Electrics?

[John SeftonParticipant @johnsefton59724]

I really don’t understand electrics. My Mountfleet model Danny Boy has just been launched, but the fuse melted after 5 minutes running. I am using a 6 volt battery. Can anyone give me some tips please. John

[Charles OatesParticipant @charlesoates31738]

Need more details John. What motor, prop,speed control, and fuse rating are you useing.
Fuses usualy blow because you are taking more current ( amps ) than the fuse is rated for, however you can’t just use a larger fuse as it’s there to protect the rest of your gear.
When the fuse blew was the prop fouled with weed etc?
Is the driveline,( propshaft and coupling ) running freely.
Chas

[John SeftonParticipant @johnsefton59724]

Hi Charles, When I bought the kit at the Ellesmere Port Boat Show I spoke to a dealer and asked him for what was necessary for that kit. He supplied a “Johnson” motor but it has no markings on it. Ihave a Hitec SP-6/10A 6-8.4v speed controller. I am using the white metal 4 blade 2.75 in prop that came with the kit (I assume this is not very efficient). I am not sure what the fuse was as it has melted and know nothing about prop speed although I did need full throttle to move the boat at a reasonable speed(not fast).The drive seems ok and there was no weed. Maybe I should replace some of these parts? Appreciate your help, John.

[Charles OatesParticipant @charlesoates31738]

Hi John,frustrating isn’t it, you would expect the gear bought like that to be fine, now to the cure. you have 3 courses open to you. Firstly why not join a club if there is one local to you, lots of people who have been through this sort of thing, and are always ready to help. What area are you in?
Secondly you could try to work this through. The prop is quite large for a direct drive, this puts a large load on the motor, and in response the motor will suck more amps from the battery, that would blow the fuse.
what you need to do is connect an ameater into the circuit to see how much current is being taken, you will need one that goes to 10 – 15 amps. This MUST be conected directly between the battery and the motor, take out the speed control, you do not want to fry that. Test the current drawn while the boat is in the test tank, (bath) so you can see the results under load.As your speed control is rated to a maximum of 10 amps, you will need to change either the motor or prop to arive at a load of not more than 7 amps, leaving 3 amps a a safty margin, because when a motor first starts there will be a surge of current.
Lastly, you could just go to a good model shop, tell them what you have and ask for a suitable motor. Ringing Westbourne models, or model motors direct will produce the same kind of help, both are excellent.
Let me know how you get on.
Charlie.

[John SeftonParticipant @johnsefton59724]

Hi Charlie, Thanks for the most helpful reply, this is the first time I have tried out a forum of any sort and, thanks to you, I am most impressed. I live at New brighton and they have a lake and club so I will go down and chat. I have been a bit reluctant as I feel I am quite an amateur and the people at the lake, with their caps and gold braid, look most professional!!!!
I will let you know how I get on, everything you say makes sense and I feel wiser already. Thanks again, John

[John SeftonParticipant @johnsefton59724]

Hi Charlie, Things have moved on a bit. Before I could fix the electrics someone came up with a good offer for my boat. I explained the situation and they were quite happy so I let it go. I also sold my model of the Joffre and with the proceeds I have bought the Bangarth kit from Mountfleet Models. What would you suggest for this model in the way of motor and electrics? It has a 70mm prop but I will purchase a brass one instead of the white metal. Regards, John

[Charles OatesParticipant @charlesoates31738]

Hi again john, the Bangarth is a great boat, lots of presence on the water. As to what to run it with, everyone you ask could have a different answer and they could all be right, I can only say what I would try.
For swinging a large prop some use a geared or belt drive, it’s kind on the motor and you might get more torque at the prop. A direct drive will be quieter, which is important if you later buy a sound module to mimic the sound of the original engines, these are great as long as it isn’t in a duet with the drive motor, gear whine sorta spoils the effect. If you go for a direct drive get a good low speed high torque motor with a matching speed control. I would use a sun 550 and a condor 20/2 controler. If you are interested in these look at the website http://www.action-electronics.co.uk/ for action products, and VERY importantly give them a ring before ordering and check what I’ve been saying is correct, I’m only human. Action are very highly regarded with great customer service. No I have no conection with them, it’s just what other modelers say.
The model will carry loads of balast so you can put a good size battery in there, but make sure whatever you buy will go through the hatch.
I hope that helps a bit, happy modelling, let us know how you get on.

Charlie.

[John SeftonParticipant @johnsefton59724]

Cheers Charlie, will be in touch, John. Anyone else out there got ideas???

[DickyDParticipant @dickyd]

John probably shouldn’t say this on here but if you also join the
http://www.modelboatmayhem.co.uk forum the owner of Action is a member
and gives Mayhem members a discount.

[Malcolm FraryParticipant @malcolmfrary95515]

Go to a car accessory shop. Buy a blade type fuse mount and a selection of matching fuses, up to the max stated on the ESC and replace the melted blob. THe bayonet type fuse holders tend to get HOT and the plastic does melt. Been there, waited for the boat to drift in…

[John SeftonParticipant @johnsefton59724]

Thanks Malcolm, I have already done that for the model under construction but I’m learning a lot on the forum

[SeasprayParticipant @seaspray]

 Hi

You got to watch some of those johnston motors that don’t have numbers on them. I had a 600 in a Bilge hull and it was drawing 17amps in the bath. I didn’t know that till I tested it, cause it got too warm running on the bench. I was later informed that they use these motors in power tools..no thanks. The electronize ESC got hot but handled it. I now use mark up motors ie Graupner  400,500E,600. or 777, or 555. MFA ranges and the likes. You know what your getting when you buy named motors.

Thats not to say Johnson’s motors are a bad motor. Just I know what I prefer to use.

Good Luck 

[Ethan Hunt 2Participant @ethanhunt2]

hey there all, new here to MB… I wonder if anyone can suggest a good website or shop within middlesex that I can buy a circuit board… 2nd, does anyone know where I can get my hands on plans for large mono-hulls or 3/4 point hydros… cheers.

[SeasprayParticipant @seaspray]

Hi

Update on the motor choice. I have fitted a Graupner Speed 500 Ecko in the Hull. It only draws 2 amps or less on load ( in the bath) doesn’t heat up and gives me enough revs to push her through the water.

 Ethan Hunt 2

Try Ebay lots of choice there and some model shops now are on it. Might even be your local shop on it.

Good luck

[KristophParticipant @kristoph]

Thank you seaspray, I will give that a go…

[Bernard AllenParticipant @bernardallen88612]

Hi,

Just read all the answers to the question put be John and in someways I am in the same situation. Having built a Model Slipway "Puffer" I am now scrastch building a Oil Rig Support Vessel which according to the plan does not indicate any scale. When built (Balsa) it will be about 24" long, 5.5" on the beam. The plan is actually out of my Model Boat Magazine Dec.2005.

Whilst the suggestion and test indicated a size 350 motor!!. what criteria is there to denote what size motor fits what size boat.

Whist I am well into retirement, these are my first r/c boats ever built and not having a clue I joined my local club. You couldn’t wish to meet a more friendly lot and extremely helpfull. Should have done it years ago. Best of luck and Enjoy.

[SeasprayParticipant @seaspray]

Hi Benard

Been with the boats for years and even I have to ask and do trails to find a suitable motor for the model being built. I am now a brand man ie I buy Gruapner motors as through the years I tried non branded motors.Theres more than one brand on the market so there is a great choice and with that comes the headaches. there is not a formula for motors/model.Try the 350 sounds good for a balsa hull use a mfa motor mount or robbe so if you have to change the motors it is 2 screws off 2 on. Your club members will offer their ideas on the motor needed and it really is a trail and error thou you could be lucky 1st time. Have a look at the electronize site http://www.electronize.co.uk they have motor spec/prop/amps  and small motors on their site

Good Luck

[Bernard AllenParticipant @bernardallen88612]

Many thanks Seaspray for a prompt & helpful reply. I will certainly take a look at what electronize has to offer.

[SeasprayParticipant @seaspray]

Hi All

 There is the MFA site too and a dealer called Model Motors Direct I also bought some motors off  Wingertaz on ebay I believe he has a model shop in Blackpool but don’t quote me on that.

From hearsay its best to buy electronize products from a model shop if in stock.

Good Luck

[KristophParticipant @kristoph]

im looking to run 2x SPEED 600 RACE MOTOR 8,4 V (#6312 Graupner), but im at a stuck as to which speed controller(s) i should be using with these, and the best battery(s) for a good ‘run’ time… any help would be much appreciated. Thank you

[SeasprayParticipant @seaspray]

Hi

I would look at running the motors seperately on ESCs. I  beleive the cotrollers can be operated together using a Y lead.But find the voltage draw that your 600 requires to make sure your choice of ESCs are high enough rated for the 600 as it draws a good few amps and with two motors twice as much. You can also use two packs together giving you a longer running time but ask how to connect them up as I am not too sure on this.

I use a 8.4v 2100mah J.Perkins pack bought from Westbourne Models gives me 10-15 minutes as s with the 600 ECKO motor.

Lots of controllers out there  Mtronics, Action,Astec, and ofcoure Electronize. All good controllers.

You might try and see if you can use lead acids (Gell Cells) instead of stick packs. just a thought as the new Graupner Moonraker uses 3 x700 motors on 2x 6v acids wired in series giving 12 volts with the same amps.

Good Luck

[KristophParticipant @kristoph]

hey seaspray, soz for the late reply, thank you very much for the reply… been very useful… I will try and up get some pics done for you as well, I am hoping it will turn out ok… I hav eheard of a place called The Blackpark, in Iver…any ideas??? Ethan

[John SeftonParticipant @johnsefton59724]

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