as usual

[graill]

Keep up the sweetness Manuel, awesome thread.

One thing i do not like is the square drives, while a novel idea and a place to put your name or logo they just dont do it for me.

[nata2run]

Keep up the sweetness Manuel, awesome thread.

One thing i do not like is the square drives, while a novel idea and a place to put your name or logo they just dont do it for me.

I do like the square drives, but to be different I would do this still gives you a spot to engrave something cool.

Drive3angle.jpg

[Chrisg81983]

Look at u go kent get that brain working lol

[nata2run]

Look at u go kent get that brain working lol

Rite who knows...100 years from now??? I might just be????.............................buried LOL

[ManuelW]

Hello Guys,

@ James: Well as already written I was pretty sure that not everybody will like that look of the drives. So I'm completely fine with your opinion. A quote from the german forum is "Was man baut, muss einem selbst gefallen", can be roughly translated as "what you build, has to please yourself" and I'm in love with those drives. And technically I think they are necessary, my aim is still to keep that thing below 50 pounds RTR with fuel.

@ Kent: Interesting idea but I fear they would not work properly on a fast boat. But definitely something new, have to think a little bit more about it.

Here a little teaser I just did because I had the components at home:




Even with the setup in the two pictures above a RTR weight of ~50 pounds should be definitely possible at speeds around 85mph. And with 15.000mAh runtime should be decent, would estimate something around 10 minutes. Well, maybe something for the future.

regards,
Manuel

[Chrisg81983]

That thing is just massive man

[graill]

That was my setup back in 2007 to 2011 Manuel, 12s3p per side, 21 pounds of lipos. The lipos and big lehner 3080's made the boat weigh 65 pounds finished, 72 pounds before I shaved all the weight I could. On medium timing (schulze)you will get well over ten minutes easily as long as you do not goose it a lot, though speed will only be in the 75-80 ish range. Two steps up on hot timing with the schulzes/lehner combo it is scary fast with 12s2p per side the run time was 4-5 minutes not cooking anything, save a cap or two every odd run or so at that level. Enjoy the movement logistics, I did for 4 years, you will find out who your true friends are. I even took it out a couple times alone, doable, but not a good idea.




Trying to get your Turbine rig under 50 pounds with fuel is going to be interesting. Here are my current weights to balance against yours, I am not close to your proposed weight.

Finished, fully painted hull with rams, rudder, drives, with hatch and intakes: 34 pounds
Fuel tanks: 7 pounds 10 ounces total
exhaust ducts: 4 pounds 4 ounces total
Turbines: 11 pounds minus the mounting. Not sure what I will use but it will not be CF as you are doing.
Electronics: 3 pounds (radio box, radio, servos, tele)
Fuel: JetA 7.4 pounds (4.6 liters at .84 kg per liter) total 2.3 L per side. Kerosene is roughly the same but runs hotter .78-.81 kg per liter depending on amb temp.
Heat shieldinging combined: 4 pounds and change. This includes micro louvers, Gold Kevlar heat shield panels, aluminized and graphite barrier (exhaust) and shielding. I should have extra of most Manuel, you pay shipping and I will ship what I have left over once I measure it, I could do that for you next week. Save you some hunting and some bucks unless you are forgoing the heat shields because of weight.

Plus or minus 2 pounds. With your hull being custom reinforced it weighs more than a stock hull to begin with, you are already beginning at a deficit. I think you should target 60-65 pounds myself. Grin.

[ManuelW]

Hi James,

ouch 72 pounds is definitely a little on the high side. The thing is with the turbine I'm pretty limited with power as JetCat even reduced the nominal output at the shaft to 6kW each. Still pretty impressive but today not a huge task to exceed those numbers with enough knowledge and a suitable electric setup. So as performance comes from power/weight ratio and I can't step up in power I'll try to reduce weight. Big thanks already for your list, may even print that out

But don't overestimate the weight of the hull. Sure its an absolute special version with custom reinforcements but weight was definitely a topic beside having a good strength and stiffness. So the bare hull without canopy is just a light 16 pounds. Will save a little on the cut-off tail and the exhaust boxes but have to add some additional resin and weave for the tips and the tunnel seam at the front. With a vaccum bagged sandwich canopy I'm very confident I can keep the weight of the bare unbuilt hull with canopy below 19 pounds, aiming for just 18 pounds!

In a few months we'll know more.

rudder mount

The HPR 233 has the same tail as any other HPR catamaran, just a "little" bit bigger. And the regular rudder fits perfectly. But I wanted to have something special with the modern "mystic style" look. So first I simply cut off the stock tail making a HPR 229 out of it, almost 2" shorter now.





But now how to make something new? Well I had to think quite some time about it. Did already make a similar modification on a HPR C5009 but from the size that was pretty "easy". For such big boats things get a little more tricky. But finally I came up with a solution. First I took some very precise measurements from the inside and finished a CAD design for a part:



Then I had that CNC machined out of 3mm dark black GFK sheet, overall around 18 times (the picture shows not all of them). As you notice most of them got 2 big bores, only two are missing those. This is because these are the top/bottom layers.

[ManuelW]

The idea behind is to stack those up to a thickness of almost 2inch, this is what it looks like:



The six 3mm bores are for the rudder, the bigger bores are now covered and make the stack hollow inside (@ James: every gramm counts ). And finally that full stack will be adjusted inside the hull, fixed with some drops of superglue and then laminated from inside. But for that step I'm still missing the rudder which I'd need for the necessary adjustments.

But to give an idea how that looks here some pictures of a single sheet put inside the hull. I think I can be a little proud, the fit is absolutely precise and gaps are very tight. Definitely already spent a couple of hours on that one, time that nobody would be willing to pay but with things like that I want to make it unique.





regards,
Manuel

[Chrisg81983]

Very intresting man I want to see how that works out

[graill]

That is too wicked Manuel.

Going to have to visit you someday.