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[ADIJohn65]

Hello All

Just looking for a little help im looking for a motor for my MMM brackengarth i am going to run a 100mm kort prop and looking to make a good towing tug. I have looked at the motors MMM sell but had a few bad comments regards power so not sure what to use any advice would be much valued.

Regards John

[HS93 (RIP)]

these are good at the price, they are a 900 type motor as sold by some traders bit some are a bit  scruffy they run well

http://www.ebay.co.uk/itm/12-v-ELECTRIC-MOTOR-12v-PRICE-INCLUDES-POSTAGE-/300511267976?pt=UK_BOI_Electrical_Components_Supplies_ET&hash=item45f7de0c88

Peter

[Tug Fanatic]

these are good at the price, they are a 900 type motor as sold by some traders bit some are a bit  scruffy they run well
Peter

Will these really turn a 100mm prop at a sensible speed for a prop that size on 12v? I would have thought them too fast unless geared which makes them much less of a bargain.

[787eng]

I have looked at the motors MMM sell but had a few bad comments regards powerRegards John

Pictured is my Imara doing a bit of towing with two MMM T12's
Pray tell what power problems?

Puzzled
Mark

[Netleyned]

The foremost tuggers in the country are not
Selling anything but the best tug motors

Ned

[ADIJohn65]

Thank you all for your comments

      Looks like i will be ordering a MMM T12 or T24 motor would you all think a action electronics set up will work well with this motor?

       Regards John.

[787eng]

Good decision
I've experimented with Brand A and Brand M. By far the best setup I've found is the Electronize FR15 series ESC with the T12
Great low speed control  and all the torque at the top end...

Mark

[Andyn]

Overly power hungry motors that are actually quite inefficient. The price is unjustifiable too.

Suit yourself

[Kim]

Overly power hungry motors that are actually quite inefficient. The price is unjustifiable too.

Suit yourself

That’s a  bold statement! Perhaps actual fact, an alternative suggestion or statement of allegiance may give more credibility.
Kim

[Stavros]

alternative would be a Graupener 900 or equivelent

Dave

[Andyn]

alternative would be a Graupener 900 or equivelent

Dave

Exactly what he said. But without the spelling mistakes

[Stavros]

 Comments like that Andy are personal and totally uncalled for, does it matter that there are spelling mistakes,or even grammatical ones , not impressed young sir


Dave

[Kim]

So you offer as an alternative this ? According to Cornwall model Boats -

Single ballraced, 12-pole armature.

Special high-performance motors with integral
suppressors. Characteristic high torque at low rotational speeds, therefore ideal for use in direct-drive model boat power systems with large
propellers.

Specification
Nominal voltage 12 V
Operating voltage range 6-40 V
No-load rpm 6500 min–1
No-load current drain 1,1 A
Current drain at max. efficiency 8 A
Current drain when stalled 54 A
Max. efficiency without gearbox 71 %
Length of case, excl. shaft 85 mm
Diameter 51.5 mm
Free shaft length 15 mm
Shaft diameter 6mm
Weight 645g

Hmm...  Are we comparing like for like? You claim to know

[Stavros]

Yes I do, Have you a problem with this,it seems to me that you do or is it a probem with Me

 I see you have NOT critisied HS93 recomendation at all.


So come on EXPLAIN yourself Sir


Dave

[Kim]

Stavros,

If you mean Hs93's recommendation then the figures don't tally with a 900 motor. Noted Below -

12 v electric motor. 

Motor spec:-

Body:                           52mm dia  85mm long

Shaft:                           single end 5.0mm dia ballraced

Commutator:                 12 pole, low noise

Voltage:                       12v DC

No load RPM:               6700 1.2A

Max efficiency:             5250rpm, 1500g cm, 80w, 6.5A, efficiency 55%

Max power:                  3200rpm, 3500g cm, 115w, 9.5A

So we are just arguing for the sake of it? looks to me as if we have 3 different motors now. Personaly i like the T12's and have no issue with them. 

[Stavros]

SSSHHHHH don't tell everyone,But I will tell you something

Those are the same motors,and thats come from someone who has stripped then down to see whats in them and NO it wasn't ME but someone who works in the motor industry who wanted similar powered motors foe a client of his,Yes the shaft size quoted is different but in truth it is not as I have some on my work bench at the moment.

But I dare say you will say differntly but do I care well not really I know what is fact,there are only a handfull of motor manufacterers in the world who make this kind of motors,and you would be surprised actually how many there actually  are.In truth many claim to be manufacterers but are in Fact only suppliers



Dave

[Kim]

Thank you all for your comments

      Looks like i will be ordering a MMM T12 or T24 motor would you all think a action electronics set up will work well with this motor?

       Regards John.

My answer is probably yes ... but i have no experience of Action gear ... Personally i use Electronize as most of my boats are scale and i like the low frequency setting in their speed controllers.

I'm sure someone more understanding of speed controllers will be able to advise.
Regards
Kim

[unicorn]

 

        Whose 100 mm prop is it?  --  if its a Robbe  or Prop shop  --  then their reccommendions would be in
  region of 1000 to 2500 rpm --  so a low revving high torque or a good geared motor would be the answer.

              ask the experts  --  you know it makes sense.

                                                                       rgds unicorn

[Kim]

SSSHHHHH don't tell everyone,But I will tell you something

Those are the same motors,and thats come from someone who has stripped then down to see whats in them and NO it wasn't ME but someone who works in the motor industry who wanted similar powered motors foe a client of his,Yes the shaft size quoted is different but in truth it is not as I have some on my work bench at the moment.


Dave

Dave a wee pic for you...  

        Whose 100 mm prop is it?  --  if its a Robbe  or Prop shop  --  then their reccommendions would be in
  region of 1000 to 2500 rpm --  so a low revving high torque or a good geared motor would be the answer.

              ask the experts  --  you know it makes sense.

                                                                       rgds unicorn

Ahh..... now were getting somewhere ...
I have recently spent £100's of pounds in trial motors of similar rpm... not easy to come by and not cheap... surprise!

i will be listing them soon ... as soon as some rather knoweledgeable guys have a play with them.. and give their aproval / disaproval...

Let the record show i'm Kim from Clyde Model Boats incase there is any confusion on my interjection to this discussion.!

[Tug Fanatic]

Unless you have lined up your pictures exactly with the grain of the desk "wood" this is surely the same picture twice?

I haven't seen a 6000rpm 900 series motor that will turn a 100mm prop sensibly. You need to gear it.

[HS93 (RIP)]

I should of said in my post that I would have geared it 2 to 1  using T5 gears and belts from Tecknobots, I tend to gear ALL my motors so as I don't need to mess with water cooling and do away with couplings, I do not find them noisy at all , toothed gears can be though but at these revs not really a problem.

Peter

[CF-FZG]

Comments like that Andy are personal and totally uncalled for, does it matter that there are spelling mistakes,or even grammatical ones , not impressed young sir

He's right though, why people are too lazy to use a spell checker beats me - it's right below the box you type your reply in, so why not use it



Mark.

[Tug Fanatic]

I am even more dismayed by people who do not punctuate correctly by ignoring the need for question marks, full stops and sentences.  

If only we were all perfect!      

[CF-FZG]

I am even more dismayed by people who do not punctuate correctly by ignoring the need for question marks, full stops and sentences.  

Only 1 sentence, no question was asked - I'll give you the full stop though

[Tug Fanatic]

He is right though. Why people are too lazy to use a spell checker beats me as it is right below the box in which you type your reply. Why not use it????????????????????????????????????????????????    

The truth is that very few people write good English. Even fewer understand punctuation. We can all get very aggravated about this but I really don't think that it is important as long as the meaning is clear.

We are way off topic.        

I am interested in you use of of T5 gears. How small can you go with the size of the motor pulley before problems arise? Do you use aluminium pulleys? I am hoping that you use toothed belts as I have used "O" rings for many years and am trying to get away from the sideways load that they put on the propshaft bearing.