Engel Akula K-317 Panther

[trout]

I received this several months ago from Scott. He was the second owner and this unit needed to be finished up.
In a water test there was some areas that were causing leaks. One are is the installed bow thruster. It was removed and the openings were fiberglassed over.

Taking out the bow thruster was definitely a quick dive into the workings of this sub, which is a good thing actually. You learn how it works and what goes were.
One of the issues this thing had was the bow planes not fully deploying. I cannot tell you how long it took to figure it out, but it was a lot of time. Things just would not work right. In fact, it seemed it got worse and worse every time I tried to get the unit to remember the range of the servo. Then by luck, I found the magic order to get it working.
Now, I am in the process of gluing in velcro to attach some parts.
Here is were I am at:

The batteries are stacked to keep the velcro flat.

[He Who Shall Not Be Named]

What a screaming nightmare!

David

[RCSubGuy]

Those Engel kits are wonderful... if and when they work. Seems there is always something needing adjustment, tweaking, repairing or maintaining. Having all the bells and whistles is great, but I vastly prefer a simple sub that goes forward and back, up and down.

[He Who Shall Not Be Named]

Yeah, agreed. tinker-mongers like us love to get arm-pit deep into such gadgets. But how many of these expensive kits wind up sitting in the garage loft, half-started, only to be taken to the city dump once the old-fart -- not even knowing how to hook up a servo to a receiver -- drops dead.

David

[trout]

What a screaming nightmare!

David

You can say that again (but don't)!

My goal in this hobby is to learn all I can. This sub is a multi learning experience. From working with fiberglass, twin piston ballast, to even the mast raising and lowering, it is additional knowledge that I have gained. It is an incredible engineering feat and can't wait to get it trimmed and running.
Bob, you are right, this is not the easiest sub and the Sub-Drivers work so well with far less techno in it. Once I have this working, I cannot wait to hand it over to Sam - he does not know it yet.
By the time I get done with this, I hope to have the wiring in a much neater state. It was pretty tidy when I got it, but disemboweling the sub to get to the bow thrusters made me have to undo so much of the wiring, then top that with working on the bow retract and I pretty much disassembled the entire sub.

As a side note, it reminds me of working on my first Sub-Driver. I had to take that apart and as "scary" as that was to a newbie, it really allowed me to confidently understand how it worked and dispel the false fears associated with it.

[trout]

I noticed the end of the bellows is getting bad. the rest cannot be far behind.
Any ideas for another set of bellows? What size would I order?
Peace,
Tom

[HardRock]

Send me your address again. I have some spare ones here.

[Subculture]

Engel submarines aren't any more sophisticated than other boats with ballast systems. it's solely because a lot of mechanisms that are normally concealed in black boxes e.g. servos and the like, are open and exposed.

I prefer their later kits with bayonet ringed cylindrical enclosures. I think some aspects are rather heavily engineered e.g. their periscope mechanisms are particularly heavy duty and the motors on their tanks tend to be larger than really necessary IMO.

However they do last.

As an alternative do look at Ron Perrotts wtc with twin piston tanks, which offer the same level of performance at a much lower price, and with the advantage you can move the cylinder from boat to boat.

[trout]

Crimeny! This boat is going to be the death of me!
Got the bellows replaced, leaks patched, and verified all systems are a go. Placed the sub in the water test facility and still some bubbles from the main hatch seal and one nut at aft end, no biggie. Tested the bow planes, worked flawlessly, and tested masts.....masts would not rise, brought my ear close....I could hear the motor running, manually pulled the stop switch, that worked both directions. What in the world? I put a bundle of weight at the bow since it will not submerge even with tanks filled.
Put the sub back on the table and opened it up....The aft piston must have shifted because it's screw pushed and bent the motor housing pushing the gear away from the larger gear. So, I have a question....does a brushless motor need to have an ESC or can having power only and limit switches work?

[He Who Shall Not Be Named]

Crimeny! This boat is going to be the death of me!
Got the bellows replaced, leaks patched, and verified all systems are a go. Placed the sub in the water test facility and still some bubbles from the main hatch seal and one nut at aft end, no biggie. Tested the bow planes, worked flawlessly, and tested masts.....masts would not rise, brought my ear close....I could hear the motor running, manually pulled the stop switch, that worked both directions. What in the world? I put a bundle of weight at the bow since it will not submerge even with tanks filled.
Put the sub back on the table and opened it up....The aft piston must have shifted because it's screw pushed and bent the motor housing pushing the gear away from the larger gear. So, I have a question....does a brushless motor need to have an ESC or can having power only and limit switches work?

A brushless motor does not have the mechanical switches to shift/turn on-off the field to maintain the force with the stator that gets the thing going and maintains torque. Get rid of the commutator (brushless ... duh!) and you've created the need to place an input circuit that both senses rotor position and then pulses the current to be in phase with the optimum positions of rotor-to-stator fields.

Yeah ... you need a brushless type ESC, Tom.

Ain't brushless wonderful!



David

[greenman407]

Tom, a brushless motor is driven by AC power. The ESC takes DC and rectifies it into AC and then regulates how much the motor receives based on your commands. So you cannot do without the ESC.

[greenman407]

Oh........sorry Dave, I did not see your post answering Toms question.

[trout]

Had I not been so frustrated, I should have recalled that and not ask a dumb question. Sam saw how frustrated I was and he reminded me something I tell him when working on a project "It is just fluff, dad, get it functioning first, then worry about it." When did he get so smart? He is right, it is the same advice given to a new person getting into the hobby. Thanks guys for the response. When I get to that timeframe, I will ask more of what to use.

[He Who Shall Not Be Named]

Had I not been so frustrated, I should have recalled that and not ask a dumb question. Sam saw how frustrated I was and he reminded me something I tell him when working on a project "It is just fluff, dad, get it functioning first, then worry about it." When did he get so smart? He is right, it is the same advice given to a new person getting into the hobby. Thanks guys for the response. When I get to that timeframe, I will ask more of what to use.

Your kid made a sound observation -- likely something he heard mumbled by his old-man.

Unlike touchie-feelie people who insist that there are no stupid questions (and that everyone is equal, man is capable of destroying this planet, and selflessness is a sound philosophy, yadi-yadi-yada), I maintain that there ARE stupid questions. I see them all the time. And .... sometimes .... those stupid questions are raised by me (gasp!). Good dope needs repeating from time to time. Repetition is the grease of retained knowledge.

Plow ahead and carefully pick and chose your sources of inspiration and knowledge. Let source credentials be your guide. Not the personality of the source. Too much feel-good out there. Not enough get-it-done.

People don't come here to get smoke blown up their butt-hole -- they come here for practical knowledge. They come here to get it done. The good stuff needs reiteration. The bad stuff must be damned.

(secure from rant).

David

[HardRock]

Ah Tom. I feel that it is now time to tell you about the four, famous Chinese curses;

1. May you live in interesting times;
2. May you have ALL that you desire;
3. May you be recognized by people in high places; and worst of all
4. May you enjoy the Akula that Scott gave you!