Model Boat Mayhem

Technical, Techniques, Hints, and Tips => BRUSHLESS Motors and Speed Controllers => Topic started by: portside II on March 31, 2012, 09:37:20 pm

Title: suppose i wanted to make a club 500 brushless
Post by: portside II on March 31, 2012, 09:37:20 pm
I am thinking of buying a new club 500 to go with the one i have allready , but as it wont be for regulation racing i thought about going brushless . Yes i know it's not allowed acording to the rules , but i dont want to live by the rules all the time :} .
So as i know nothing about brushless stuff what would i need , all this kva etc stuff is over my head .
daz
Title: Re: suppose i wanted to make a club 500 brushless
Post by: knoby on March 31, 2012, 10:21:00 pm
club 500's already run about as fast as the hull design will cope with, so fitting a brushless will cause handling problems. However, like you, I'd just see that as a challenge not a problem.  Have seen a 500 with 3250 kv in it & its fast, but it didn't steer well, it had trim tabs & turn fins fitted, but still just wanted to lay on its side & go straight on.
An alternative would be to fit a small brushless, say 1100 kv, which would give same time but much longer run times.

Good luck
Title: Re: suppose i wanted to make a club 500 brushless
Post by: Andyn on March 31, 2012, 10:41:03 pm
It won't cause handling problems if you fit an equivalent brushless motor to a brushed 540?  %)
Title: Re: suppose i wanted to make a club 500 brushless
Post by: nick_75au on April 01, 2012, 01:55:52 am
And again someone with all brushless motors are too powerful %)

A "stock" 27 turn 540 motor is around the 2300Kv to 2500Kv range, a smaller 480 case brush-less in the same range will give equivalent power and a "540" canned brush-less will be more powerful so a larger prop could be used

Kv is just a rating to determine the RPM of the motor that is all.
Kv times battery voltage = no load RPM, brushed motors do also have a Kv rating.

Kv and watts (the power of the motor) determines the size of the motor.
Nick
Title: Re: suppose i wanted to make a club 500 brushless
Post by: knoby on April 01, 2012, 09:58:25 am
Again someone who dosent read my posts properly  ;)

So, if you want to go the same speed as a brushed 540, why not just use a 540.
If you want to go quicker than a 540, be careful because the hull is already running close to its limit, so you will start to get handling problems, which can be overcome, but not without a lot of effort,
The alternative is to use the extra efficiency of a brushless motor to give you equivalent speed but much longer run time.

But as the goal of fitting the brushless wasn't stated, I thought it best to give a few options & try to find out exactly what Daz was wanting to achieve,
Title: Re: suppose i wanted to make a club 500 brushless
Post by: portside II on April 02, 2012, 04:15:17 am
some interesting replies there , thank you guys . Three reasons for trying brushless ,
1, because i have never used brushless before
2, to get a bit more speed from the hull
3, to get more duration ,run time

#1 is simple #2 it seems that the hull/ motor design is at its optimum , and #3 still thinking about that.
So it looks like an equivilent motor to the recomended 540 which if i have got it right would be a 2,300/2,500 kv motor ,
running with the correct esc ,and possibly a larger prop . as for the duration if i was to use a 2c lipo pack of 2,500 ma would this be suficcient , this is where i fail as i dont realy know , and i don't realy want to spend / buy the wrong gear .
I have seen motors at £20. and £100 and then you still have to buy the esc battery and then the charger, if i don't know i could be waisting money, so what , from where and how much please.
daz
Title: Re: suppose i wanted to make a club 500 brushless
Post by: nick_75au on April 02, 2012, 10:38:32 am

#3 is easy
Is a Club 500 normally restricted to Ni-XX batteries, if so this or equivalent is very similar weight to a 3300 mAH Ni-mh with more mAH

http://www.hobbyking.com/hobbyking/store/__8578__ZIPPY_Flightmax_5000mAh_2S1P_20C_.html , for the penalty of 50 odd grams a 6000 mAH will give even more.

More speed means higher loaded RPM, the efficiency advantage of a brush-less will mean an equivalent Kv and power (watt) brush-less will probably be faster, higher loaded RPM will mean higher amps regardless of motive power on the same prop.

The motor would need to be that Kv and about 150 watts to be equivalent.

http://www.hobbyking.com/hobbyking/store/__17730__XK2860_B_2200KV_Brushless_Inrunner.html

Its 500 watts ( will only draw what the prop asks) but only 28 mm diameter as opposed to 35 mm and 64 mm long as opposed to about 57 mm and similar weight.

Hull form issues are less in my area of knowledge.

Nick