Stepped mono hulls.

[rockwerks]

Why only 3100 rpm/V ?
On 2S, what prop do you have in mind ?

I have several in the 1/8" size and also maybe run a small tranny designed to increase torque and decrease rpm only time will tell what works with this

[Gerwin Brommer]

ah okay, we don't use tranny's overhere.

[rockwerks]

ah okay, we don't use tranny's overhere.

with the use of some car esc's like the monster or mamba max i can also dial in the rpm curve, punch, max voltage applied etc. Its an experiment and does not need to turn well just straight line

[Gerwin Brommer]

Lomdel :

http://www.mbp-rc.de/P1-Micro

[Fluid]

Because stepped hulls are not legal for most racing in the US they are not commonly seen or built here, while in Europe the opposite is true. Where stepped hulls have an advantage is at moderate speeds and moderate power where the high lift/less wetted area helps extend run time and speed - and power consumption is lower as well. These characteristics are of great advantage to most European racers where heats are generally long and available power has been limited. They are also of interest to full-scale mono builders like Fountain, who can get their commercial hulls to go faster with limited power. We cannot really compare model race boats to full-size pleasure boats (or race boats for that matter), we have so much more ‘scale’ power available.

With the very high power we have today steps have limited value. Most European hulls have been designed for 30-50 mph, not competitive in speed to current sprint racing monos in the US. A problem with stepped hulls is that they have a narrow speed range where they work well; this can be changed by modifying the step aoa – lower is better for higher speeds. But this markedly reduces the versatility of each hull. Eventually the speed advantage of a stepped hull approaches zero compared to a non-stepped hull. Plus it is difficult to achieve the same cornering with a stepped hull that you can with a non-stepped hull – the later wins every time with equal setup. With modern power it will be interesting to see what the European designers come up with in stepped boat design over the next few years.



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[Gerwin Brommer]

Jay, you are right, 100%.

One of the latest boats : http://xy-scripts.de/xy/product_info...0f2609adcd180a

[Simon.O.]

I am amazed at the response to this side of my research. Thanks a lot to all of you.

I am going to step my Mono and that is a given. I am not trying to reinvent the wheel or come up with anything new but more to find out why and how certain designs work.
I do this two ways. First I read what i can find and then I ask more specific questions and group the answers to decide if the project is a go.
Secondly I then make a prototype of if I have an existing hull I will make enough alterations so that I can implement changes to the design and evaluate those changes one step at a time.

I did this with my cat as some of you would have seen and I now have a very successful hull (for me) as it is stable and steady at just over 40 mph with the new steps. This took a lot of time and a lot of work.
For me it is very satisfying as I now know a bit more abaout how steps work through on water experience.

I learnt a lot from that project and will implement some of those design / build ideas into the new project.

I will now move the main thrust of this discussion over to the hull that will be stepped.
Here.
http://forums.offshoreelectrics.com/...ad.php?p=97944

[ED66677]

Jay (Fluid) is right, as always
to me Europeans use stepped hull because it is easier to fine tune, lazy we are , I've not too much experience though, but after watching ton of videos from frenchies make me feel that I made the right choice with my DF copy, way more stable!

[Brod]

Also i think most European racers use stepped hulls because most come with a built in flood chamber(selfrighting) which is almost a must for the frantic 6+ boats in a heat race.
I run mostly Delta force type hulls and when flipped its game over..
Brod..

[Gerwin Brommer]

Brod :

Why not make a floodchamber in the DF ? It's easy to do.