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Thread: Prop recommendations - Different pitches & diameters, plus 2-blade vs 3-blade

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    Default Prop recommendations - Different pitches & diameters, plus 2-blade vs 3-blade

    I'm not entirely certain of the best way to word my questions...or even how, specifically to ask them, so pardon if this seems like a "jumbled mess". Adding confusion to the c chaos, this isn't related to any one specific boat - these questions could be applied equally to a monohull, a cat, a hydro, or outrigger. In my case, right now, this relates to three different boat of two different types (mono & cat), and two different motor/prop configurations (single & twin). Anyway, here goes nothing.....

    To start, I'm going to ignore the 2- vs 3-blade part of this mess, as that would probably mess with people's minds too much...as I've been known to say, "Start easy, then go hard." Assume the same motor, ESC, and battery for all possibilities, and assume that the motor & ESC are more than capable for all possibilities. In regards to diameter & pitch, I'm going to first toss out a couple of 'pairings':

    1715 vs 1814
    1716 vs 1815
    1716 vs 1814

    For these pairings, think of them as all 2-blade and/or all 3-blade combos. Just looking at these combos, in terms of speed, stability, and any other points you might think of, what might be the advantages/disadvantages of each over it's "paired partner"? Also, how would power draw, and ESC & motor temps, be affected? For each pairing, which prop would you prefer, and why? If there's any noticable difference, of each pairing, which would be better for racing (where speed AND controllability matter), which for just 'having fun' (where stability is more important than speed), and which would be better for all-out speed runs?

    Taking things up (or down, depending on how you look at it) a notch...now we get into the 2-blade vs 3-blade...here's a few more parings to consider:

    1716 2-blade vs 1715 3-blade
    1815 2-blade vs 1814 3-blade
    1815 2-blade vs 1715 3-blade

    For these pairings, the same questions apply. I'm still in the somewhat early in the learning stages of FE, but I think these questions, and the answers to them, could help veterans & newbs, alike.

    Yes, I could have selected any number of props...but, in my attempt to keep this as incomplete as possible, I chose to limit the props to just these four diameters/pitches. As readers gain more understanding of the interaction between just these four, we should all be able to apply what's learned to other diameter/pitch combos.

    Let the games...and gain in prop knowledge...begin.


    ~ More peace, love, laughter, & kindness would make the world a MUCH better place

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    Dig around in the forums to find the answers you're looking for

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    Hi Panther,
    In short you can start here. A smaller prop at the same pitch will have the potential to be faster as there is less drag. The convo if engaged fully will go all over the place. Its ALOT to talk about. It also WILL have to depend on the boat as far as thrust cones etc are considered. Some larger lower piched prop just do better on some boats. The other thing to considers is the load it puts on the motors. Lohring looked and determined increase in load was more a proponent of diameter vs pitch. That's another angle to consider. Then you have the rake and what it does with the bow of the boat. Raise it or lower it. This is one of those 20,000 view threads. Ill likely bow out before it begins really coz the debates will go on forever. I have the newest works on supercavitating propeller profiles and Its a great source of information about SP props.I think Ill share just that and run for the hills.... If you want everything I got which is alot Pm me.


    Regards
    Hubert,

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    Quote Originally Posted by Panther6834 View Post
    I'm not entirely certain of the best way to word my questions...or even how, specifically to ask them, so pardon if this seems like a "jumbled mess". Adding confusion to the c chaos, this isn't related to any one specific boat - these questions could be applied equally to a monohull, a cat, a hydro, or outrigger. In my case, right now, this relates to three different boat of two different types (mono & cat), and two different motor/prop configurations (single & twin). Anyway, here goes nothing.....

    To start, I'm going to ignore the 2- vs 3-blade part of this mess, as that would probably mess with people's minds too much...as I've been known to say, "Start easy, then go hard." Assume the same motor, ESC, and battery for all possibilities, and assume that the motor & ESC are more than capable for all possibilities. In regards to diameter & pitch, I'm going to first toss out a couple of 'pairings':

    1715 vs 1814
    1716 vs 1815
    1716 vs 1814

    For these pairings, think of them as all 2-blade and/or all 3-blade combos. Just looking at these combos, in terms of speed, stability, and any other points you might think of, what might be the advantages/disadvantages of each over it's "paired partner"? Also, how would power draw, and ESC & motor temps, be affected? For each pairing, which prop would you prefer, and why? If there's any noticable difference, of each pairing, which would be better for racing (where speed AND controllability matter), which for just 'having fun' (where stability is more important than speed), and which would be better for all-out speed runs?

    Taking things up (or down, depending on how you look at it) a notch...now we get into the 2-blade vs 3-blade...here's a few more parings to consider:

    1716 2-blade vs 1715 3-blade
    1815 2-blade vs 1814 3-blade
    1815 2-blade vs 1715 3-blade

    For these pairings, the same questions apply. I'm still in the somewhat early in the learning stages of FE, but I think these questions, and the answers to them, could help veterans & newbs, alike.

    Yes, I could have selected any number of props...but, in my attempt to keep this as incomplete as possible, I chose to limit the props to just these four diameters/pitches. As readers gain more understanding of the interaction between just these four, we should all be able to apply what's learned to other diameter/pitch combos.

    Let the games...and gain in prop knowledge...begin.


    ~ More peace, love, laughter, & kindness would make the world a MUCH better place
    I consider myself a noob. What is the question you are asking in this wall of words? Stop beating around the bush and just get to the point. I run 1716 props on my Zelos twin 36 . But for the life of me I can't tell where you are going with this thread.

    And as a noob I'm pretty sure hull design does factor in on prop choice depending on motor size and battery size choice. Some where on this forum there is a post all about Props and prop design. Maybe you should try and find it . Honestly It was more info than I'm interested in. I don't intend to design props . I would rather leave that to the pros. I can give them my specs and then I can work with them on tweaking the props to dial them in to what I'm looking for and want my boats to do. Good luck

    I know I'm coming across as rude or hostile but it's because I don't understand the point of this thread. Sorry

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    Come on now he can inquire if he has a deeper interest. That's not against any rules and the other thread may not encompass his inquiry. Its totally all right. Don't get upset about it. Not at all trying to be offensive but if you are a self proclaimed newb why not sit back and see if there's something useful for you here? If you are not interested certainly he can still be. Right? Obviously there's alot of things I don't understand about peoples behavior on public forums but this thread certainly isnt one of them. Ironically your post is what I don't understand. Sometimes I think we forget we're in free society.....supposed to be anyway. It could be the fact that you haven't come into the fold that you dont understand what he's after. I admit he wont find it on the pages, it will be on the water, but it's a good topic to get a healthy discussion going about an aspect of boating many of us do have interest in. Why should a forum be dominated and controlled by people who know the least? That also makes zero sense. And again I only use your self proclamation to judge you u could be an expert for all I know. No slight intended. If all we did is refer back to old threads then we may as well archive the forum and leave. Every topic that will be discussed into the future has already been discussed in the past, but realize new developments in the understanding of propellers continues to fall from academia and empirical measure, so please don't stand in the way of technology and people's understanding of it. America has got enuf idiots already that don't know anything. That's why we losing AT THE TRAPS TOO! Whats wrong with you guys? Y'all dont like talking about rc boats?You just like looking at them and running them and give a rats you know what how they work? That's what I don't get. How did the prop experts become that? What happens when the current ones are gone? Do young people realize they should gravitate to knowledge vs excess. Buying a bunch of hulls that don't run worth squat. you supposed to take these torches and run 300 mph by 2050 and beyond. Most of us will be gone. Wake up people. Have an interest in learning. IT'S FUN!

    Regards
    Hubert
    Last edited by eXoNerated; 07-01-2020 at 09:21 PM.

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    Quote Originally Posted by eXoNerated View Post
    Hi Panther,
    In short you can start here. A smaller prop at the same pitch will have the potential to be faster as there is less drag.

    The other thing to considers is the load it puts on the motors. Lohring looked and determined increase in load was more a proponent of diameter vs pitch. That's another angle to consider.
    First. I'm not getting what you said first. If you have two props of the same pitch, and different diameters, how can the smaller diameter be faster? Doesn't the larger diameter prop push more water? Wouldn't that mean the larger diameter should be faster? Obviously, in this, I'm not referring to some "huge diameter difference". If you look at the diameter/pitch combinations I mentioned in my 'samples', you'll notice that they only vary by 1-2mm. If the difference were huge...say...32mm & 40mm, I would understand the "drag" you mentioned, thus the 32mm could easily be faster (on the same boat). But, if dealing with...say...32mm & 34mm, the drag increase should be very minimal, thus we'd be back to the fact that the 34mm prop pushes more water than the 32mm...right?

    As for the "load", that's actually pay off why I brought the topic up, and why I decided to only list a few combinations. The diameter/pitch variations within each pairing are minimal enough that I was curious how speed, as well as motor-load would be affected. Also...I'm not starting the pairings as if they were on two different (say, V vs cat) boats - for each pairing, assume that both props would be installed on the same boat, no matter what that boat might be.

    I didn't create the thread to specifically help me...I created it for all. People, myself included, are always interested in knowing how a 'change' will affect things like speed, handling, and motor-load. For newbs, this is even more important. I created the thread so that those "in the know" could present the info in simpler-to-understand ways, so that all...newbs, and "salty dogs", alike, might gain knowledge. As you said, yourself, the industry is constantly changing, and even those who know a lot (in regards to 'old' technology) still learn...especially when it comes to 'new' technology.

    Every "pairing" will affect a boat differently. Using just one combo ..say, 1715 vs 1814...as an example, these two will, obviously, have different effects...but, my 'query' was more about "how". For example, just using these two props, would one be faster (and which), would one create better handling (and which), and would one put a greater load on the motor (and, once again, which)? In this, it's not really about the "boat", but about the 'differences' between the props in any pairing.


    ~ More peace, love, laughter, & kindness would make the world a MUCH better place

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    If speed is pitch times rpm but one has less drag why wouldn't it be faster?just think about it for a minute. They have the same pitch. Thrust is a proponent of slip not speed. Ie a tug boat has more thrust than a speed boat and alot of slip but it isnt fast . Typically SAW fe is smaller diameter large pitch props. There is no way here to tell u exactly wat will happen there are too many variables. At least for me. When I comes to props empiracle evidence reigns Supreme. Even the temp of the water makes a difference. Typically the larger blade area wiil the higher the load at the same rpm. Faster would be faster by a 10 mph difference or a half mile an hour one. That should be enuf to point to minute differences in drag . The other thing to consider is the AR. Or aspect ratio. That's the XX14 ...XX15 you see at the end of the ABC's Typically higher AR generates more lift so now you have to consider the hull and whats appropriate for its running attitude. From this its probable the 1.5 AR has more lift than the 1.4 but it would be minute if the leaf is basically shaped the same.

    Regards
    Hubert
    Last edited by eXoNerated; 07-02-2020 at 07:21 AM. Reason: th

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    The simple NOOBY answer in my experience (40+ years) is understand what you are working with. I find it easiest to figure out each prop diameter and pitch in millimeters. Octura's are easy. X450 or 1450 different blade designs but 50mm diameter times 1.4 pitch ratio. 50X1.4=70mm pitch. ABC uses inches and pitch ratio 1814 is 1.8" X 1.4 pitch ratio - 1.8 X25.4 = 45.72mm so to simplify round up 46 X 1.4 = 6.4.4 (65)mm 1914-48X1,4=67mm 1915 -48X1.5=72mm. Simple calculator(on your phone). This is just basic. Then comes the fun, blade area, blade rake, blade style, progressive pitch, trailing edge cup?
    Now realize every hull needs X amount of blade area to push or thrust the boat to an efficient speed. Bow lift, tail lift, angle and height of strut come into play. For a noob either buy and try different props and do adjustments or have your favorite prop guy recommend and cut props for you. Trial and error will increase your knowledge.
    As for 2 or 3 blade I like 3 when possible but bear in mind 3 blades have more area to push and have 50% more cutting edge drag. That said in general less diameter and pitch going to 3 vs 2 blades. A 3 blade has less tendency to be a paddle on a surface drive.
    Try all the props you have and can borrow within pitch ranges you find that work on your hull. Be careful going too far up in diameter as load increases more than with pitch.
    Mic
    Last edited by HTVboats; 07-02-2020 at 10:25 AM.

    Mic Halbrehder
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    Thanks, Mic. Now, that's a reply that makes a bit more sense, and one that people...newbs & old timers...can understand.


    ~ More peace, love, laughter, & kindness would make the world a MUCH better place

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    Quote Originally Posted by eXoNerated View Post
    Come on now he can inquire if he has a deeper interest. That's not against any rules and the other thread may not encompass his inquiry. Its totally all right. Don't get upset about it. Not at all trying to be offensive but if you are a self proclaimed newb why not sit back and see if there's something useful for you here? If you are not interested certainly he can still be. Right? Obviously there's alot of things I don't understand about peoples behavior on public forums but this thread certainly isnt one of them. Ironically your post is what I don't understand. Sometimes I think we forget we're in free society.....supposed to be anyway. It could be the fact that you haven't come into the fold that you dont understand what he's after. I admit he wont find it on the pages, it will be on the water, but it's a good topic to get a healthy discussion going about an aspect of boating many of us do have interest in. Why should a forum be dominated and controlled by people who know the least? That also makes zero sense. And again I only use your self proclamation to judge you u could be an expert for all I know. No slight intended. If all we did is refer back to old threads then we may as well archive the forum and leave. Every topic that will be discussed into the future has already been discussed in the past, but realize new developments in the understanding of propellers continues to fall from academia and empirical measure, so please don't stand in the way of technology and people's understanding of it. America has got enuf idiots already that don't know anything. That's why we losing AT THE TRAPS TOO! Whats wrong with you guys? Y'all dont like talking about rc boats?You just like looking at them and running them and give a rats you know what how they work? That's what I don't get. How did the prop experts become that? What happens when the current ones are gone? Do young people realize they should gravitate to knowledge vs excess. Buying a bunch of hulls that don't run worth squat. you supposed to take these torches and run 300 mph by 2050 and beyond. Most of us will be gone. Wake up people. Have an interest in learning. IT'S FUN!

    Regards
    Hubert
    Generally when I want to learn something I ask a direct question. From there I'll ask others if something doesn't make since to me. I'm an Manufacturing Engineer so that's my excuse plus I had had a couple beers last night and just found the post frustrating . Carry on.

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    Quote Originally Posted by 1coopgt View Post
    Generally when I want to learn something I ask a direct question. From there I'll ask others if something doesn't make since to me. I'm an Manufacturing Engineer so that's my excuse plus I had had a couple beers last night and just found the post frustrating . Carry on.
    Glad to hear you're a "manufacturing engineer", and not an English teacher, as there's no excuse for poor spelling and/or grammar.


    ~ More peace, love, laughter, & kindness would make the world a MUCH better place

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    Let me break the ice and stay on topic while I still remain. Could one of the "experts" tell the forum what we are looking at here? Let me see where you at about a prop.

    Attached Images Attached Images
    Last edited by eXoNerated; 07-02-2020 at 08:55 PM.

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    Wow it sure looks like "empiracle evidence" to me.

    Mic Halbrehder
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    Does it look like that's what "it " is 1coopgt ? I can assure you Jim S (ABC) the makers of these props they are discussing does. Send the attachment to him to get an answer.

    See.....let it go. Let the discussion run it's course because maritime engineers know that most everything about a prop isn't learned in competition setting. Perfection of propeller design require incredible math! There's no way these calculation would be done anytime soon without discrete analytic tools that are verified through models and "empirical" comparison. Academia always does that that's scientific process. Engineers are familiar with the practices I don't have to explain this to you. They never use one data set to make conclusions from. Those are the notions of those not involved at this level. Simple as that. Firstly you still haven't been told what it is yet. If you are truly at a prop you should at least have a clue. Trial an error is great and useful but it isn't exacting enough to consider it a broad knowledge status of "prop expert". To me it means exactly what it is I found the good prop for my boat by trying everything BUT I still don't know why it ended up being the best prop. That answer cannot be found the water so there's a dilemma here for anyone that thinks that. Enjoying the thread carry on. AND REMEMBER JUST LIKE YOU SEE IN YOUR QUOTE "NONE OF IT WILL BE FOUND ON THESE PAGES"

    Some of us haven't fully read all the post b4 making cute comments

    But its all good. I told you so.... what good would a true guru be if his information is totally incomprehensible by a newb? they don't speak the language of old timers who know anyway. Let him have what he wants. The obvious.... Ask for information then slam the deliverer of it. That's wonderful I said things that didn't make sense but it's valid.

    The empirical is what panthers is after but "empiracle" doesn't pass his grammar test. I'm certainly no grammar teacher but most time I can spell or notice the red line beneath. LOL

    Reading with great interest. I agree with you now. If he wanted a "specific" answer merely to concur with his own thinking it isn't an honest thread. He shoulda asked. I agree.

    Regards
    Hubert
    Last edited by eXoNerated; 07-03-2020 at 11:27 AM.

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    Quote Originally Posted by eXoNerated View Post
    Does it look like that's what "it " is 1coopgt ?


    Hubert
    You're asking the wrong person. I've no clue and apparently I've offended an English teacher. Carry on

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    Oh I'm def done but your post is refreshing enough. At least your honest, can spell, and kept your mouth closed because you did not know. I know you didn't make the comment but there is no need to address people that place no value in exacting science. Trail an error with no definitive initial direction or solid understanding of how they work from a physical sense, just isn't how I do things. Different strokes......

    Without you knowing at least you can speak the language and value physical science. As an engineer I don't see this vast divide between theory and "empirical" evidence. To me empirical evidence is the information you gather when you remove the theoretical model from his controlled lab environment into an uncontrolled one with many variables, like water temp., density, etc. I spoke to that 1st but he couldn't understand it the way I told it to him. But its all good. I don't explain things a simple way simply because I'm not simple minded. Most times the optimal theoretical model still ends up being the best one to introduce to the empirical environment. isnt that the point of science

    Regards
    Hubert
    Last edited by eXoNerated; 07-03-2020 at 12:10 PM.

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    I don't make any claim on being an expert. I do race and have been to record trials. So without an engineering degree (my college days were interrupted by the Marines and a trip to Viet Nam) I do know who Bernoulli is and what the shape and affect trailing edge water breaking off a prop does. Also you can affect pressure on the face of the blade with the TE shape and cup. I know a few guys who can take a pliers, bend some blades, and totally change how a boat runs. I bend some from time to time also but don't have the "black art" down.
    I was testing motors this week on a "mule" (boat with known parameters) and with two different props. The motors are for a twin and I wanted to make sure they were close in watts. After seeing they were very close I looked at the slower prop which was cavitating getting on plane. So I cupped the tips (hammer and SS ball) not precision and went from 55 to 63mph. Amps went up from 170 to 220 and watts 2600 to 3300. Rpm dropped from 27000 to 24000. So trial and error with a bit of experience does pay off.
    As I stated before know pitch and diameter and keep track of how it affects your boat. From there learn blade profiles and rake. Use good data loggers and GPS's that do more than give top speed
    .72 mph 1817 38.jpg.
    I don't do much with SAW runs antmore but do know my corner entry and exit speeds. I test off my dock quite a bit and keep a log book with info like amps, rpm, watts, speed, temps, motor and battery used, run distance and end voltage. I run mono's, hydro's, cats and OB tunnels.
    No formal degree so I can't say the knowledge of vapor cavity shape or distribution will help me. I must be a failure. Oh yeah check the NAMBA and IMPBA record books, you might see my name or my son and grandson.
    Mic

    Mic Halbrehder
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    Nice resume MIC. I know all about it already. Have fun with your tunnels. They are fast. You've come a long way in "FE" the last few years. Do you think that is that because of the PROP you run being so much better than everybody elses or can you actually drive and have a decent setup on your boats? That's not the same thang ya know..... Do you prepare you own props? What do you do that's special with them then?

    THESE WOULD BE JUST SOME OF THE REASONS YOU EXAMINE THE PROP IN THE CONTROLLED ENVIRONMENT AND NOT THE ENTIRE VESSEL AND ALL THE OTHER VARIABLES A COMPETITIVE RACE WOULD ENTAIL . NOW THE OP CAN CHANGE HIS MIND BUT THE TOPIC WAS PROPS NOT COMPETITION TUNNELS AND THE BEST PROP FOR THEM

    Theres no black art to ABC 's prop design. He uses MEF. Maritime Engineering Fundamentals



    Regards
    Hubert
    Last edited by eXoNerated; 07-03-2020 at 01:52 PM.

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    Black art is when someone that knows nothing about it but through empirical evidence of trying everything or plain luck they found something that worked. Many times they cannot tell you why if they did not have some right or wrong theory in their head, and approached it in incremental steps under that premise taking notes. Otherwise they can't really tell you WHY it works and thats what makes it so called a black art. Nah fam there's def people that have a good idea of exactly what to do without running the boat or being the driver. JS(ABC) is one.

    Regards
    Hubert

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    And then why does it always come to this between theorist and empiricist? Here's the difference between the two. An empiricist may say remove material "here" and "here" from a prop because when I did it was fast. The theorist or "Thinker" would possibly use the information in the attachment to determine exactly where to remove material for the best surface piercing super cavitation performance. Where they may consider things like leading edge flutter. The empiricist may run into a snag at some point. A wall in which he cannot increase his performance. He cant see through racing what's happening now.So he becomes dogmatic and now he's surely done because what he saying may be or may not be correct. The other problem is it usually takes the empiricist much longer to arrive at the same level of performance as the theorist/empiricist.

    Regards
    Hubert
    Last edited by eXoNerated; 07-03-2020 at 02:24 PM. Reason: Horrible grammar still horrible

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    Hugh just keep talking, you're good at the keyboard. So what races have you actually run? Let alone show up and prove your great knowledge. Been waiting since you spouted off in 2012. Still no Hugh sightings. You keep name dropping. AB JS JA like your one of the boys. Until you actually do something off the keyboard your just a "troll". How many forums have you been banned from? You will post again as you always have as you have a need to get the last word in. Panther who started this now epic Hugh babble thanked me for basic knowledge and you just spew things you feel make you superior. Sorry Panther.
    Mic

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    I wont go there with you Mic it's nothing "personal" . Just talking about the props buddy is all.

    Regards,
    Hubert

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    Mic Halbrehder
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    Hi Mic,
    thanks for you wise words, we know from IW .
    @Panther6834,
    i try to bring some understanding into the context. But it doesn't necessarily have to be that way, I don't know your boat and not all components of the drive.
    The smaller two-bladed propeller that has the same slope as the slightly larger three-bladed propeller can make the boat faster for the following reason. The small propeller puts less strain on the engine and therefore the speed will be higher. Even with the smaller two-bladed propeller, the higher speed can pass through the same amount of water as the larger but lower-rotating three-bladed propeller. The thrust would be about the same. If the boat is still running in a speed range in which the resistance is not very high, then the higher speed can be converted into a higher top speed with the same gradient. The braking effect of the boat does not seem to brake so that there is no more speed increase. This is actually a very good sign for the boat as it also converts small but faster propeller flow into speed. In the oval race, however, the three-bladed propeller can accelerate out of the curve better due to its additional propeller blade and thus arrive at the next bend a few feet before the two-bladed propeller. Do you still know Ed Fischer's Circus Circus Cannard? That was e.g. a boat that did not drive the highest speed on a straight line for a long time, but in the curves the boat has first been driven around the buoys on the inside and has lost little speed. This led to the fact that it was almost unbeatable at the RC racing boat races and was only taken out of the races by exile. You just have to experience and test and test these things, you can't get around. As Mic wrote, even small changes to the propeller themselves make very big differences in what makes lift, thrust, propwalk and smoothness. It doesn't help if you have installed the best propeller according to the latest knowledge of fluid dynamics on the boat, but then the boat jumps around like a billy goat and cannot build a proper thrust at all. Then there is the knowledge of experienced boaters who then make the boat more drivable and faster. You have to work hard to achieve that. The cupping of the propeller blades accelerates the current at the tear-off edge and makes the propeller reach faster in the water, usually you get a better acceleration of the boat. If you give the propeller blades a little cupp on the outside, i.e. on the cutting edge almost entirely on the outside, the boat is reduced in the lift and it does not jump with the stern.

    Happy Amps Christian
    Happy Amps Christian

  25. #25
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    Nov 2014
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    Hi Panther6834,
    one more thing . I often just stood by the sink in the kitchen and turned on the tap, so a strong jet of water comes out. Then I took a piece of aluminum sheet and held it in the beam and then used pliers or a hammer and various steel balls or other rounded solid steel parts to bend in various curves. The cutting edges are ground and bent and so on. You can clearly feel with your hand what creates a little more distraction and what doesn't work so well. Simply hold a normal spoon in the water jet. The outside does not exert much force and thus directs the beam around the curve, which is simply not a good thing. The hollow spoon side, on the other hand, generates a lot of distraction force and you can deflect and steer the water jet much more violently than with the outside. Everyone has certainly played it that way somehow. But if you take a closer look and observe what the water does, these are very important findings that help you a lot in improving the drives and the boat itself. Tomorrow I'll take a picture of the tread of one of my 1:12 hydroplanes that won some races, although I didn't always have the batteries with the highest energy content. The boat just runs quite easily.
    Happy Amps Christian
    Happy Amps Christian

  26. #26
    Join Date
    Apr 2020
    Location
    CA
    Posts
    144

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    Quote Originally Posted by Ch.Lucas View Post
    Panther6834,
    i try to bring some understanding into the context. But it doesn't necessarily have to be that way, I don't know your boat and not all components of the drive. he smaller two-bladed propeller that has the same slope as the slightly larger three-bladed propeller can make the boat faster for the following reason. The small propeller puts less strain on the engine and therefore the speed will be higher. Even with the smaller two-bladed propeller, the higher speed can pass through the same amount of water as the larger but lower-rotating three-bladed propeller. The thrust would be about the same.

    If the boat is still running in a speed range in which the resistance is not very high, then the higher speed can be converted into a higher top speed with the same gradient. The braking effect of the boat does not seem to brake so that there is no more speed increase. This is actually a very good sign for the boat as it also converts small but faster propeller flow into speed. In the oval race, however, the three-bladed propeller can accelerate out of the curve better due to its additional propeller blade and thus arrive at the next bend a few feet before the two-bladed propeller.

    Happy Amps Christian
    Thanks for the info...definitely helpful (again, for me, as well as for others in need off this type of info).

    Since you mentioned it, and worded it in such a way as to appear actually interested in knowing, here's my current lineup:

    Atomik Barbwire 3 (upgraded to Seaking 60A ESC & Dynamite 8-Pole 2950kV outrunner motor, on 3S)
    ProBoat ShockWave (my "rescue boat", so no need to change props)
    ProBoat SonicWake (currently running stock electronics, but soon to be running Seaking 180A ESC & Leopard 3674 1400kV motor, on 6S)
    ProMarine Skater X2 (dual Seaking 120A ESCs & ProMarine 3674 2075kV motors, on dual 4S) - for NAMBA P-open
    TFL Pursuit carbon fiber (Seaking 180A ESC & SSS 3656 6-Pole 2030kV motor, on 4S) for NAMBA P-Open

    You'll probably notice that the SonicWake's "upgrade" motor is actually less than the stock motor. I'm currently running the stock motor on 4S...but, in swapping the ESC & motor, and moving up to 6S, I'm not trying to make the boat faster - I'm trying to make it run cooler (meaning, the electronics), and give it a longer run time. If it happens to be faster (than the stock electronics on 4S), that's a 'bonus'...but, it's not a "requirement".

    No later than next March, I also plan on adding a TFL Zonda to the collection, although I'm still debating which version to get: the fiberglass, the all-carbon fiber, or the carbon/Kevlar. This one probably wouldn't be for racing, as the only class (as far as I'm aware) it qualifies for is is S-SAW, which they don't run in District 9 (again, as far as I'm aware). Whether sometime this year, or sometime after getting the Zonda, I'd also like to add a race-capable hydro to the lineup...although, I haven't yet decided if it will be a commercially-available boat (such as the ProBoat UL-19), or something custom-built for me.


    ~ More peace, love, laughter, & kindness would make the world a MUCH better place

  27. #27
    Join Date
    Feb 2019
    Location
    NY
    Posts
    81

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    Quote Originally Posted by Panther6834 View Post

    I also plan on adding a TFL Zonda to the collection, although I'm still debating which version to get: the fiberglass, the all-carbon fiber, or the carbon/Kevlar. This one probably wouldn't be for racing, as the only class (as far as I'm aware) it qualifies for is is S-SAW, which they don't run in District 9 (again, as far as I'm aware). Whether sometime this year, or sometime after getting the Zonda, I'd also like to add a race-capable hydro to the lineup...although, I haven't yet decided if it will be a commercially-available boat (such as the ProBoat UL-19), or something custom-built for me.


    ~ More peace, love, laughter, & kindness would make the world a MUCH better place
    After watching MRMAD2424 hit 111mph with a stock(other than Dasboata Props) fibergass TFL Zonda I decided to add one to my collection. Now I wait. What stinks is there isn't a lot of info on this boat in the forums. It's been out since 2013. You would think there would be all kinds of information in the forums about this boat .

    Sorry for the subject change/ highjacking . I couldn't resist when I saw you were thinking about a Zonda. I'm also building a 1/8th scale Hydro.
    Last edited by 1coopgt; 07-03-2020 at 08:40 PM.

  28. #28
    Join Date
    Jun 2020
    Location
    NC
    Posts
    233

    Default

    @ Lucas the persistent troll who's every thread gets banned in Germany.

    There's no wise word from IW just more of your gang violence and silly unfinished projects and dead end threads. Will you be a man stop lying and grow up? These papers I looked up at university of Florida here in the USA. What one you author
    All you did is showed me a 5j profile in a page in a book online. That post can be brought in but I don't care really I just wish you'd get off the sunk sofa in Bayern and stop harassing F3S pilots in Germany and me here in the USA. You turned out to be a real enigma. Jim showed me things u never did and you spoke on what you knew but I sought a million times more information on my own than any man has ever taught me PERIOD u can keep talking but you aint saying a thing true. That's why the most recent literature on super cavitating props went from me to you. I don't know why you keep bringing up Jim you met him thru me. He has nothing to say and cares less about this or you. And why would I need you or any other man to do my own trig? Get lost your trolling hard. If you have so much time complete a project and stop playing in the pool. Jim will tell me anything I wanna know anytime and you are not really his friend . You are very immature and hadn't run a boat in 30 years. Jim like me has logged time on the water in this millennia when will you? Jags was right you are a "F-wit". Jim Schaefer and I have shared many emails over the years. You have a special power and know what people you never met in your life do. Its freaking amazing. You must sit in my pocket, a portable bobble head, so insecure about yourself you have to sit here and lie online. ABC saw no need for a 5 Johnson profile to run SAW. The one you learned out of a book just like me. That's how far that help went and is applied to any boat I have. Zero it's Mystic! Apply it to your own boat this year why don't you. I maintain 2 million dollars worth of 7 axis fanuc paint robots with estat paint applicators for Mercedes Benz as well as a 1/4 of the entire plants automation line BY MYSELF. These robots paint 153 buses and travel on the 7th axis rack 10 kilo meters every three days I DON'T NEED U YOU FOR S*%T and never did you need to get that clear Gibroni! MAKE A WAY BACK TO BAVARIA!

    Transfer efficiency improvements, Day tank automation commission, waste recovery refinements. Positive displacement pump rebuilding. I'm the spearhead pimp! When you hire me? And when you teach me this? NEXT YEAR when I HIT E3 I WONT HAVE TO PAY FOR MY GT OR THE GAS!

    Christ, GET A LIFE!
    Hubert
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    Last edited by eXoNerated; 07-04-2020 at 01:21 AM.

  29. #29
    Join Date
    Jun 2020
    Location
    NC
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    233

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    What are the moderators going to do ? Hes been braking the rules for awhile now and you can see that I've clearly tried to maintain a sense of civility and even left his thread totally alone, but this old ass fool in Germany who thinks hes graduating genius men in the US is really staring to get on my damn nerves! I don't know what educational value the forum finds in his bs ad hominem but I don't find any in it. Whens it stop?


    Regards
    Hubert
    IMPBA 20779S
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    Last edited by eXoNerated; 07-04-2020 at 01:33 AM.

  30. #30
    Join Date
    Apr 2020
    Location
    CA
    Posts
    144

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    Quote Originally Posted by eXoNerated View Post
    What are the moderators going to do ?
    Say what you will, but Lucas is one of only two people who've commented with something that actually makes sense (the other person knows who he is, as I PMd him directly)...and, you are, most definitely, NOT one of the two I'm referring to. You drone on & on, without ever saying anything meaningful. You've spouted off a bunch of double-talk, workout ever saying anything of importance that's truly relevant to the queries I posted. I never asked for "empirical evidence", or any scientific proof. If you had even the most minute ability to comprehend what I was inquiring about, you would have realized I was strictly talking about REAL-WORLD use. Your comments have been disruptive...and, quite honestly, have been a waste of space.


    ~ More peace, love, laughter, & kindness would make the world a MUCH better place

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