Model Boat Mayhem
The Shipyard ( Dry Dock ): Builds & Questions => Working Vessels => Topic started by: Stavros on June 03, 2007, 06:03:19 pm
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Now having just acquired one of these lovely tugs what I want to know is what motors to fit as at the moment it is fitted out with MFA 500 geared 2.5.1 coupled up to the original white metal props,with this set up th performance can only be described as PATHETIC I ran these on a 12v 7amps batt so they were getting plenty of power fed to them ,any suggestions as to set up and props and please don't suggest prop shop for props as they are a swear word as far as I am concerned cheers Stavros
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Stavros dont know if this will help but Model Slipway do the motor set for the Yorkshireman:
Pack 1 540 motor (4.5-15v) w/ gearbox 6:1 (best on 12v) = £20
coupling = £6.50
£26.50
You will of course need two of these.
http://www.modelslipway.com/york.htm
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I think the motors MSW supply for Yorkshireman are the MFA500 geared at 2.5:1!
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Stavros,
The motors with 2.5:1 gearbox are best run on 6 volts. If you wish to run on 12 volts it is advisable to use the motors geared 6:1 as DickyD suggested.
We usually stock brass propellers but unfortunately we are out of stock at the moment. However, Barry at Westbourne Model Centre will be able to supply suitable ones. Tel: 01202 763480. Email: saleswestbourne@btconnect.com
Hope the above helps.
Jackie
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Hi Stavros,
Firstly, ditch the props and buy decent ones
I have recently finished my Yorkshireman. When I started the build in 2002 Model Slipway supplied 2 x 6v 2.5:1 belt drive motors. After recovering sufficiently from the stroke to continue the build I contacted Model Slipway and they supplied 2 x 12v 540s with 6:1 integral gearboxes. I run these on a 12v 7ah battery and the model performs very well. Initially I ran both motors through 1 ESC but now use 2 x 15amp viper ESCs and a viper mixer unit.
On a good day she dances in our pond
Hope this helps
Tom
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Excuse me is it mee being stupid(carefull on he replys !)but if you run the motors on 6v the boat would go slower ???,Jackie thanks for that I will contact Westbournes,If I use the 6:1 motors suerly it will go slower or is it me being silly.I know thta no tug is meant to be a speedy boat but? Stavros
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The motors with 2.5:1 gearbox are best run on 6 volts.
If you wish to run on 12 volts it is advisable to use the motors geared 6:1
You are using MFA 500 geared 2.5.1
Model Slipway suggest 540 motor (4.5-15v) w/ gearbox 6:1 (best on 12v)
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Thanks for that Dicky d but read my post previous to yours
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Stavros,
If the Yorkshireman is anything like the Aziz, you use the 2.5:1 gearbox on 6V or the 6:1 gearbox on 12V - according to the MFA site the 2.5:1 gives 3000RPM at 6V and the 6:1 gives 2633RPM at 12V. So.....ISTM that what you want is a drive system that delivers 3000RPM at the prop.
Wom
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Stavros you are right of course and I cant tell you why 6v is better than 12v, but it doesn't really matter because according to Model Slipway you are using wrong motors anyway.
Maybe with that gearing 2.5:1 they are just more efficient on 6v ???
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THe main difference is the power consumption - 7W on 6V and 21W on 12V
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THe main difference is the power consumption - 7W on 6V and 21W on 12V
So if we have 7W at 3000 rpm and 12W at 2633, where is the extra power going ? Does this mean that at 12v it should have a bigger prop ?
Don B.
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Welcome to the wounderful world of electric motors - the extra power may not be being delivered to the prop, and the power consumed on 12V may be less than indicated, though this is the figure off the data sheet. The extra power is being lost because you are swinging the armature of the motor twice as fast - therefore your kinietic energy is four times greater - also your frictional losses are much greater.
Whether you canuse a bigger prop on 12V depends on the torque curve of the motor - it will only work if there is enough torque to turn the prop at that speed in the water. If not all you will end up doing is disspating more heat in the system.
If I understand it correctly, there is no point in having more torque than is needed to swing a prop in water at the required speed as that extra torque is wasted. You may find that the higher voltage is less efficient when driving a bigger prop.
Wom
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Hi Stavros,
Further to my earlier reply.
I still have the original 6v motors . They are geared toothed belt drive and I found them a pain.
I ran the boat with the original motors then on the replacement 12v motors - before fitting the mixer - It may be subjective but for me the boat runs far far better on 12v. As for speed, Its a tug! mine goes as fast as I want it to.
Good luck with whatever you decide to do but may I suggest you ask Model Slipway what they advise.
Regards
Tom
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Model Slipway have aleady told him on here.
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Fair comment Dicky d having spoken to Jackie today all she can suggest is what she suggested all they are interested is scale speed they could not reccomend an alternative .Personally I can not see dropping from 12v to 6v will work for the simple reason the motors will run slower common sense tells me that and if that is the case well it will go slower but maybee that is the so called scale speed,if so what a load of Pooh Pooh as any slight wind on the lake and it will go backwards.To heck with it I will fit some MFA 850 then it will have the power and when not needed will also go at so called scale speed!!!!!!!!!!!
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Stavros, what you need are double hamster treadmills on each shaft consuming best quality millet delivered through 3/8th inch tube fed from a mini silo in the superstructure. This will give you a genuine running time of one hour. If you need more power then a couple of squirrels could be substituted but these should be swapped out within 40 minutes before they bite through the hull. Alternatively, just do what Jackie suggests.
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Stavros reading back on this item every one says to use 2/540 motors (4.5-15v) w/ gearbox 6:1 (best on 12v). Tom has these in his and says they are fine so why go for something different.
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Stavros,
The geared 540's are an equivalent to Deccaperms, but more torquey.
I would see what ballast she requires before deciding on 6 or 12 volts.
As you know she will take some ballast to get her down to her marks.
Bob
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Dickey d simple m8 when you sail on a PROPER lake what I mean by a PROPER lake and not a paddling pool you would understand why I need power.The lake I sail on is over 2miles long and 1/2mile wide and is very prone to wind so windage on tug versus poor performance motors(scale speed indeed)with this in mind now can you see why more power is needed,also If I need to tow anything power is needed it is after all a tug!!!!!!!!!!!!!!!!!
Shipmate 60 how the devil are you dried out yet??? as far as ballasting is in the question,on 2x6v rides too high 1x12v spot on know of any 850 going cheep!!!! those should give enough power don't you think.
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To be honest mate the motors on 12 volts will be powerful enough.
I had a 550 geared 3:1 in my girl class tug with about a 70mm prop and she would plane.
If necessary up the prop pitch, but the motors should only pull 1-2 amps each, so plenty of duration.
have you got a boot full of 12 volt 4 Ah batteries yet for your patrol boat?
Bob
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Working on the batts Bob trouble is with the yorkshireman is the size of both the props,small!! fair comment I understand what Jackie has said but scale speed does not mean a thing if you are fighting against the wind towing another boat!!!!! as you well know you need POWER me will have to have a serious think about this ;)maybee a pair of motors from the Happy Hunter or even a pair of 777's!!!!!!!!!! Stavros
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Sorry Stavros didn't realize you wanted to water ski ;D
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Hi Stavros and Dicky d
I can see which side of the pond you are both coming from
Dicky d where the kit states 540's with gear boxes to suit 6 or 12v thats fine if you want to sail around at scale ,i cant see anything wrong with that.
Stavros you are thinking like me give it some beef drop the tourque'st power plants you can find in with a pair of props big enough and with as much pitch as you can to pull the landing stage your stood on across the lake , in my Brakengarth i have the original motor and prop recommended from M.M.M. (they know about tugs) and at full chatt she creates an enormous bow wave and wake as she ploughs across the pond but with a tow the power is there for some scale towing .
Tugs ain't designed for speed and neither is a tractor ,but who would have thought 20 years ago that a tractor would be doing 50mph+ down the road (JCB fastrack)
daz
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Hi Stavros
I run the Ormesby Cross on two MFA 850s direct drive. She performs great, with lots of power. I think they will be too fast for the Yorkshireman as the Ormesby weighs 54lbs fully ballasted.
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I must jump to Stavros' side here. The tug was clearly underpowered when he was sailing it last Sunday. (OK maybe it was just scale speed.) That day the weather was reasonable but he is right when he says that it just would not cope with the conditions which we sometimes encounter.
I have a Northsider fitted with the largest motor that MMM supply driving a 115mm prop (yes its HUGE) running on 18 volts.
Sometimes when the wind is coming off Snowdon and being channelled down the valley along the lake, I need all the power available to make good headway against the wind and waves. The waves alone are difficult to power through and water can be flung up and over the boat as high as the funnel !
Most of the other boats have to creep up the bank to make headway. Stavros is right - with the recommmended setup the boat would be blown backwards at those times.
I would not claim to be knowledgeable on the technical bits of voltage - all I know is that the Northsider on 12 volts does not perform as well as it does on 18 volts. On 24 volts it is just too powerful.
Don B.
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Stavros,
You saw my Schutze at Mayhem, she has 2 x 777's in her and 4 blade 35mm props.
If you want your tug to keep up with her go for them, hehehe :)
12 Volts a bit too fast, 6 volts pathetic.
Bob
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Stavros,
Check this link on ebay for Yorkshireman motors.
http://cgi.ebay.co.uk/R-C-Yorkshireman-Odyssues-Twin-Screw-Tug-Ready-To-Sail_W0QQitemZ110132478994QQihZ001QQcategoryZ140971QQrdZ1QQcmdZViewItem
Bob
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Now thats interesting Bob as I have just come back from routing in the shed and found 2 identical johnson motors mmm Stavros
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and runs on 6 volts too.
Bob
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Stavros,
If they are the motors I am thinking of they free rev at 6 volts at 9000 rpm.
Dont even think about 12 volts.
Bob
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No mickey taking intended Stavros. I apologise.
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Thank you DickyD for being man enough to appologise Stavros
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So what motors and props you going with?
Bob
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Ok Bob what are you doing home you supposed to be at sea!!!!!!!!!!!!!!!! As for motors the jury is out on this one due to he fact I am awaiting new props and having read teh bumph on mfa motors wiht the ratios of 2;5;1 and 6;1 the rpms are nearly the same on 6v and 12 so I cant see the point in using them.As for 850's the prop angle is totally wrong for them due to the wood thta has been bonded to the hull,so me has to think,Having also looke dat 540's they dont deem to rev much better so i thnk I will have to look at poss hte motors out of the Happy Hunter possibly or the Graupener range.Yes of course I realise thta no tug is a speedy boat BUT one does not have to sail flat out all the time does one!!!!!!!!!!!!!If I can get something to give me say 8000+rpm on either 6or 12v I would be quite happy as I can throttle back but when I need the power for towing or beating the weather conditions at least I will have th power to do so If you gte what I am trying to say,boy if you can please let me know asap! stavros
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Hi Stavros, Sent you a PM.
John. POLL
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Hi Poll no pm as yet
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Hi Stavros , Writing as someone who has built a Yorkie may I offer the following advice. As stated before the white metal props are not suitable , I obtained my brass props from Model Slipway when I ordered the kit , I read they are out of stock so I would reccomend George Sitek . I experimented with various combinations of motors and found the best performance / running time was obtained by using a pair of Protech Mega X 720 BB Torque motors model number ME72102. These are direct drive and do not require a gearbox . I run these at 12 volts from a 12volt 7amp battery . These motors may be obtained from 308 Hobbies London for £18 each or Sussex Model Center for £12.80p each. Hope this is of use.
The Ships Cat
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Hi
I'm running my 540 1:2.5 motors at 12V in my Yorkshireman. I can only reccomend to use 12V as a ESC can adjust the speed anyway. No one tells you to run the Yorkshireman at full speed all the time. An other advantage using 12V no matter what motors are installed, is that the resistance in wirering and insde the ESC ect. is becomming less important than using 6 V. Thats also the reason why you local powerstation is using high voltage and you need to transform it to lower voltage.
So using 12V will give you a bit more Wh to the motors and less waste in heating losses.
Regards,
Tom
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By the way, I have chosen to use 20 PC of 1.2V /10.000 mAh NiMh batteries.
I had several 12V/7 Ah Pb Acid batteries, but I have never been able to measure higher capacity than 5.5 Ah on NEW cells. Comparing weigh and capacity I get double capacity and half weight by using NiMH and they have a much longer lifetime too. So my Yorkshireman has now 12V / 20 Ah inside, at the same weight than a normal 12V / 7 Ah acid would give me.
Only issue is that price is also x2 for the NiMH cells
Regards,
Tom