My first attemp at 5s with my stock HK Pursuit:)

[boilo56]

I'll try moving the ESC first, i think. ''IF'' it is only what it needs, it will be easier to go back. But i also noticed a bit of torque roll with this motor, i might have to ajust the trim tabs anyway...

[martin]

Apologies all this talk about cg being to far back, I meant one thing but typed another. Of course the cg needs to move forward to keep the front down.

[boilo56]

Thats what i thought!

[Meniscus]

Congrats on you continued progress!

Please keep in mind that partial throttle on any ESC will put much more stress on the ESC which can lead to failure.

[boilo56]

Congrats on you continued progress!

Please keep in mind that partial throttle on any ESC will put much more stress on the ESC which can lead to failure.

Please, tell me how it would be more damageable for the ESC? I thought that if it doesn't need to provide max power, it would generate less heat and run cooler.
I'm probably wrong, but i would like to know why.

Thank You!

[Meniscus]

When an ESC runs at full throttle, it is the most efficient. We all try to keep smooth acceleration and deceleration at all times. Whenever an ESC is not at full throttle, it is not as efficient which is why it generates more heat. There are numerous reasons for this in the electronics that include the way that ESCs generate the pulses for 3-phase brushless motors. Going into more detail, if you take a moment to consider what input the ESC is seeing when you are running at partial throttle, you may realize that the signal from the RX is constantly changing. The ESC is constantly trying to adjust for these changes and at the same time, trying to measure the position of the rotor through the two wires that are not engaged at the time. When you run at full throttle, the signal from the RX changes very little which is one of many reasons why the ESCs are more efficient at full throttle.

The best recommendation is to always try to provide smooth throttle input and prop down if you have too much speed. You will enjoy a longer run time and your ESC will have a much easier job. Those that have employed this methodology often have ESCs that last hundreds of runs without issue or damage. I have several that have seen over 300 runs and they are still able to go out and break records as if they were new.

If you seek more detailed information or are interested in what happens within an ESC to translate DC into pulses for a 3-phase brushless motor, there is a ton of good information on the web and most of the manufacturers provide guidance in their documentation with their products. Hopefully this is helpful and supports the longevity of your electronics. Have fun and try to keep that throttle input smooth.

[boilo56]

Thanks for the info, i'll check for sure, i am the type of person that ''NEEDS'' to know what the meaning for everything... I'm Hungry for knowledge!!!

[boilo56]

Hi everyone! I went to the lake this morning. i was running the X443 cnc prop on 4s. Please look at the video and pictures and tell me what can cause such damages on a prop.https://youtu.be/UVWvLrdosUc

Thank you!

[tlandauer]

Its where the loading areas are----tongues. In my opinion the aluminum is not strong enough and the metal just simply fatigued. I could be wrong though.
The way the boat is jumping in and out of the water, the sudden change in the load means constant " bending" of the tongues of the blades.

[tlandauer]

Not surprised, it's been known that the blades can shear off on the CNC props.

[boilo56]

Not surprised, it's been known that the blades can shear off on the CNC props.

I did not know that! So is this why the hard metal props are better? It was only the second run of that prop!

[tlandauer]

I did not know that! So is this why the hard metal props are better? It was only the second run of that prop!

I am not an expert, but Copper-Berryllium Ti is an excellent material for prop. I have seen pictures of Russian submarine props made with that. it looks just like the props from Grim racer prop ( I mean the appearance of the material).
The advantage of CNC prop is that they don't need too much post-production improvements, they are balanced, all you need to do is sharpen the leading edges a bit. I use it on some boats and I like them. I don't run them in choppy water as you have and may be my RPM is not as high.
Also it is possible that yours came from a less than perfect batch. I have been to TFL's factory in China and saw a CNC machine turning out props, it is an impressive machine but the owner Mr. Ke showed me how every now and then some bad cuts or blemishes will render them useless.

[martin]

Aluminium props are not as strong as bronze props & they do sometimes through blades, I think you hit something. Check the video at 2.16 sec as the boat was upset & jumped out of the water & deflected to one side.

[boilo56]

Aluminium props are not as strong as bronze props & they do sometimes through blades, I think you hit something. Check the video at 2.16 sec as the boat was upset & jumped out of the water & deflected to one side.

I thought it was only the boat not taking the wave correctly... If i would have hit something, i think that most of the blades would have been damaged, not only both tongue... But my knowledge about props is very limited. This is my first real season of FE boating!

[martin]

Personally I would not use these cnc aluminium props, I don't think they are strong enough for the high rpm & loads that are being applied. They are very very thin in section, you can break pieces off of a damaged prop with pliers quite easy.

[boilo56]

Now that i know this, i will only run S&B props... but they are a bit expensive.

[Meniscus]

I have run CNC props successfully on SAW setups, but only under smooth load and no turning. These were also very light builds, so if we take into consideration how easily they can bend by hand with just a little force, it would be better to run one of the other stronger metals.

However, this has got to be one of the most unique ways that I've seen to detongue a prop!

[boilo56]

However, this has got to be one of the most unique ways that I've seen to detongue a prop!

I have to agree with you!