Russian Alfa Class

[redboat219]

Most common rule is propeller diameter = brushed motor can diameter.

[rwtdiver]

Another question on my Alfa 1:96 scale build!

What size drive motor (propulsion) in a brushed motor, (I am using 3s 11.1volt lipo battery) would be recommended?

Rob
"Firemen can stand the heat"

[rwtdiver]

For drawing in water, I do not think it makes a difference. I place my inlet near the bottom to allow draining on the bench, but it depends on if that makes the most sense with all the other devices. Sometimes in the center just is easier for piping. The thing that is important is the inlet needs to be large enough to move the water the piston pushes. In other words, if it ia too small the piston will push, but there will be a lot of resistance because the water cannot get out quick enough.This will cause the motor to work harder than it needs to.

If I understand you correctly Tom, it's more important that the inlet/outlet opening is large enough to move the water in and out to create less resistance than where the opening is located!? I understand your point!
I think I will leave the opening where it is located (center of tank) at this point. I will install a fitting that will give me at least a full 1/4" ID for water movement!

Thanks Tom, I appreciate your expertise!

Rob
"Firemen can stand the heat"

[trout]

For drawing in water, I do not think it makes a difference. I place my inlet near the bottom to allow draining on the bench, but it depends on if that makes the most sense with all the other devices. Sometimes in the center just is easier for piping. The thing that is important is the inlet needs to be large enough to move the water the piston pushes. In other words, if it ia too small the piston will push, but there will be a lot of resistance because the water cannot get out quick enough.This will cause the motor to work harder than it needs to.

[rwtdiver]

I have another question?



Does it make any difference if the water inlet is in the center of piston tank or if it is located near the bottom of the tank! I have seen some tanks where the water inlet/outlet is located nearer the bottom of the tank! Just don't know if it would draw in more water from the bottom or if it does not make any difference!? Any thoughts would be appreciated!

Rob
"Firemen can stand the heat"

[rwtdiver]

Thanks Romel,

Great information! I will make a copy of this and use it from now on! May go back in and edit the two videos I just posted! Thanks again for the help!!

Rob
"Firemen can stand the heat"

[redboat219]

[rwtdiver]

Here are the two YouTube videos that I have up on the operation of the piston tank! Videos showing the water in and out operation!

https://www.youtube.com/watch?v=cK5MRR3OCro

IMG 3857 3 - YouTube

Sorry about these videos are from my YouTube channel, I still have not figured out how to get them up on our forum!!

Rob
"Firemen can stand the heat"

[rwtdiver]

I completed my scratch built Ballast Piston Tank for the 1:96 Scale Alfa today! As I have said before, both my Alfa boats are and experiment as far as the ballast systems go!!



I will be posting a small video of the pump in operation shortly!

Rob
"Firemen can stand the heat"

[rwtdiver]

Thanks Steve!

Still have some engineering and build work to do! Not sure if all this is going to work or not. So far so good!

Rob (Still a crazy old man)
"Firemen can stand the heat"

Subculture,

Thank you for chiming in! I see your point! I may have about 4 times the tank volume and not much more! Question: Would it be possible to install and extend a snorkel tube up and into the mast to release the air pressure from inside the WTC?

Rob
"Firemen can stand the heat"

[Subculture]

The main thing you need to be mindful of is the volume of your main WTC in relation to tank volume. Too much pressure building up inside, and you may get leaks on the seals. Also screwjacks with vee threads are only about 10% efficient, so the system becomes inefficient if it's having to compress a lot of air. Try and ensure the WTC volume is at least around five to six times the tank volume

[rwtdiver]

I'm liking it so far Rob...

Thanks Steve!

Still have some engineering and build work to do! Not sure if all this is going to work or not. So far so good!

Rob (Still a crazy old man)
"Firemen can stand the heat"

[SubDude]

I'm liking it so far Rob...

[rwtdiver]

OK! Back to the project at hand! The photos below are of the 1:96 scale Alfa! (As you know I have a 1:96 scale and 1:72 scale Alfa going)





Now before I go any further, you all know this project was going to be totally experimental for me! My plan is to design TWO different type ballast systems for both these boats! The photos are just to show the possible piston system I have in mine for the Alfa 1:96 scale. I finally got the 12V geared motors that I need for the gear system that I am designing for the 200CC syringe unit! Don't know if this is going to work or not, but I will see it through to find out! Lot more design work on the WTC to do!

Rob
"Firemen can stand the heat"

[RCSubGuy]

That is an excellent suggestion. Indeed the techniques and methodology to develop 3D CAD models are distinct from printing. Again it takes time to learn and experiment with different approaches to 3D modelling, particularly when modelling a complex hull shape. So a dedicated sub-forum would be very useful to exchange information.

I agree, to a point. but I don't want to get too granular in the forums. If we extended the same thought to general modeling, we'd have sub-forums for ballast, radios, propulsion, peripherals, hulls, etc, etc, etc. We'd have fifty topics with just a few posts in each. 3D printing is general enough to catch what we need to talk about. If you do a good job of titling the thread, there will be no issues.


Bob