Brushless?

[jr3d]

I am working on putting together an alpha not sure what size yet. My goal is to have a very fast very nimble sub. I was wondering if a brushless motor running on lithium polymer batteries could be handled by a model submarine.

[bigdave]

Sure! I don't see why

Sure! I don't see why not. I know some guys that have brushless setups in there subs. Low speed is not really as good. The brushless motors do not usually cog as well at low speeds. But low speed sounds like it is not a problem for you. Castle makes some F/R speed controls for brushless motors. BD.

[jr3d]

I am already an advanced

I am already an advanced 3D aerobatics pilot in RC aircraft so brushless motors and esc's. The only thing is, in every video of an RC sub I have seen, the sub looks like it is just CRAWLING along, so say for a 1/48th scale boat, how fast could you get it going without it self-destructing? Maybe I am just thinking that the subs are moving slow when they are pushing the limits of their speed range they can handle. The idea I have in my head is like a racing surface boat, only in sub form.

[bigdave]

Check out my thread on

Check out my thread on my Sushi sub. It is close to the limits that a model sub can attain. It is very hard to control, and scares the crap out of me when I run it. I still have yet to dial it in. The guys in Germany are big on high speed subs. I am just a nuby!! BD.

[jr3d]

Where is the sushi sub

Where is the sushi sub thread I did a search and only found this thread?

[davietait]

Dave has it on the

Dave has it on the Subpirates site

http://www.subpirates.com/viewtopic.php ... hi&start=0

Davie

[jr3d]

all there is on that

all there is on that thread is a pic of a brushless motor

[aeroengineer1]

Inrunner brushless motors do not

Inrunner brushless motors do not have much of a cogging problem, and if you use a gear reduction drive, you diminish that even further. Example, if there are 9 cogs in the motor, and you put it into a 9:1 reduction, you will get 81 cogs per revolution. That is a cog every 4 degrees. that is not too bad.

Adam

[tsenecal]

I now have two submarines

I now have two submarines that are brushless,

a rebuilt SWM blueback that uses an eflite 400 740kv outrunner with a CC mamba ESC connected direct drive. it runs fine. I was concerned about cogging at first but it is a non issue.

the second brushless addition to my sub fleet is a 1:32 type II uboat that uses two of the identical eflite 400 740kv outrunners direct drive with a matched set of CC mamba ESCs. it has been in the water for a total of about 5 minutes run time, and it also has slight cogging at extremely low speeds, but time will tell whether this is an issue or not.

neither of these beasties was designed to be a speed demon like BDs sushi, but the blueback could very easily be.

Tim

[jr3d]

I think I am gonna

I think I am gonna try and put together a 1:400 scale alpha and just leave all the little detailed stuff of it, I am no scale purist. the thing I am thinking is gonna cause me trouble is how I am gonna make a WTC for it.
Your help so far has been great.

[Rogue Sub]

well you can buy one

well you can buy one from big dave or you can be a cheapo like me and make it out of pvc. Lexan is better though.

[jr3d]

Big Dave, do you have

Big Dave, do you have a WTC that will fit the sub I am looking at? If so, I would be happy to buy one.

[aeroengineer1]

Hey, I am not wanting

Hey, I am not wanting to burst your bubble, but there are no esc's that will fit your boat even if you make it a dry hull. You boat at that scale is going to be under 1" in diameter and about 9" long. The only brushless controller that I know of that is forward/reverse is the mamba, and that one is bigger than what you have. If you know of another, please inform me. I would love to take a look at it. also, the area where you are going to be doing your controls, man you are going to have to work with a magnifying glass and tweezers.

If you are looking for small but workable, you might check out the U212 offered by revell, or the skipjack class that has been done by a few different companies at 1:232 scale. I think that you might get the mamba into that one. The trumpeter Kilo might also be a great option.

Adam

[Rogue Sub]

Whoa! yeah i didnt even

Whoa! yeah i didnt even look at the scale. Working something that small and brusheless would be something amazing to see though!

[jr3d]

I could just use an

I could just use an ESC without reverse couldn't I? and i am used to working with small model aircraft so this will still be a challenge none the less.