aluminum heatsinks?

[Impreza]

Anyone try the perfection aluminum heatsinks at toyeast? Are they worth the purchase?

Impreza :smiley16:

[spanky]

humm im still torn on the benifit of a an alum heat sink.. even with a dual cell my motor never even gets warm… IMO the heat sink is just a marketing ploy to make more money by selling more accessorys…

Custom bodys: Ferari 250 GTO, 69 doge charger, Micro Cooper, Beemer 320i Turbo, Baha Beatle, New Beatle Rsi Porche 911
email: custombitbodys@attbi.com
website: http://custombitbodys.home.attbi.com

[kevsta]

I too have also wondered about the heat sink and curious on whether it worked or not.

With a cpu, the heat sink covers the entire surface of the cpu with thermal paste in between.

When you look at the heat sink on a tomy bit, it only touches a portion of the motor, so I’m not sure how and if it really works in dissipating the heat from the motor.

Perhaps someone else know more on this…

Cheers,
Kevin

[Lazboy]

well the idea is that metal transfers heat very quicky and the bigger surface area it has to get rid of the heat the quicker it will cool down

as to if it really works on a bitcharg is a big question because most likey does get that hot allthoght is does weight more than the aluminiom one so the 0.1 gram or so might make a sighlt diffrence but it probley better to give the money to charity

________________________________________________________
CompactChar-G 40Mhz S2000 range mod, spring suppention
Bit Char-G 57mhz Booster Fairlady Z
MINI Z Wrx WRC 2000 This thing RIPS

[barto_85]

I think Barrell sells these, ask his opinion.

[micro_Amps]

If you look at the internals of a motor, the ‘windings’ that carry the current are the part that gets hot.
These are spinning on the shaft, around the magnet which is in the center.
The only way for heat to be transferred out of one of these motors is for it to first warm up the shaft, then radiate the heat thru the magnet and into the external casing. (Or by radiating directly from the windings accross the air gap and into the external casing.) By the time all this happens a motor under extreme load or voltage will die anyway.
I dont think a different heatsink design will really benefit the cooling of a motor, but……
they look good, especially the black and the gold ones !
One way I can see to cool these motors is to pull them apart, drill a series of tiny holes in the casing and put them back together again. The spinning armature will push air thru the case and cool it. (Well thats the theory anyway)
These motors are reasonably difficult to stip and rebuild so if you are going to try it be very careful, and expect to destroy a few in the process.
:)uA

[PandaBear]

What % of total car’s mass is the std heatsink?

If the original is hefty steel, an aluminium one might be lighter. The Bit Racer also has a skimpier one too, less material on it.

[ph2t]

Impreza, they are purely eye candy man. I doubt there is any thermal transfer going on that would benefit the motor……… If anything, my Bensu clone heatsinks are better, they wrap around the motor in a more circuilar pattern which increases the area of contact…..

[Barrelll]

hey, well i have one running in my 3.8 motor car, im not expert, but im guessing the cooler the engine, the better the performance, and a greater life of the motor.

They do look very cool, the black and gold ones, so hey if u want one, buy one !

27MHZ 3.5 Honda Accord (Custom Exhaust and F1 Wing)
35MHZ 1.0 Battery Modded Castrol Supra
45MHZ 2.2 Custom Painted Yellow and Black WRX
57MHZ 2.6 Booster Trueno
Mini Z Blue WRX (Lights, Gold alloys, Exhaust)
Mini Z Castrol Supra + all mods (Coming)

[barto_85]

you forgot your link barrell, but i guess everyone knows it by now. http://www.bitchargoz.tk/
look at that, i did that from memory.

[ph2t]

Barrell, I’ll say it again. They are eye candy. I doubt they cool the motor any more that the regular heatsink. If you realy want a better thermal response put some silicon grease in between the motor and the heatsink (avail at any electronics shop, Jaycar, Dick Smith, etc….). They say that these sinks are more aerodynamic, that’s crap! They are located within the shell of the car and not on the outside so I doubt that there’s any airflow around them at all.

The best suggestion is Panda’s and the % weight issue of the old sinks .vs the new…..

/…end rant…../

ph2t.

[Impreza]

Thanks all. Will most likely save the money and use it on a 3.8 motor instead.

Impreza :smiley16:

[z-beam]

the use of the word is fair because the design has taken considerations to allow for the flow of air around the motor, which makes them “aero dynamic”.

also a bit(s2000 compact) weighs approx. 28g’s or exacly 1 ounce out of the box, and a heatsink weighs…..

this is odd, a heatsink (standard) varies between .3 and .5 of a gram!!! thats a shok!
the cuved (heat reactive kit racer) heatsink weighs .6 (the .3 was probably a kit sink.)

compact 2.2 is 1.3g’s
others weigh 1.2g’s

panda and ph2t, do you reckon the steel sink saps tranfered current to the motor via the casing? could an aluminium one eliminate the electrification of the metal parts in contact causing minute e.m. interference?

i got scales so if you need some more info to further the quest of perfect bit theory just ask!!!

[micro_Amps]

The material that the heatsink is made of would make absolutely no difference (electrically) to the running of the car.
:)uA

[z-beam]

is this cos its the earth end of the curcuit?

[jamiekulhanek]

It’s because the heatsink has nothing to do with the circuitry, the current enters the motor through the tabs under the motor, and on the endbell, I think the heatsink thing is a negligible, as the motor’s case would have a larger area (if ya rolled it out) than a heatsink, to me its just a clip that holds the motor in, anyway, even with a dual cell mod the motor barely gets warm anyway.

If life is a waste of time, and time is a waste of life, then let’s get wasted and have the time of our lives!!

[PandaBear]

Quote:

panda and ph2t, do you reckon the steel sink saps tranfered current to the motor via the casing? could an aluminium one eliminate the electrification of the metal parts in contact causing minute e.m. interference?

Steel? Or is it Copper…?

This reminds me of a previous thread with
Mr Lancer Evo (bless his missing soul).

Here:-

Metal Conductivity 10-6 cm-1 Ohm-1
Silver 0.63
Copper 0.596
Gold 0.452
Aluminium 0.377
Rhodium 0.211
Iridium 0.197
Tungsten 0.189
Zinc 0.166
Nickel 0.143
Ruthenium 0.137
Osmium 0.109
Iron 0.0993
Platinum 0.0966
Palladium 0.095
Tin 0.0917
Lead 0.0481

There’s a slight difference in conductivity, so if you want the
ultimate heatsink & current conductor you’d use Silver.

[jamiekulhanek]

Quote:

Quote:

panda and ph2t, do you reckon the steel sink saps tranfered current to the motor via the casing? could an aluminium one eliminate the electrification of the metal parts in contact causing minute e.m. interference?

Steel? Or is it Copper…?

This reminds me of a previous thread with
Mr Lancer Evo (bless his missing soul).

I remember that thread like it was yesterday, we all know the best conductor is diamond 🙂

If life is a waste of time, and time is a waste of life, then let’s get wasted and have the time of our lives!!

[z-beam]

man dont compare what i said to lancer!
remember HE KNEW! i was merely asking.

thanx panda for the list, i was led to believe that gold was the best conductor cos of all the music equipment that uses gold plating for contacts.

diamond? xpensive. forgot electricity flows along the shortest route possible:blush:

panda would it make any difference to performance if you plated the motors contact with silver (or gold) as well as the contact tab the motor sits on?

[jamiekulhanek]

The current that flows through those tabs is very small, i doubt it would make any difference.

If life is a waste of time, and time is a waste of life, then let’s get wasted and have the time of our lives!!

[8ch Ess Vee]

The current that flows through the tabs surely is the full motor current draw. So theoretically the lower the resistance between the PCB and the motor the better the performance would be.

Oxidisation, even a greasy fingerprint can be enough to increase the resistance of the contacts. In an ideal situation you would have a soldered connection between the conductors from the PCB and the motor case. Obviously this is a fairly dificult thing to do, but perhaps not imposible.

The cross sectional area (greater CSA = lower resistance)of the wires from the PCB to the tabs is relatively small so there may be minimal gains made by increasing the size of those wires.

As you said Jamie, the current is small, and I guess that in the big scheme of things it is. I’m an Electrician – Instrument tech by trade and regulary work on BIG industrial gear, with electric drives up to 3000 hp, so these are small yes.

The batterie/s in a Bit are only rated at what 100mAh up to perhaps 200mAh, that is milliamps per hour. So if I remember correctly, the battery in theory will deliver exactly that, 100mA for 1 hour at its rated voltage.

The PEAK amount of current available from the cell/s is actually MUCH higher. Short out a batery and tell me how hot it gets!! A lot more heat than 100mA will give yo thats for sure.

So if the motor is the item that draws the most current then improving the supply to it should make it go better.

If you look at say the 1/10 scale electric cars, most of them run say a 1200mAh (1.2 Amp) 7.2v pack, but the Electronic Speed Controllers are often rated for currents up to around 80 amps. And those cars never run for an hour. 5-10 minutes would be a good run for some of them. Likewise, a Bit doesnt run for an hour so it definately draws more than 100 – 150mA.

Gold plated contacts would improve things marginally, so would a gold plated motor, both plated, even more again I’d guess. Even tinning the motor case and the contacts with solder may improve the contact area and give you minor gains.

Whatever you do, the improvements would be fairly hard to distinguish over standard.

8ch Ess Vee
_________________________
Turkey Hill Raceway http://community.webshots.com/album/64812360tweTQI
Compact Char-G, White R34 GTR 27mHz
2 x Nano Racer Clones
Micro Super Charger, Black WRX 27mHz

[z-beam]

thanx 8chsv

[8ch Ess Vee]

Not a problem!!

[Efarel]

Hi,
in my opinion the alu heatsink is simply more rigid than standard steel one.

Efarel

[Author]

Posts