Logo 600 on 6s why not?

[rcav8tor]

I run my Trex 600 on 6s and i like the logo 600 flybarless why won't it fly on 6s.
I'm new to helis why do i need to run 10s. because if i have to buy a new set of packs i guess i will
just make my Trex flybarless and fly that on 6s. like i said i new to the heli world

[Eyon]

6s on the logo works well...very very well! doesnt have the insane power, requires more pitch management, but if geared correct its still an awesome machine

[jamesotron99]

I run my Trex 600 on 6s and i like the logo 600 flybarless why won't it fly on 6s.
I'm new to helis why do i need to run 10s. because if i have to buy a new set of packs i guess i will
just make my Trex flybarless and fly that on 6s. like i said i new to the heli world

Of course you *can* fly a Logo 600 on a 6S pack, but would you buy a Ferrari and put a Skoda engine in it?

[Ticidytoc]

If you fly the 600E on 6s and are happy with the performance then you should be fine with the Mikado product on 6s. It's all about what you want from the machine and your ability as a pilot.

If your learning, doing basic hovering, some forward flight and smooth aerobatics the 6s IMO would be enough for you. We have seen the 6s setups can do 3D on the Trex, it may not be the most efficient setup, but it works none the less.

The Logos will not fly worse than your 600E on 6s, esp. if your going to run a flybarless setup. This should help you gain anywhere from :30-:45 more in flight time possibly even longer.

A 10s setup can give you a longer flight time, or more power, but the motor/battery setup would have to be configured this way. ie. people say the Raptor is too heavy, short flight times, etc... I configured a combo for one pilot who was learning to fly on his E620/550 that allowed him to train for 8-10 minutes. Yes it was no power house, but it got the job done, he is able to hover, do forward flight, and even flip and roll the machine. If he is ready for more power, then a simple motor and pinion swap is all thats needed. His flight time will obviously drop from 8-10 minutes and be somewhere more around 4-5.

We have a second pilot who is also learning, he is using 5s on a raptor, and is happy with the performance. when hes ready, he can join the 2 packs together, swap motor and go 10s.

So you see, 10s has its advantages, 6s works,and I see no reason to dump all of your 6s stuff and go 10s if the 6s is currently doing the job for you.

Of course you *can* fly a Logo 600 on a 6S pack, but would you buy a Ferrari and put a Skoda engine in it?

Would your folks buy you a Farrari for your first car? I think not.

You don't need a Ferrari to learn how to fly. I think what most people are missing is the fact not everyone is a 3d hard core pilot. Not everyone flies 3d, some fly heli's around doing smooth aerobatics. So a Honda with properly tuned suspension would be enough to win the race, as the inexperienced driver in the Ferrari would spin out in turn 2 and come in last.:wink:

Matt

[Eyon]

just to let you all know, a certain very well known mikado pilot has just set up a 6s machine:noteworthy

[MrMel]

Have a look at this T-rex on 6s, with the new 30C batteries and new german motor, you can really have good performance :) Not the flighttime though.

http://www.junkshop.nu/flyg/paldalen_20071020/paldalen_trex600_big.wmv

[rcav8tor]

Thanks for the input
also i was thinking of a NUE 1515 2Y @ 1100kv for a motor on 6s. I understand that the Mikado is around a 12 to 1 gear ratio. where my Trex is 17 to 1. is the logo 600 12 to 1

Thanks again

[Ticidytoc]

The Neu 15xx will not be happy on 6s. 24,000 on the rotor for those motors is not enough, they wake up around 35,000 - 40,000. If you are going with the Neu the 1910-1Y-H would be a better choice IMO. They are happy around the 25,000 - 30,000. Or one of the outrunner motors like the Z-Power in the 1050-1100kv rage would suit you better.

[th3tick]

The Neu 15xx will not be happy on 6s. 24,000 on the rotor for those motors is not enough, they wake up around 35,000 - 40,000. If you are going with the Neu the 1910-1Y-H would be a better choice IMO. They are happy around the 25,000 - 30,000. Or one of the outrunner motors like the Z-Power in the 1050-1100kv rage would suit you better.

I've got a 1910 on my Logo 500 running 6S. To get my target ~2200 headspeed, I need to run the 16 or 17 tooth pinion (Mod 0.7). For those, that comes out the motor running around 19,800 or 21,000 RPM.

To get 25,000-30,000, I'd have to run a 12T or 13T pinion, which leads to a headspeed calculation of 1645 or 1743, which is way too low, and then wouldn't result in the range you're specifying.

That all said, it seems to be working quite well for me, but I don't see how to get the RPM range you're specifying with this motor on 6S on a Logo 500/600.

I have been thinking on whether I should go to the 16T instead of the 17T since I have to govern it down to 65% to achieve the 2200, however...

John

[Ticidytoc]

On a 6s pack the motor will turn around 23,000 at 100%. According to Steve the ORK's are happiest around 25+. Not saying that the ORK will not work below 25K but they do come alive when spun closer to 30K. The "H" series do not seem to have a problem with the 30K's but I found the older ORK's started to get hot swinging 600's for hard 3D. 550's were no problem for them on the 600E.

Using a 13T/153T on 6s should give you 1800 on the head. If you go to a 14T then thats in the 2000's. More than enough for learning IMO. Of course if you want to spin 2200 then you will need a larger pinion.

Changing pinion size does NOT increase can rotor RPM, voltage/kv does, i.e. more cells or a higher kv on the motor. You either need an ORK in the 1200kv range or go to 7 cells to get the can rotor RPM's up.

i.e. 7s on the 1910/1y would put it in the 27,000 RPM range. or.....
6s on a 1250kv motor would net you 27,000 RPM.

The 15xx would be a poor choice since the can design likes the higher rpm and you will be well below the "happy" zone for that motor at 24K when it likes to be in 40K. If your going to buy a Neu, then the 1910/1Y is a better choice IMO.

From my initial observations, you would need a 1250kv motor on a 13T/153T to get you closer to that 2200 HS.

-Matt

[th3tick]

OK, I see exactly what you're saying now. Thanks.

I now think even more so I should go to a different pinion and not run it slower. It appears a 15T should get me in the 23,000 range for 2200 headspeed, but most of the calculators have some sort of an efficiency calculation included as well. At 90%, that comes out to the 16T being the right match.

Does anyone have a ballpark for how efficient the gearing on the Logo 500/600 is?

John

[Ticidytoc]

John I think you are missing one thing. Changing pinion does not change motor RPM. Changing pinion changes gear ratio which in turn changes main rotor RPM.

This gets a little more in depth, but for simplicities sake if you have a 1050kv motor and apply 1V to it it will spin at 1050 RPM, if you apply 22.2V (6s pack) it will spin at 23,310 RPM. (V x Kv = motor RPM at 100% throttle)

Your motor RPM will be limited by (voltage x Kv).

So you see, the motor RPM stays (somewhat) constant, and gear ratio changes to increase HS with an increase in tooth count on your pinion.

-Matt

[Mercuriell]

Can someone explain to me why with these brushless motors, which depend on frequencies generated from 3 phase ESC, that voltage makes such a difference to rpm, I thought the speed would be proportional to frequency and power to current.

[Ticidytoc]

Sheesh John, I was trying to keep things simple here. Why don't you do some research and get back to us on that. That way we will know what the hall sensors are for. ;)

[BruceW]

The sweet spot on the motor speed goes back to the number of poles, windings on each stator and electrical resistance. Motor can diameter probably plays in to this also.

http://en.wikipedia.org/wiki/Brushless_DC_electric_motor

[th3tick]

John I think you are missing one thing. Changing pinion does not change motor RPM. Changing pinion changes gear ratio which in turn changes main rotor RPM.

This gets a little more in depth, but for simplicities sake if you have a 1050kv motor and apply 1V to it it will spin at 1050 RPM, if you apply 22.2V (6s pack) it will spin at 23,310 RPM. (V x Kv = motor RPM at 100% throttle)

Your motor RPM will be limited by (voltage x Kv).

So you see, the motor RPM stays (somewhat) constant, and gear ratio changes to increase HS with an increase in tooth count on your pinion.

-Matt

Actually, I think I've got it now. The issue I'm trying to resolve is that I'm having to govern my motor speed down to accommodate the headspeed I want more than I think I should be. I'm running at 65% on the 17T pinion to achieve 2250, when I'd likely be better off using a higher percentage and the 16T pinion. My main point (now) is trying to keep the motor speed up when trying to achieve that headspeed, thus a pinion change is in order.

Changing the ESC %age does change the motor speed. Heck, I wonder if I should be doing 15T and higher %, but I'll wait to see how the 16T works out %-wise.

But thanks nonetheless. The more I learn, the more I know I don't yet know.

Sadly, I've now got serious battery issues to address before I'll be flying again. My TP210V apparently has been busted, and thus resulting in puffed packs... :bawl

John

[OICU812]

I ran that exact motor John, the 16tooth is the sweetspot. run it 83% in idle 2 and you will be golden.