Newby Needs Help on Project

I am totally new to this and would appreciate any help I can get. I have an electronics background but no experience with underwater dc motors or the RC hobby . Which brings me to my current project. I found an old 4" tunnel blower (made for moving air) from my inboard boat and made a mount for my kayak to try and use it as propulsion. It has a ultra cheap 12vdc 1500rpm brush motor and 5 blade fan mounted in a 6" long tube. The set up will run about 2 knots wide open with no waterproofing and a weed guard added to the tube. The blower assembly seems work well for thrusting water and I would like to enhance it with a better motor. The current motor definitely is not something I would regard as reliable or efficient and I would like to mount 2 motors (1 blower assembly on each side) and be able to control them remotely. Which bring me to these questions.

My 5 questions are about RC brushless motors and controls:

1) Do the brushless motors need to be waterproofed for submerged running?
2) What brands of motors are efficient and reliable?
3) What speed controllers are most reliable for RC motors?
4) What RC controller would be best to control 2 motors independently with forward and reverse?
5) Can the RC set up be done easily with a common 12 volt battery?

I am trying to do this on a budget so cost is very important. I hope I am not asking too much.
Thanks in advance
Steve

RenoNuski said:

My 5 questions are about RC brushless motors and controls:

1) Do the brushless motors need to be waterproofed for submerged running?
2) What brands of motors are efficient and reliable?
3) What speed controllers are most reliable for RC motors?
4) What RC controller would be best to control 2 motors independently with forward and reverse?
5) Can the RC set up be done easily with a common 12 volt battery?

I am trying to do this on a budget so cost is very important. I hope I am not asking too much.
Thanks in advance
Steve

Click to expand...

I've never built an e-boat but will try to answer your questions as best as I can.

1. Yes. Hal sensors do not like getting wet. Brushed motors work just fine submerged. I'm not sure how well one would hold up long term, unless specifically designed for submerged operation. I'm not sure how you could go about sealing an RC motor.

2. Lots of people like the larger Turnigy motors from hobby king. I know HK is in the middle or was working to replace their lines of large motors with a new motor. I'm not sure oh the names of those replacements or what's out yet. I just recall mention of a lot of their stock is on back-order because of this.

3. The problem with RC controllers is finding the one that can handle your power needs.

4.12 volts is a bad idea. It will be pretty slow and pull massive amps if you try going faster. 24 volts would be much better.

Thanks Pure!

My goal is not to go faster but just assist in paddling and extending my range and comfort in my kayak without an obtrusive trolling motor.

Really it would probably be better and cheaper to just get a used trolling motor off of Clist or something.

45 bucks http://jacksonville.craigslist.org/boa/2825734252.html

http://endless-sphere.com/forums/viewtopic.php?f=39&t=19313
http://endless-sphere.com/forums/viewtopic.php?f=7&t=13639

I have made a swing up unit that is showing some promise using some hobby king motors and a 12V wheel chair battery. Joy stick controlled and very fishing friendly. It is a god-send on windy days or paddling up stream.
Currently getting ~6 hours on a 16ah battery @ 2-3 knots, ~3 hours @ 5 knots(top speed).
Cost of current configuration <$100
Trolling motor's - Their efficiency, weight, and size are not my answer...been there done that.