Atom technical stuff

[BBRFST]

I was wanting to run gov. mode on my Atom 500 with the 60amp Pentium Hobbywing esc, but I'm not sure if I run "low" or "High" mode.
The directions show a formula for headspeed but it doesn't work out? I have the stock motor, 10 tooth pinion, and 6s 3000 pack. Can anybody help me on headspeed formula or recommend which setting to use?

Thanks

[skunkworx]

Sean, because it's a low Kv motor, you can go to high timing and it should work fine. As to the headspeeds, all you would need to do is get the gear ratios and then do the math based off your expected motor rpm's.

For instance, the Atom runs a 7.8:1 on the 10t pinion. Now your motor running on say 25V would be at 1080Kv X 25V = 27,000rpm's.
Take the motor speed, divide it by the gear ratio 27K / 7.8:1 = 3461rpm's

Realistically though, your voltage would be at like 23V under load (or less), so headspeeds would most likely be around 3184rpm's max. I'm not 100% certain I have all the numbers correct, but they at least give you an idea how they come up with figures. No matter the exact figure, that headspeed would be ripping on the Atom no doubt! I can't wait to use the 10t pinion on mine.

Info source: http://www.compassmodel.com/atom500e.php

[BBRFST]

Originally Posted by skunkworx

Sean, because it's a low Kv motor, you can go to high timing and it should work fine. As to the headspeeds, all you would need to do is get the gear ratios and then do the math based off your expected motor rpm's.

For instance, the Atom runs a 7.8:1 on the 10t pinion. Now your motor running on say 25V would be at 1080Kv X 25V = 27,000rpm's.
Take the motor speed, divide it by the gear ratio 27K / 7.8:1 = 3461rpm's

Realistically though, your voltage would be at like 23V under load (or less), so headspeeds would most likely be around 3184rpm's max. I'm not 100% certain I have all the numbers correct, but they at least give you an idea how they come up with figures. No matter the exact figure, that headspeed would be ripping on the Atom no doubt! I can't wait to use the 10t pinion on mine.

Info source: http://www.compassmodel.com/atom500e.php

Your numbers are right on, using the iphone head speed app. on my buddy's phone we got HS of 3188rpm @ 100% throttle on a fully charged 3000 pack. I'm now using the gov. and have the HS set to 2990rpm. I'm still playing around with it thou I want find a good HS so I can run my batteries cooler. Motor is cool, ESC is cool , and batteries are just warm after 5:30 flight time.

Thanks Tim

[skunkworx]

Cool beans! Glad to know I'm not a complete idiot.

[Cullen Colapietro]

anyone using this on their 500?

http://www.maxprotechnic.com/MaxproE....php?page=UBEC

[BBRFST]

Originally Posted by simonseize

anyone using this on their 500?

http://www.maxprotechnic.com/MaxproE....php?page=UBEC

I would go with the CC BEC, a lot of people are using it and I haven't heard any complaints yet. Will this BEC handle your load? have you put an amp meter in line with your setup to see what kind of current your drawing? The CC Bec can handle more current from what I've read. Is there a reason you don't want to use the CC BEC?

[Jimmy!]

In my opinion, an external BEC is not necessary on the Atom. The stock ESC's and most decent ESC's, like Kontronik, Align, and Castle output plenty. The only time I might consider an external circuit would be if I went flybarless and knew the servos would be stressed more -OR- if I started having issues after stretching to 515's. Even then, Kontronik, Castle and likely the Platinum/Pro HW could probably handle it all well.

Take it with some salt, but think about how well most systems work w/o external power on 500's.

[BBRFST]

Originally Posted by audiracerj

In my opinion, an external BEC is not necessary on the Atom. The stock ESC's and most decent ESC's, like Kontronik, Align, and Castle output plenty. The only time I might consider an external circuit would be if I went flybarless and knew the servos would be stressed more -OR- if I started having issues after stretching to 515's. Even then, Kontronik, Castle and likely the Platinum/Pro HW could probably handle it all well.

Take it with some salt, but think about how well most systems work w/o external power on 500's.

I agree, my mistake I thought we were in the 6HV thread

[Cullen Colapietro]

I bought the heli used and thought, since it was there, that I'd use it. The guy had it wired to an external Rx battery. I got rid of that, especially since it looks like it was almost punctured in a crash or something AND it weighed over 100g.

I used the Align w/o issue in my T-rex 500, this has a 100A Align, so I could run it w/o the UBEC, just thought, since it's there...

[Cullen Colapietro]

Soo,

I've been trying to get my new Atom 500 up and flying. A simple task you say? Well, I agree, however, I've got something super funky going on.

When I first built up the heli, I took it to a fun fly. I lifted off and the thing was unflyable. The head was moving all over the place, like a bobber on the water. I figured, OK, these analog servos wont cut it.

I bought digitals and changed the no name BEC to a CC BEC 10 Amp.

The only other notable difference between this heli and others was the Align 100 Amp ESC w/ no BEC from a t-rex 600 E kit.

I went to fly today w/ the new servos and expected a perfect flight. Much to my dismay, the heli had the same bobber issue except it was WAY worse. I thought I wasn't going to bring it back down. I'd correct one way and the heli would re-correct in the other direction.

So I thought, what the h%ll!

The only thing I can think is the stock dampeners weren't doing their job. When I checked post "flight", I thought it strange I could rock the blades inside the grips.

I went home and built up some KBDD dampeners using t-rex 500 dampeners ground down to fit and cut off the little protruding ring on them. I stacked 2 in each grip and things look O.K., but just O.K. The dampeners are pushing slightly up against the bearings and the feel slightly tight, but I figure they'll still fly.

So, what are your thoughts? Will this work or am I setting myself up for disaster?

[TheBum]

Did you make sure you resized the links in the head to be loose enough? The only time I ever fought with my Atom was when the linkages stiffened up on me one day. You should be able to slap a paddle and have the flybar swing up and down at least 3 or 4 times.

Make sure that the phasing pin is in the slot on the washout block; if the swash gets pushed down all the way while power is off, the pin may slip out of the slot.

I've also had an occasional issue where the main blade grip gets rotated such that the upper mixer arm gets thrown out of joint. It's doubtful that you're having this problem because the heli will practically shake itself apart. Been there, done that.

Are you using any shims on the blades? I found that I had to use two 0.5mm shims to get the blades to fit right and not put too much stress on the grips.

[Cullen Colapietro]

The blades came with washers. They fit tight, but nothing crazy.

I'll check my links again, but I did size them all, so possibly not.

The dampeners just seemed to give WAY too much ( I can only compare to my T500).

Thanks for the suggestions, I'll try the links again.

Cullen

Any thoughts on the dampeners being to tight since I basically made them myself?

[Ah Clem]

I sized the links on mine three time before I got it where I wanted it.

[Jimmy!]

I think you need to check each link on the specific ball on which it goes. I used the same ball to test and size all my links, but when I installed them, I realised that the balls have variances in size, causing some links to still be tight. So when you go through, check all the links to make sure they're actually good.

[Dflyer]

Good tip Jimmy, i always do it like you explained !

Grtz,
Dirk

[skunkworx]

The stock dampener needs a bit more headspeed too. If you are running the 8t pinion, chances are you'll see a bit of bobbling (especially at low head speeds). Even on a 9t, you have to run a minimum curve of like 60%-70%. I personally am not much of a fan of the Delrin dampeners anymore. While they do give you a nice rigid head for 3D, they seem to wear down quickly and don't give very consistent dampening like I'm used to on any other heli.

I tried the KBDD dampeners on my Knight with somewhat limited success. They're the Trex 600 ones with some stock T600 rubber rings to take up the extra space. Seeing all the dampeners I have for my Knight are the 6mm, they're not doing me any good on the 8mm spindle. If I could get some material like the Trueblood dampeners on my old 450, I think I would be set for life. I never had much of a problem with those ones and the dampening was perfect no matter the orientation or how hard/soft you were flying.

[Jimmy!]

Here is some very good info on setting up the head block for most any heli, thanks to Ah Clem.


This is extremely easy to do (if you started flying helicopters back in the dark ages when you had to set the coning angle-I still had my coning angle tool).

I had to epoxy the headblock on my Mini-Titan and EXI 450 Pro Clone due to the holes wearing egg-shaped.

1) Remove the head block (leaving the blades/linkage installed)

2) Clean the hole in the head and the main rotor shaft (the portion which is inserted into the head block).

3) Put a thin layer of JB weld inside the hole in the headblock, then a thin layer on the outside of the main rotor shaft.

4) Re-install the main rotor head with the bolt and all connect the linkage.

5) Set the pitch to zero degrees

6) Measure the vertical distance from the tail boom to the blade tip on one blade, then rotate the head and measure the distance from the second blade tip to the tail boom (this is where the coning angle tool comes in handy).

7 ) Rock the head block slightly as necessary and rotate the head as necessary to get the distance from both blade tips to the boom equal before the epoxy sets.

It took me longer to type this than it did to actually do it, last time.

Again, my Atom never wore out in this area. The Mini-Titan got pretty bad, but never had a boom strike from this issue. The Mini had gross tracking issues before I figured out that this was the problem.

[Cullen Colapietro]

To swash or not to swash (expo that is)

[BBRFST]

Hi guys does any one know who make the main blades for the Atom, I wanted to get a replacement set. I do love the Rotor-Tech 425's but I would prefer to use the stock blades if I crash again.

[TheBum]

Try the Mavrikk G5 Pro blades. That's all I fly now on my Atom 500 and they're relatively inexpensive.