Model Boat Mayhem - Forum

Please login or register.

Login with username, password and session length.
Pages: [1]   Go Down

Author Topic: Tug Motor and ESC help please  (Read 5367 times)

Firebod-7

  • Guest
Tug Motor and ESC help please
« on: November 24, 2009, 09:37:15 PM »

   Hi, can anybody help me with the motor and ESC choice for the Joffre tug boat kit by Caldercraft. I understand the workings and wiring of the motor and ESC, so that's not a problem.
 
  I would like the ESC to have a BEC fitted to eliminate a separate battery for the receiver. Are the ESC's usually made with off being centre stick, up forward, down reverse? I have been told that I should change the included white metal prop for a brass one, also what are your thoughts on the voltage, 6v or 12v.

Thanks for your time best regards Richard.
Logged

Shipmate60

  • Global Moderator
  • Full Mayhemer
  • *****
  • Offline Offline
  • Posts: 5,264
  • You bark - I will bite!!!
  • Location: Fareham
Re: Tug Motor and ESC help please
« Reply #1 on: November 24, 2009, 09:55:43 PM »

Richard,
The first consideration is the prop and work back from that.
The most popular ESC with bec is the MTronics Viper. A 15 amp will be sufficient but do FUSE the supply wiring at 10 amps.
For a scale brass prop 6 volts will be sufficient and any motor that will develop up to 5000 rpm on 6 volts.

Bob
Logged
Officially a GOG.

tolnedra

  • Full Mayhemer
  • *****
  • Offline Offline
  • Posts: 259
  • Location: North Dorset
Re: Tug Motor and ESC help please
« Reply #2 on: November 24, 2009, 10:23:34 PM »

Hi again Richard,

My 'Joffre' runs on 6v, 7ah sealed lead acid battery. I have fitted a brass prop, and use an Mtronics 15amp ESC. (originally a Bob's board!!! almost antique now!) My motor is a 6v Decaperm, somewhat expensive these days, but as it has been in the boat since I built it 25 years ago, it has proved its worth beyond any doubt! With this setup I have run in our club's mini-marathon of an hour's continuous running at full speed, having been pottering about all the morning on the same battery previous to the afternoon's marathon. At the end the motor was just slightly warm, and the battery still had plenty of life left in it. Hope this has been of help.

Danny

PS With regard to the question ref stick position on the Tx, you have to set the Mtronics ESC up the first time, detailed instructions are included, and yes, if your wiring is the right way round, centre position is off, full up on the stick is full ahead, fully back on the stick is full astern.
Logged

Bradley

  • Guest
Re: Tug Motor and ESC help please
« Reply #3 on: November 24, 2009, 10:31:55 PM »

As far as props are concerned, have a look at this website -

http://www.gsitek-props.co.uk/

I can certainly recommend him.  His website covers all his prop sizes, shafts, etc., etc. and ordering is easy. 
No connection except as a very satisfied customer. :-))

Derek.
Logged

knoby

  • Guest
Re: Tug Motor and ESC help please
« Reply #4 on: November 24, 2009, 10:48:00 PM »

Hi Richard, definatley agree you should ditch the white metal prop & go for a brass 1. once you have chosen your prop, contact action electronics ( he is a member here full leather jacket) his products are top quality & his advice is second to none. I one of his many satisfied customers here

Cheers Glenn
Logged

Firebod-7

  • Guest
Re: Tug Motor and ESC help please
« Reply #5 on: November 25, 2009, 05:33:54 PM »

Hi thanks for all your advice, I think you have covered everything between you all and Danny I think it was yourself who first told me to change the prop. Really kind of you all, thank you again :-))
Logged

787Eng

  • Guest
Re: Tug Motor and ESC help please
« Reply #6 on: November 25, 2009, 06:08:23 PM »

My 'Joffre'also like "Tolnedra" also runs on the following:
6v, 7ah sealed lead acid battery.
A 6v Decaperm motor.
Prop shop 4 blade brass prop.
Electronize 15amp speed controller.

The only thing I find is the decaperm gearbox is a little on the loud side for my taste. Something I have been contemplating is fitting a MMM T12 in its place, more than enough torque and will be very quiet. Very nice motors have 2 fitted into my Imara and 2 in my Lady Wooes.

Pictured is my Imara doing a little towing %%
 
Mark
Logged

Firebod-7

  • Guest
Re: Tug Motor and ESC help please
« Reply #7 on: November 27, 2009, 09:19:00 PM »

Nice picture Mark, I love it :-))

 Thanks for the advice. One question, do you use the gearbox to take the motor speed down? Bob let me know that I was looking for 5000 rpm max. Would I benefit from a four blade prop. I have ordered a 38mm 3 blade brass prop, the same size as the one included. Now having fitted the rudder and drive tube in place I can see with the white metal prop in place I could have ordered a bigger prop. Would that be wise? Thanks for all the help all the best Richard
Logged

787Eng

  • Guest
Re: Tug Motor and ESC help please
« Reply #8 on: November 27, 2009, 10:07:34 PM »

Richard,
On the Decaperm motor yes I use the gearbox.
Not really sure of the performance differences of a 3 v 4 blade props. Just have a word with Prop Shop and tell them what your setup is and they will supply the right prop. Cannot remember the size but its a lot larger then the white metal one (it measures from blade tip to blade tip 51mm). As I said before its a 4 Blade.

Mark

Logged

Shipmate60

  • Global Moderator
  • Full Mayhemer
  • *****
  • Offline Offline
  • Posts: 5,264
  • You bark - I will bite!!!
  • Location: Fareham
Re: Tug Motor and ESC help please
« Reply #9 on: November 28, 2009, 09:22:11 PM »

Firebod-7,
The Deccaperm motors 6 or 12 Volts run at 2750 rpm but ae they are geared dont lose revs unless very heavily loaded.
1 problem with these motors is the noise of the gearbox.
Unfortunately steam tugs are almost silent.
Deccaperms were used in large warships as the noise simulated a gas turbine.
Direct drive should be almost silent.
The trick is to balance the motor to the motor.
A plastic prop will need the 5000 rpm but a brass prop will run hapily on 3000 rpm.

Bob
Logged
Officially a GOG.

Firebod-7

  • Guest
Re: Tug Motor and ESC help please
« Reply #10 on: November 29, 2009, 06:47:00 PM »

Hi Bob, I have ordered a 50mm brass prop, I have had delivered a 38mm brass one but it looks lost in the space in front of the rudder. What motor will give me the sort of scale prop rpm for the Joffre?
   Rudder stern tube and rudder servo are now in place. The plan said to run the stern tube through as near level to the keel as possible, this gives me 30mm to center of drive from the bottom of the hull. If I fit a motor like MMM T12 the motor drive shaft will end up higher and out of alignment. Would it be OK to tilt the motor downward and use a universal coupling?
   Do I need to fill the stern tube with grease. Sorry for all the questions but this is my first meaningfull build and I would like to get it right. Thanks for you time regards Richard
Logged

Shipmate60

  • Global Moderator
  • Full Mayhemer
  • *****
  • Offline Offline
  • Posts: 5,264
  • You bark - I will bite!!!
  • Location: Fareham
Re: Tug Motor and ESC help please
« Reply #11 on: November 29, 2009, 07:34:12 PM »

Firebod-7,
The Joffre is only 775 isn mm long, with a scale looking prop you will only ned the lower end of the rev range, about 3000.
MMB (Marks Model Bits) did a superb mabuchi 550 motor which would have dropped straight in with no complications.
For such a large prop you may have to accept a free running speed well in excess of scale.
Model Slipway do supply geared motors and MMB have another 2 which are suitable.
MMB: http://marksmodelbits.ieasysite.com/index.html

Bob
Logged
Officially a GOG.

DickyD

  • Full Mayhemer
  • *****
  • Offline Offline
  • Posts: 9,497
  • www.srcmbc.org.uk
  • Location: Southampton UK
    • SRCMBC
Re: Tug Motor and ESC help please
« Reply #12 on: November 29, 2009, 08:06:48 PM »

Hi Firebod-7

My Al Khubar tug runs on 2 Model Slipway MFA 500  geared 2.5:1 (6v) with 50mm props.

These have the shaft at the bottom of the gear box which might help you. You dont really want to run out of line

Prop shaft grease is a good idea as it stops water getting in, not to much though. Do not use ordinary grease you want silicone.

 
Logged
Richard Solent Radio Controlled Model Boat Club http://www.srcmbc.org.uk

Firebod-7

  • Guest
Re: Tug Motor and ESC help please
« Reply #13 on: November 29, 2009, 09:53:59 PM »

Bob and Richard, thanks for your information and the links. I will stick to the scale size prop I already have, I do want it to look right as well as handle well. Thanks again, your help is very welcome and appreciated, best regards Richard. :-))
Logged

787Eng

  • Guest
Re: Tug Motor and ESC help please
« Reply #14 on: November 30, 2009, 08:00:52 PM »

Richard,
Just measured the Dia of a T12 and its 52mm, so with 30mm you should have enough clearance from the bottom of the hull as 52/2 = 26mm. Its going to be tight but its one great motor.....

MMM also make an alignment tool to make sure the propshaft is aligned in all directions with the motor.

Mark
Logged
Pages: [1]   Go Up