Model Boat Mayhem - Forum

Please login or register.

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

Author Topic: Brushless ARUN Lifeboat with pics  (Read 9626 times)

lifeboat paul

  • Guest
Brushless ARUN Lifeboat with pics
« on: March 25, 2008, 10:38:06 PM »

Hi, I  was Impressed with the  Severn lifeboats of Phil Lock and his fellow model lifeboaters at Warrick last year , so I decided to build one from a semi kit , I chose the Arun lifeboat which is now manufactured by models by design, the hull and deck are pre-jointed and are of the highest quality, I am totally impressed with the fibreglassing.

It`s a large impressive boat so I wanted it to have a speed to impress as well. So I have fitted two of the largest brushless motors I could find and a pair or brushless speed controllers -they now are available with reverse.
I also have installed a graupner digital sound unit that runs though a amplified equalizer in to a six inch quality speaker, ( theres more hifi in this boat than in my house!!)

I have been able to make the windscreen wipers work in a linear direction(s) via a cannibalised servo.
The Y-boat will be lifted of the deck and swung overboard and the lowered by utilising two servos.
the radar, lights and flashing strobe beacon can all be operated by a single servo and set of micro switches progressively
I have had a test run on the water and it is mega fast, so fast one of the rudders seemed to vibrate and de-laminate it`s self (see pic)
Paul
Logged

Proteus

  • Guest
Re: Brussless ARUN Lifeboat with pics
« Reply #1 on: March 26, 2008, 12:46:26 AM »

any chance of some dimenthions and how it goes and what motors and speedo's are you using, it looks very nice and light , I do like the wiper idea. keep up the good work,

fredy
Logged

lifeboat paul

  • Guest
Re: Brussless ARUN Lifeboat with pics
« Reply #2 on: March 26, 2008, 10:12:50 PM »

Hi fredy,
The boat is 52 " long , I have 75 mm props fitted, the two speed controllers are ones that I bought from eBay , the seller is called revolution shop, they cost 26.00 from china inc p+p , here is the spec from there eBay listing -Turborix Advance 50A Bi-directional Brushless Motor Speed Controller
(with forward and reverse motion control function)
Model Number : PESC0009
Specification: Current (A) : 50A
BEC : 3A
Neutral : FORWARD/BACKWARD RATIO SETTING: 70/30, 60/40, 50/50(default), 40/60, 30/70 
Size : 62.30mm x 29.15mm x 15.39mm
Suitable Battery :  LiPo (3-6 cells);NIHM (8-18 cells)
 Weight : 45g
 The motors are also from Ebay ( 26.00 inc p+p)-Brushless outrunner motor Emax BL4030 from the seller -hkp2ps2, they measure 40x30 mm and have a 6mm shaft.
Even though the spec for the speed controllers does not mention using lead acid batteries they work fine on it . I am using two 12v batteries in series delivering 24vollts to the controllers -1 volt over there limit so I have fitted a cooling an as they get hot and cut out on full power due to overheating.
How does it go then- IT IS EXTREAMLY FAST ,lifting right out of the water -very impresive !!!. 

Paul
Logged

Proteus

  • Guest
Re: Brussless ARUN Lifeboat with pics
« Reply #3 on: March 26, 2008, 10:54:49 PM »

Thats very impressive , what sort of run time do you get and what amp hour batteries are they ?  have you used brushless on any other project before, it is very difficult to find people who have used these motors in scale boats with success did you have any teathing problems at all I have a 34" peckassa with twin screws that I would like to use brushless in thanks

Fredy
Logged

lifeboat paul

  • Guest
Re: Brussless ARUN Lifeboat with pics
« Reply #4 on: March 27, 2008, 11:13:29 PM »

Hi, The two batteries I am using in series are two 12v 7ah lead acids, I don't know the run time yet as every time I have put the boat on the water something has gone wrong-always to do with the propulsion-threads stripping on the universal couplings, rudders breaking off, esc overheating, the universal couplings themselves breaking apart- all to do with the size and weight of the boat and the amount of power i`m trying to put through the shafts.

The only draw back with the brushless set up is the programmable esc`s need to be set every time you switch on, That means that you have to turn on and move the throttle stick to the full throttle position the back to neutral and then to full reverse to set the limits , then all is as per usual.


I now have changed the sound unit for the model before I was using the Graupner top sound 1 digital module, which is a great sound unit with additional sounds built in all accessable from one extra channel, but I was never happy with the sound as this unit was meant for trucks which is one of the reasons why I fitted the graphic equaliser to try and change the sound.

I have now fitted the jjc sound unit ( bought it on eBay the other day for fifty quid) I have fitted a small fan to the unit to keep it cool ( see pic) as I am concerned about it going wrong- and theres no more JJC to repair it anymore. Again I am running it through the amplified equaliser and boy is it loud- you should see that six inch speaker cone move!!
Logged

Proteus

  • Guest
Re: Brussless ARUN Lifeboat with pics
« Reply #5 on: March 27, 2008, 11:53:24 PM »

Thanks for that info i look forward to any pictures of it sailing or any furthere updates.

fredy
Logged

andywright

  • Full Mayhemer
  • *****
  • Offline Offline
  • Posts: 538
  • Location: Barry, South Wales
    • Windpowersails
Re: Brushless ARUN Lifeboat with pics
« Reply #6 on: March 29, 2008, 06:14:34 PM »

And me, I'd love to see pictures of it going, when you have the small problems sorted.
Logged
Navigational Aids vessel Master. Old Conway 70-72

2772e

  • Simon
  • Full Mayhemer
  • *****
  • Offline Offline
  • Posts: 452
  • The Sea Shall Not Have Them
  • Location: Colchester, Essex
Re: Brushless ARUN Lifeboat with pics
« Reply #7 on: March 29, 2008, 07:18:56 PM »

Hi Paul,

I am really interested in how much run time you get. I am running a large RTTL with lead acid and a couple of big mototors and only get about five minutes run time.

Thats on 18 volt 12 amp?

BW

Simon
Logged
Rubbin is Racin!

lifeboat paul

  • Guest
Re: Brushless ARUN Lifeboat with pics
« Reply #8 on: March 31, 2008, 11:19:24 PM »

Had a good day at the boat pond this Sunday, the boat performed well with no breakdowns for once. I can now give some indication of the run times. I got about half an hour out of the 2x 12v 7ah batteries (24v) this was some runs at full throttle and the rest at more scale like speeds.
I would guess that if  I kept it a full throttle it would last only ten minutes ( if the speed controllers could take it) , however the motors do not get hot.
I had to take the picture of it at full throttle myself whilst trying to control it ( everyone else said they could not see the screen on the camera due to the sun) , so it is a bit distant. It does not look that fast in the picture but it was really moving and creating hell of a wash, enough to upset my fellow club mates ( one puffer on the other side of the pond was brought in quick as it was decks awash).
 I have not been able to attach the pics of the boat at full throttle as the files are to big - can anyone tell me how I can reduce the file size ?
Paul

Logged

2772e

  • Simon
  • Full Mayhemer
  • *****
  • Offline Offline
  • Posts: 452
  • The Sea Shall Not Have Them
  • Location: Colchester, Essex
Re: Brushless ARUN Lifeboat with pics
« Reply #9 on: April 01, 2008, 07:44:22 AM »

Paul,

There is a resizer tool/software on the main forum page (menu on the left). Download it and run it dependant on operating system you are using.

Load the picture onto your pc, right mouse click and then resize, i usually go medium.

BW

Simon
Logged
Rubbin is Racin!

lifeboat paul

  • Guest
Re: Brushless ARUN Lifeboat with pics
« Reply #10 on: April 02, 2008, 11:29:09 PM »

 O0
Thanks Simon for that, I have now resized the pics .
Paul.
Logged

lifeboat paul

  • Guest
Re: Brushless ARUN Lifeboat with pics
« Reply #11 on: May 08, 2008, 11:12:10 PM »

I took the Arun to Beale park on Saturday, It performed well, but after 15 minutes or so it stopped dead in the water , at first I thought the battery connector had come off( spade connector) but  once it had drifted in , on inspection I found that the  plastic insulator within the main switch had melted with the heat build up , the switch is a old fashioned heavy duty toggle switch rated at 10a @ 250v .
I was running on 24v so using a bit of simple maths it should be rated at 100a at 24 v ? sounds a lot anyway I am now going to fit a relay . I have attached a picture take of the Arun whilst on a high speed turn,the photo was  kindly taken be Kim from from the model lifeboats association.
Paul.
Logged

BJH

  • Guest
Re: Brushless ARUN Lifeboat with pics
« Reply #12 on: May 09, 2008, 08:44:59 AM »

Hi,

I think you will find that the 10A rating was at 250V a.c.

Switches are often specified at 250V a.c. and then another current figure at a lower d.c. voltage.  I don't think that you can assume that at 24V  you can switch 100A  with a 10A 250V a.c. switch. It will usually be around the same or even a lower current at the sort of voltages that are used by model boats (6, 12, 24V d.c. say).

I think the key is to carefully study the specification sheet for the switches you intend to use. You can usually find these if you have the part number and manufacturer of the switch (and these are usually marked on the switch) using Google and the internet.

BJH
Logged

Shipmate60

  • Global Moderator
  • Full Mayhemer
  • *****
  • Offline Offline
  • Posts: 5,263
  • You bark - I will bite!!!
  • Location: Fareham
Re: Brushless ARUN Lifeboat with pics
« Reply #13 on: May 09, 2008, 09:20:44 AM »

Heavy Duty Vehicle switches and relays are a useful source.
They are designed to operate as 24 or 48 volts so you get a true current rating.

Bob
Logged
Officially a GOG.

J.beazley

  • Full Mayhemer
  • *****
  • Offline Offline
  • Posts: 877
  • The building never ends
  • Location: Locks Heath, Hampshire
Re: Brushless ARUN Lifeboat with pics
« Reply #14 on: May 09, 2008, 10:46:23 AM »

Ahhhh so Paul you own the fast Arun that i kept looking at most of saturday at Beale then.
I did wonder why it suddenly stopped in the middle of the lake, now we know.

Still its like a scalded cat when it takes off very impressive O0

Jay
Logged
If it floats I'll  build it, if it sinks its a sub either way its in the water so I'm content.

nick_75au

  • Guest
Re: Brushless ARUN Lifeboat with pics
« Reply #15 on: August 24, 2008, 12:41:39 PM »

Im very Impressed with your Arun Paul,
I have a 1:12 56' motor yacht that is looking for a power plant like this, currently I'm going to trial  a twin Darke Horse setup with planetary's and belt drive for a 6:1 reduction. Two motors each shaft. 75 mm 4 blade propellers. I'm aiming for a maximum of 40 amps per shaft or 1.2 horsepower per shaft.

Do you know the amp draw flat stick of the boat.

The problem with the 240 volt 10 amp switch is contact resistance. An example is say the resistance of the contacts is 0.1 ohm (guess) at 240 volts the switch is "consuming" 0.01amp  or generating about 2.4 watts of heat. The same switch at 24 volts is "consuming" 2.4 amps or 57 odd watts of heat (Think same wattage of light bulbs and the heat they produce) which the poor old switch has no way of dissipating. Thats why you see low voltage contacts and switches rated for high current with lots of beef.
Regards
Nick



Logged

DaveB

  • Guest
Re: Brushless ARUN Lifeboat with pics
« Reply #16 on: October 29, 2008, 07:45:54 AM »

Hi Paul
I saw on one of your posts that the couplings strip, i had an odd motor shaft size in one boat and decided to try couplings for ic boats from SHG they have a large rubber centre section which takes up a large amount of torque on startup it may be worth giving them a go not that expensive either.
Dve
Logged

Garabaldy

  • Guest
Re: Brushless ARUN Lifeboat with pics
« Reply #17 on: October 29, 2008, 08:18:40 AM »

What about trying out one of MMM safety couplings?  These too have the rubber centre section which you can cut to the length require to suit whatever boat its going in.  Cheap too!
Logged

Martin [Admin]

  • Administrator
  • Full Mayhemer
  • *****
  • Offline Offline
  • Posts: 19,048
  • Location: Peterborough, UK
    • Model Boat Mayhem
Logged
"This is my firm opinion, but what do I know?!"    -   Mayhem FaceBook Group!

grasshopper

  • Full Mayhemer
  • *****
  • Offline Offline
  • Posts: 740
  • Location: Lincolnshire!
    • A1 Hobbies Ltd.
Re: Brushless ARUN Lifeboat with pics
« Reply #19 on: October 29, 2008, 11:59:53 AM »

Tremendous looking boat.

I read that you've added an equalizer to the audio system to modify the sound - can I just say that if you mounted the speaker in / over a sealed enclosure or box you would increase your bass reponse. Mounting the speaker as you've done in the hull doesn't allow it to compress air to make the sound efficiently.
Logged

malcolmfrary

  • Full Mayhemer
  • *****
  • Offline Offline
  • Posts: 5,564
  • Location: Blackpool, Lancs, UK
Re: Brushless ARUN Lifeboat with pics
« Reply #20 on: November 02, 2008, 11:47:53 AM »

There are several ratings to consider with switches - the current that they can live through switching, and the maximum that they can carry without melting.  Another consideration is the voltage that they can stand up to when releasing.  A releasing switch will momentarily create an arc.  The contacts have to separate far enough for the arc to give up before damage occurs - a high voltage might result in the arc continuing when the contacts are as far apart as they can get.
Provided that the voltage is within limits, the current that can be carried or switched is the same whether it is running on 240, 24 or 2.4 volts.  Sticking 10A through a 10A switch is the limit, whatever the voltage.
This is one of the aspects that gives electric its "Black Art" heading.
Logged
"With the right tool, you can break anything" - Garfield

morgsy

  • Shipmate
  • *
  • Offline Offline
  • Posts: 6
  • Location: Aberdare
Re: Brushless ARUN Lifeboat with pics
« Reply #21 on: May 31, 2011, 09:27:28 PM »

Did you make your own stanchions or are they bought?
If bought where from?

Kind Regards,
Chris
Logged

mog10

  • Guest
Re: Brushless ARUN Lifeboat with pics
« Reply #22 on: June 05, 2011, 04:07:51 PM »

looks good im thinking of fitting those motors to my 1:12 severn , ill keep you posted on how it turns out

Chris
Logged
Pages: [1]   Go Up