RC helicopter size/class confusion

[jperkosk]

Any brave heart to try to clarify the issue ?

Nitros are easy, they go by displacement, 50-size being 0.50 cin (8 ccm) and so on.

Electrics are a mess, some seemingly go by the motor size (in Watts?), others by blade length, and Esky classifies Belt CP as 600 sized . Why do I think it's a 450-size heli?
I suspect the electric motor on some original heli of this size was 450W.

And in my 600N, what does the 600 stand for? It's not an equivalent electric motor size, I'd like to see a 600E putting around on 600W motor!!! So I think it's the blade length here.

Funny thing, I think that Esky is (accidently) on the right track here trying to classify the heli size by the rotor disk diameter, but it's really their marketing trying to confuse the beginners into thinking they're buying a larger helicopter, so they should get no credit for this accidental effort .

So again, is anyone up to the task of bringing some order and/or cross-reference to the classification?

[Jonnyheli]

Esky just copied Align and so did the clones. I'm not sure why Align chose 450 for that size because the blades are only 325mm... I'm no expert on this, I'm sure Raf could tell you where they got the numbers. But I think it was Align's fault we now all call the 325 a 450? Same with the Trex 500, that has 425, weird.

Different companies just state the sizes differently. For example logo go by blade length. The logo 400 supports 425's, I think they just round off the numbers to make it tidier.

.50 helis usually use 600mm blades, .90s use 700mm so there's some correlation there too.

I think that different companies will have different methods for them coming up with it's name. It's name doesn't nesscesarily have to suggest it's size class. You class them which ever way YOU want.

Jonny

[redbird300]

Align screwed the whole thing up. Story is that their first 450 had a 450 Watt motor, but they were too shortsighted to see that technology might change, lol. True or not, that number is meaningless now, and some inpirationles other manufactureres followed the example, too bad, that's why we have all the confusion now.

Before Align, most brands were using a logical and meaningful way to name their helis. Like the example of the nitros that you mentioned. That's clear. Mikado did it with the old Logo 10 - 14 - 16 - 20 - 24 series, with that number indicating the number of NiCad cells. After that, they went for main blade range: a Logo 400 = 400+ mm blades, Logo 500 = 500+ mm blades, etc... Thunder Tiger never played that game either, at least you know with a Mini Titan E325 what blade size it has. None of the older manufacturers in fact, for as far as I know. Like Century helis, and there must be others. Thank God we have Align to make it a bit more complicated.

[CyprusDave]

Before brushless motors, the most popular brushed motors were made by Mabuchi, whose motors were given code numbers, all of which had a particular meaning

http://www.mabuchi-motor.co.jp/en_US...ic/t_0302.html

My understanding is that the original 450 size heli was called that because it used a Mabuchi 450 motor. Just for interest, the brushed motor in an E-Sky Lama coax is a 180 size, and the Big Lama is I think a 380. Another common size in early electric RC model (cars and boats) was the 540 size (hot stuff in it's day!)

Of course now this is all history, and as Jonny says, companies use whatever method they choose, although the blade length is maybe the most common (at least for 600 and over, although some do use it for smaller sizes as well) and probably makes the most sense.

EDIT - TBH I don't believe the story of the first T-rex 450 having a 450 watt motor. Even now a stock 450 Pro only has about a 350 watt motor, and back in the early days, there would not have been a battery capable of running a 450 watt motor.

[Jonnyheli]

Originally Posted by redbird300

Align screwed the whole thing up.

That's what I thought. Just wasn't sure on why they chose 450. Now I know

Again there are no 'standards' set when naming helis. The way to tell is to just look at the specs of the heli, look at engine size or blade length...

Jonny

[redbird300]

Interesting Dave. And look what I found here http://en.wikipedia.org/wiki/T-Rex_(RC_helicopter). As I said, I don't know the whole history, just trying to add some bits and pieces of information.

"The electronics included with the T-Rex kits have also evolved alongside the mechanical characteristics of the model. The initial 400S (short can) and 400L motors have been replaced by increasingly powerful and more efficient motors including the 420L series (XL and early SE), the 430L series (SE models), and the 430 XL (SE V2)."

[Jonnyheli]

Originally Posted by CyprusDave

My understanding is that the original 450 size heli was called that because it used a Mabuchi 450 motor. Just for interest, the brushed motor in an E-Sky Lama coax is a 180 size, and the Big Lama is I think a 380. Another common size in early electric RC model (cars and boats) was the 540 size (hot stuff in it's day!)

Ahh yes! The 540 can motor. Tamiya still supply those with their kits. They do the job fine, however, as you say, most people will take that straight out and put in a brushless motor and ESC. And I lipo to go with it

I have the tunned 540 motor in my 1:10 touring car. It's fast, although the brushes need changing every now and then.

Jonny

[CyprusDave]

Originally Posted by redbird300

Interesting Dave. And look what I found here http://en.wikipedia.org/wiki/T-Rex_(RC_helicopter). As I said, I don't know the whole history, just trying to add some bits and pieces of information.

"The electronics included with the T-Rex kits have also evolved alongside the mechanical characteristics of the model. The initial 400S (short can) and 400L motors have been replaced by increasingly powerful and more efficient motors including the 420L series (XL and early SE), the 430L series (SE models), and the 430 XL (SE V2)."

Yeah, and also says that early ESCs were 25 and 35 amp, so can't have been a 450 watt motor

[dayshaddow]

intresting read chaps
what is a blade 400..ive heard it a 350 class...but the same people tell me an esky honey bee fp is a 300 class heli,not to sound like a broken record but the esky big lama is powered by two 380 fp bee motors and is the same lenghth as a bee but shorter blades,my aligh 250 uses 205 ml blades i think and my 450 is using esky belt cp 450 blades at 315 ml

cant we just use power to weight ratio as a heli class

[redbird300]

Originally Posted by CyprusDave

Yeah, and also says that early ESCs were 25 and 35 amp, so can't have been a 450 watt motor

I agree. Wonder what the real reason behind the "450" number would be ? Or is the Mabuchi 450 the same as that 400S and 400L motor ?

[CyprusDave]

Originally Posted by dayshaddow

cant we just use power to weight ratio as a heli class

Not really, as a stock Belt is the same size and weight as a T-Rex 450 or clone with a hot Scorpion motor, but the power to weight ratio of the Rex is over twice that of the Belt. So probably even more confusing

[Tomstoy2]

I prefer to think that all the manufacturers got together one night for a few shots, smoked some really good sh*t and came up with this mess, laughing their asses off the whole time. Kind of like how the place I work at makes business decisions, ( don't know what they are smoking, but I guarantee you're not going to find that in any dispencary anywhere ).

[CyprusDave]

Originally Posted by redbird300

I agree. Wonder what the real reason behind the "450" number would be ? Or is the Mabuchi 450 the same as that 400S and 400L motor ?

Looking a bit deeper, I can't seem to find a Mabuchi with an actual code of 450. I think Align just picked a number - maybe a Feng Shui or Chinese numerolgy thing

[redbird300]

Originally Posted by CyprusDave

Looking a bit deeper, I can't seem to find a Mabuchi with an actual code of 450. I think Align just picked a number - maybe a Feng Shui or Chinese numerolgy thing

Or they have really heavy sh*t down there.

[dayshaddow]

very good point there dave
so the align 100 or msr before i head off to do other things....someone was smoking the herb at align when they came up with the 100 shorly..at least eflight just called it an msr with no ranking apart from epicly good fun(not on the box i know) didnt study marketing sorry

[Tomstoy2]

I don't know, maybe if I smoked some of what ever Raf is into there I would?

Raf, buddy, you just ain't 'normal'. Between your builds, the threads, math computations, salinity figures, and what not has forced me to this conclusion.
Do you do taxes, too?

[redbird300]

Originally Posted by Tomstoy2

I don't know, maybe if I smoked some of what ever Raf is into there I would?

Raf, buddy, you just ain't 'normal'. Between your builds, the threads, math computations, salinity figures, and what not has forced me to this conclusion.
Do you do taxes, too?

Well, last time I did my own taxes, I got 2 years of confined isolation in the local jail, once the tax inspector understood how I tried to rob him.

Me crazy ? there....alone....for years...nobody around...insanity ?
NOOOOOOOOOO - HUHUHUHUHAHAHAHAHAHAAAAAAA !

Enough jokes now, gotta dissect the neighbours dog to find out what happened to that lipo.

[Singular9]

i have an excalibur XC9970 War Bird, not the war bird 2 (there is some confusion), what # is that 100, 250...?

[dayshaddow]

looks to be the same size as an msr so probily 100 class??? just looked up your heli on exrc and they say its an outdoor heli.nope its not perhaps on a windless day

[Singular9]

Could you explain your reasoning, and what is the difference between 100 and 250. Pictures and secs of some 250's match my Excalibur warbird.