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        Discussion Building 50'' Orkney Express from Robbe

#1 rakec Jan 09, 2013 02:34 AM

Building 50'' Orkney Express from Robbe
 
Hello guys. i am building a 50'' Orkney express from robbe. i received a kit from my old friend, who had it on the basement. it is a lot of plastic and i am building it up. but, i stuck with one thing. i don't know what motor should i use. well, 2 motors. i am thinkig of using motorcycle 12V battery, so motor should be 12V. and what is with esc?or bec, because i need to go forward and backward.
I already build a weedwacker 52'' boat from scratch, so i have some experience with gas motors, but very little with electric, so please, help me out a little bit. boat should go fast, not realy fast, and i want to have some torque.

regards

http://www.smc-noris.de/orkney.htm

#2 Tollytime Jan 09, 2013 02:40 PM

1 Attachment(s)
If your going brushed, I would suggest a pair 700 brushed motors with a 35mm to 40mm prop. Your could use a pair of 550's like in the ProBoat Pt-109, but they may not be enough.

I would think a pair of Traxxas Titan 775's or Mabuchi 775's You will need two Traxxas 16.8v ESC's. There are other brands. The older 14.8v Traxxas may work just the same, but you can go Lipo with the 16.8v

Get some Lipo batteries and a charger. Stop screwing around with lead acid batteries. Do you cary around a motorcycle battery for you laptop? What the heck is it with the motorcycle batteries? I have one to start my snowmobile, and it's a pain in the butt! Takes eight hours to charge the darn thing!!

11.1v 3s Lipo battery would be a good choice for brushed 700's.

Two Astro Flight 25 motors would work, but those are $390.00 each. Nice motors, but a little out of reach for most.

Graupner has the 700BB, but the price is just stupid for something that is out-of-date and almost obsolete.

http://kershawdesigns.com/index.htm

I would use two M4 shafts with four blade 40mm plastic props. I would hook up two Turnigy 3974 2200kv motors with a 160 amp esc for each one. Program them for counter rotation and use a "Y harnes" to control them through the receiver.

I would use two 10000 mAh 7.4v 2s 40-80c batteries for each motor. You could go 11.1v 3s if you want.

This is just in theory, but it should move!!! It should rock!

#3 rakec Jan 24, 2013 03:12 AM

Thanks for some info, but i decided after a lot of forum search and comapre to my budget, that i will use 2x brushed mabuchi RS 555PH-3255 12V DC motors.
now, my question is, what esc? in parameters for that motor i can't find what is A draw, so i have no idea which esc should i use. in some search, i find, that 20A esc should be fine. i want to have esc with bacwards function too, so my question is, will that be fine or not:

http://www.ebay.co.uk/itm/320A-Speed...item4606b5525b

motor specs:

Manufacturer: Mabuchi

Model Number: RS-555PH-3225

Speed@rated Torque: 3950 RPM

Voltage: 9 to 30 VDC

Nominal Voltage: 12VDC constant

Motor Size: 1-7/16" dia x 2-5/8" long.

Shaft Size: 1/4 flatted shaft 1/8 Diameter 1/2" long.

Motor Connection: 3/16" push on terminals

No load speed: 5500RPM

Torque@Rated Speed: 380.3 gm-cm

Stall Torque: 1360 gm-cm

Features: "wrap around" magnetic shield

3mm mounting holes on the face

#4 rakec Jan 24, 2013 02:05 PM

And there are some pics from building. i am current stuck with color choice.

https://lh5.googleusercontent.com/-r...111_183108.jpg

https://lh3.googleusercontent.com/-p...111_183115.jpg

https://lh3.googleusercontent.com/-_...111_183129.jpg

https://lh6.googleusercontent.com/-H...117_153919.jpg

https://lh5.googleusercontent.com/-w...117_182214.jpg

https://lh3.googleusercontent.com/-V...117_182228.jpg

https://lh6.googleusercontent.com/-p...123_171216.jpg

https://lh5.googleusercontent.com/-B...123_181645.jpg

#5 MILLERTIME Jan 25, 2013 12:28 AM

Nice looking boat.

#6 oldtribefan Jan 25, 2013 09:57 AM

Nice progress on your build!

#7 6789boat Jan 26, 2013 01:21 PM

Great job, are you putting a bow thruster in it since it is so long.

#8 rakec Jan 26, 2013 03:20 PM

no bow thruster. it is not in the kit. i think that should be fine without it, but just in case, there is pleny of room to install it.

#9 rakec Feb 06, 2013 02:16 AM

hello guys. some pics, building is doing fine, those water canon take me almost a week. i also have one request. i receive a esc from heli, and everything is in german. i hope someony know something about this esc and can tell me, if i can use him and why are so many wires on it, on the oposite from motor and battery gauge, mcr42-45ho

https://lh3.googleusercontent.com/-2...205_111049.jpg

https://lh6.googleusercontent.com/-m...205_111043.jpg

https://lh5.googleusercontent.com/-p...205_111054.jpg

https://lh4.googleusercontent.com/-Z...205_111100.jpg

https://lh3.googleusercontent.com/-e...205_111105.jpg

https://lh3.googleusercontent.com/-u...205_223606.jpg

https://lh4.googleusercontent.com/-A...205_223616.jpg

#10 rakec Mar 23, 2013 04:28 PM

guys, i am stuck with a problem. i try to run my boat on the water, 2 motors on one esc, and the motors are vibrating as hell. i try to change the aligment and the aligment is perfect. vibration is very noisy. how can i silence that down?

#11 rakec Mar 24, 2013 01:32 PM

Some pics, i installed almost all accessories to the boat, still some work must be done. i need to change the main engines, and i am still waiting to receive the esc which i bought almost a month ago. i will use multi-switch from HK, i already burned one so i need to ordered new one. i will additional installed bigger crane to the left side, because i also have little boat called mowe, which i will have on my boat. crane which is already on the boat, will only be operated manualy, because i don't have enough channels to operate both:confused:

some pics:

https://lh3.googleusercontent.com/-G...324_190141.jpg

https://lh5.googleusercontent.com/-6...324_190133.jpg
rubber around the boat is missing and the wood on the deck is drying at the moment

https://lh3.googleusercontent.com/-b...324_190155.jpg
paint need to be feixed on some places

https://lh6.googleusercontent.com/-m...324_190126.jpg

https://lh4.googleusercontent.com/-e...324_190119.jpg

https://lh4.googleusercontent.com/-6...316_215933.jpg

https://lh3.googleusercontent.com/-2...324_190219.jpg


mowe

https://lh3.googleusercontent.com/-z...324_190402.jpg

https://lh3.googleusercontent.com/-X...324_190348.jpg

#12 laser110 Mar 27, 2013 12:56 AM

Looking in my 97/98 Robbe book it shows that they recommened then a 2X model 4470. Cross refrencing 4470 is Power 700/ 13 T motor. 13 amp motor.


In my Happy Hunter I am using 2 Navy EF 76 II which give me a nice burst of power and speed when I need.

Scott

#13 Willj Mar 27, 2013 04:40 PM

That is one gorgeous model. What do you think. Is it worth the price? On checkout at Robbe it came out to about 2,200.00 Canadian. And then there is the shipping of it. Holy Smokes!
It seems a little over the top in price.

#14 dobydog6507 Mar 27, 2013 05:59 PM

Quote:

Originally Posted by Willj (Post 24551161)
That is one gorgeous model. What do you think. Is it worth the price? On checkout at Robbe it came out to about 2,200.00 Canadian. And then there is the shipping of it. Holy Smokes!
It seems a little over the top in price.


If you don't mind building in wood, buy a Dumas American Enterprise for around 150 bucks....more or less the same style of boat.

#15 pompebled Mar 28, 2013 11:56 AM

Quote:

Originally Posted by rakec (Post 24511694)
guys, i am stuck with a problem. i try to run my boat on the water, 2 motors on one esc, and the motors are vibrating as hell. i try to change the aligment and the aligment is perfect. vibration is very noisy. how can i silence that down?

Hi Rakec,

What does vibrate? Only the motors, or the entire drivetrain?

In one of the pictures I can see the couplers and a rather long piece of unsupported shaft, how long is that piece and how true are your couplers?

It's very well possible there is a resonance building in the unsupported shafts.

I assume you did fill the stuffing tubes with light grease?

Regards, Jan.


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