Axe CP separations and setup journal

[Edwinssiv]

Ray, I have been exploring different ways to reduce the weight of my Axe...
Most go to reducing electronic parts...I can move to a lighter ESC and remove about 10g-12g...with the motor I can go to the Eflite 400 and that is 12g and with the splicing of the wires/connectors I could squeeze another 10g I am guessing...I am still flying with the Bell-Hiller weights on the head, I can remove those. That would be a few grams...if I went back to the palstic head parts instead of CNC, but I fear that the head speed I would be generating they might not hold up with it...it is an interesting concept...I wonder if I went to an outrunner I could shave some...but the battery location is not good for that...hmmmmmmm :thinking
even if we can shave off 10% what would that equate in terms of flight time? in stability?

Ed

[Ray K.]

Ed-

I guess I'm not so sure what it would do to flight duration or stability. It's reasonable to think that flight times will slightly improve, and that stability will slightly suffer. The real pay-off is going to be in flight performance, though. Poppier collective, and sharper cyclic too.

I'm also a car guy, and when I was building my last project car, I did a weight reduction project on it. The results that I got from removing just 150 lbs from a 2400-lb car were pretty significant. I lost 2/10's in the quarter-mile, and my cornering and braking performance were also enhanced. Basically, reducing weight allows an object in motion to accelerate (that includes deceleration also, because technically that *is* acceleration) more quickly. For a helicopter, that means that all aspects of performance will be enhanced- except yaw, which would require a reduced polar moment of inertia. But like I said, benefit will certainly be felt in collective and cyclic motion.

So if I was able to reduce my car's weight by 6.25% and it made a big difference, a 10% reduction in weight on a helicopter should be pretty significant. That's why I'm so Hell-bent on saving even just 30 or 40 grams!

-Ray

[markind]

I am so jealous Mark...I have been heli-less for a couple of days now. I have been meaning to work on the Axe but have not had the time or energy...and stuck at work on a very beautiful Saturday morning is really depressing.:thumbdown:
So when I get home this afternoon I intend on getting the Axe flying again as I will have to wait a couple of days for parts on the BH.

You'd be green if you saw me yesterday - perfect, warm, sunny, and fairly calm in the morning with a clean wind peaking at maybe 10 kn by afternoon.

I had the whole field to myself and got in 6 awesome flights with my 'rex (and 2 on my Twister) which made it a great morning. My 8's are big and looking good now and I got in a lot of slow nose-in approaches.

In the evening I got bench time with my Axe and Belt Mod. I assembled the custom tail case and strung the belt easily, and put locktite where needed. Still needs a servo and something to guide the control rod (the stock TREX 450 control rod guides are too big - not sure why Don included them). I did not realize the kit comes with a CF tail boom so I did not need my Walmart knitting needles (but I cut them and they are PERFECT!!) so I have a couple spares ready to go (hopefully won't need them!!).

I then worked on the top of the rotor head. I had to dispose of all my Purple anodized CnC bits from Tower. They suck. I re-installed the stock Main Shaft and plastic Center Hub and Slider, and then installed the Microheli bits for the Flybar Control System, and then installed the Bell-Hiller kit from Tower, and finally I installed the Microheli Swashplate.

I lubed the whole thing with silicon lube spray but the flybar is still too stiff. I think a lot of friction is coming from the O-ring dampeners, and at least one of the bearings from the Tower Bell Hiller kit is crap. I tried to tap one out but they are in there good and I did not want to damage anything.

Tonight I will dis-assemble the Bell-Hiller kit again and re-do the Feathering Shaft install - something about the o-rings is binding on me... :confused: There are supposed to be two on each side but... ???

[Edwinssiv]

Well...Saturday got windy by the time I finished work so I was happy that I was not missing tooooo much...Sunday morning was very nice as well...so again I was sad and depressed...lol.
Hoping to get my Black Hawk parts in today or tomorrow so I will be up and running with both helis no later than this weekend.
I have my Axe apart Mark, so I will check on the o-rings tonight when I get home.
I went and bought a smaller 25A ESC for the Eflite 400 motor...the 35A was causing the motor to heat up alot...
I do know that I did not have any binding on the install of the Bell-Hiller but I did have some with the Micro Heli parts...some 1000 grit wet dry sand paper and the problem was solved.

[Ray K.]

I'm glad that you guys have had good chances to fly.... I'm on my twenty-something-th consecutive day at work, and my next day off is May 11th. I have another 19-day straight run after that, and then my Summer should be back down to *only* 6-day weeks.... Slave to the Grind!

All these hours are great and everything, but my time to fly is pretty much on a moratorium until June or so. Sucks. I'm pretty much relegated to the simulator only. It kills me knowing that Axe is all checked out and ready to rock, and that the 'Rex will only need some tracking adjustments and it'll be ready. I'm biding my time as best I can, but it's getting pretty tough... especially considering that my AMA card should be here any day now.

Enough *****ing... onto the goodies!

I was playing around on the sim last night with the ACP, and found some interesting things. First, I tried giving the ACP longer blades, and that was a disaster. I went into it thinking that it was possible that there simply wasn't enough lift to be made from the stock blades regardless of how much power was being put to them. Boy, was I wrong! Turns out that power is the key. Longer blades did indeed help collective performance, but they also killed cyclic performance. So I swapped back to the stock blades, and put an abusively powerful motor in. Totally woke the heli up! Based on my playing around, it looks like anything in the 230+ Watt range is where it's at.... and that means that a Park 400, a Himax 2025, or another motor of that ilk would be best- especially for you guys that are running belt tails. Of course weight still plays a role, but it seems like at least on the sim, weight becomes a little less of an issue when you've got mongo power. I also messed around with the headspeed a little, and discovered that anything beyond about 3200 RPM is a waste of time and effort. Looks like 2800-3000 is ideal. For the collective pitch range, +/- 10° or 11° is more than adequate. 12° (like my FA-Sr. is set up for) actually makes the heli pitch up pretty bad during fast forward flight unless you have absolutely PERFECT collective management- it's pretty unforgiving. I'll be changing my setup after this discovery.

I'm still sitting on the fence as to whether or not I'm going to re-invent the ACP or not. It's certainly become my little pet project, and I'd love to extract serious performance out of it. On the other hand, and like I've said before, I'm pretty much sick of dumping cash into it. So maybe you guys can help me to make that decision-

What does your Axe weigh (with the belt mod), and what is the rest of your setup? From the simulator, it would appear that an ACP that weighs any more than 550g is going to have crappy performance, regardless of the mods that are on-board. So if I can come up with a recipe for the "ultimate" ACP without spending more than $350 to do it, I'm there.....

Time for a new chapter in the perfect Axe CP.... maybe.

-Ray

[Edwinssiv]

I have put the Axe on hold for now because the parts came in for my Black Hawk...but I am going to the Park 400 with the 15 tooth pinion...that should put my head speed at around 2997 calculated...but that will come to be a little later....I ended up with the Eflite 25A ESC (because that was all the LHS that was open on Sunday had) so only gained 1 gram off the weight but the motor drops me 12 grams so that should put me around 472 grams or so which is closer to the stated weight of a the flyable Axe from their manual of 468 grams...I should have this complete before the weekend and I will keep you informed.
There is another thread on RC Groups that some one has converted an Axe to a brushless motor tail with pitch control....less expensive than the belt mod and looks like it is pretty solid. I am just not to keen on the looks of the bracket they built for it...They don't state what the weight is but they did have to put a 20 gram lead weight in the nose o balance it...lol...so the weight has to be up there!

[Edwinssiv]

You know Ray...that is a terrible schedule...geez man...I remember when I worked like that...but no more...I could not handle that kind of schedule any more...getting too old or spoiled....maybe both...lol :YeaBaby:

[Ray K.]

A BL TM with adjustable pitch.... hmmmm....

It's an interesting concept, and not without it's merits, but the first thing that goes through my head when I think about that is HEAVY... and not very graceful, either. You're still going to need a separate ESC for the TM, and I'm not exactly sure how one would control it... maybe an extra channel with throttle-to-aux mixing that runs up the motor as soon as you have any throttle input. Like I said, not very graceful, and that's not how I like to do things. Cool idea, though! Innovative.

I just weighed my Axe again, and I came up with 484g. Thought I was at least a little lighter that that... Oh well. After doing some research online, I found that I can save about 10g on my batteries if I get new ones. I can also save another 16g if I swap my GY240 out for an EFlite G90. A Park 400 is going to add 20g to my setup, so I'll be down only 6 grams. I don't think that a new ESC is going to have much weight difference, but I think that 5g is a safe guess. Down only 1 gram now.... It's really hard to say how much weight the tail mod is going to add... I'm afraid to even guess. I'll be losing the TM, the TM ESC, both of the sets of Dean's Micro connectors that go with the system, and the wire that runs down the boom to the TM. I'll be adding another servo, a belt, a variable pitch tail system, the roller block, and the main belt drive gear. For all I know, it could just about be a wash between the two setups. Add on the B/H head, and I'm likely to be right back where I started in terms of weight. Except I spent $500 to get there.... bummer. I'll have A LOT more power, though, and proper tail and cyclic control to go with it. This is looking like not the most prudent idea.... I'm still entertaining thoughts of doing it anyway, though. It's only money... I'll make more.

BTW, I erroneously stated in my last post that 230 Watts would be good for an ACP... I had a serious brainfart there. 230 would be like putting a supercharged Ford 302 in a Geo Metro! Can we say "overkill"? 190 or so Watts is more accurate.

If I can do all this crap and still find a way to eliminate another 20 or 30 grams from the FrankenAxe, I'll be happy. It would make for one badass little helicopter! Hard 3D will probably still be out of the question, but at least *some* 3D should be possible. Even an ACP that can do a fast tail-slide without blowing out the tail and then pulling out into fast backwards inverted flight without biffing would be pretty impressive! It would certainly be fun... So I guess the question now is how badly do I want a really kick-ass novelty helicopter?

Work....

Yeah, all these hours are starting to take a toll on me, but this is also a new job, and I'm kind of paying my dues right now. I came to this place with more experience than a lot of the guys that work there, and I'm currently under consideration for being my department's supervisor. They've made no secret about that, so anything I can do for now that will demonstrate my commitment is a good thing. Reviews are at the end of May... we'll see if all my hard work gets me anywhere!

-Ray

[Edwinssiv]

Morning Ray,
This is what princew wrote on RC Groups...
"Well actually the motor response time is pretty irrelevant with this setup. As long as the blades are spinning at a resonable rpm the gyro and tail servo do all the work. We tried everything under the sun to get a bl motor to work well with the stock fixed pitch blades, and finally I said screw it lets put a trex tail on this thing.

We hooked both the main speed controller and the tail speed controller to the throttle channel so they have a linear relationship to throttle input vs rpm (same as a belt drive would do) The tail motor keeps up nicely with the main and always has a locked on tail. Basically this setup has all the benefits of a belt driven tail without installing a belt, and the whole tail conversion (not including the bl conversion we did or the servo/gyro) only cost around $30-$40 in new parts."
So I think what they did was run a Y harness...not sure. But, I did see this mod done by some one else and they just had the tail motor on a Y harness to the same ESC so the tail would spin up at the same time as the main...as long as you have rpms on the tail motor the variable pitch can do the rest...no waiting on the tail motor to speed up or reverse direction...but ultimately it equates to more weight
On a side note...there is interesting agruement starting...a guy saying that the Axe handles winds better than his Trex because of the low head speed...lol...says he can fly in 10mph winds no problem...I never had that kind of luck...I feel I am at the intermediate stage of learning to fly and the Axe has restricted me in being able to continue to learn more because of it's limitations...but it is fun to tinker with now...

Been considering your testing on the sim...so what I was thinking was this. As long as the weight is close to the original flying weight of the Axe, if you get the head speed up you will have faster cyclic control...with the Bell-Hiller upgrade that will be very quick and very touchy...the reduction in weight is limiting because there is only so much you can do, the Axe is a pretty light heli to start with...but as you said the blades limit you...there is just not enough surface to allow hard core 3D. Getting the head speed up around the 3000rpm mark will give more authority and allow you to perform at least flips, rolls and some mild backwards flight with confidence...but this is considering I have the belt driven tail which should hold better than the motor driven tail and hopefully not blow out...Learning backwards flight with having to hold the tail on the stock Axe I think would be very stressfull :shock:

As to work...
Good luck on the review and I hope you get the promotion! That would be great! I hope you can find some spare minutes to get out and smell the roses so you don't burn out! Glad to hear that they are taking notice of your hard work and dedication...to many companies and managers don't even look anymore.

Ed

[markind]

I got my frame modified last night, and did not have to split the left from the right like I thought. Just removed one servo, the Dremel does the rest. - just don't knick any wires! :D

I also assembled the pulley thingy and tinkered with the belt and gears - its tricky to get everything in with the right order - but I'll fumble-thumb my way through it somehow... :confused:

[Edwinssiv]

Mark...if you need any help let me know...
I finished repairng the Black Hawk this morning...I would have been done sooner but I had one link out of line just a little(everything was level and worked...but I wanted it to be lined up correctly) ...so I tore the thing down again, made it all nice and lined up...then put it back together. Test hovered this morning in the rec room and it flew great! So...now back to the Axe this evening and get it up and flying.

Ed

[markind]

Ok, I need a tip in the right direction here with this Belt Mod.

I got everything all assembled and even got to going over radio settings and making sure all the servos are contered. Check and the Gy240 is working. All good, but then...

Every time she spins up just a little bit, the belt slips off. It just pops up and over the gear.

It makes me want to install that gear upside down from what the picture in the instructions say. That flange looks like it would keep the belt on.

Or is there another trick?

Link to instructions:

http://tinyurl.com/3rj8up

I'm looking at page 5. Is that gear upside down? :confused:

[Ray K.]

My mind is made.

...and it's not what you think.

After examining the possibility of re-inventing the ACP into a real monster over and over again, I've decided NOT to do it. You see, $500 is a lot of cheese, no matter how you look at it. So instead of dumping all this money into a bird that I already have and rarely fly anymore, I'm going to get a new machine.

Instead of spending all that loot on getting all crazy over 3 or 4 grams and buying more stuff to replace stuff that I already have, I'm going to step up into the nitro .50 game. Turns out that 500 bones will get me pretty far into my next fantasy project- an Audacity Pantera 50 with all the high-end goodies. One might argue that the $1800 or so I'm going to spend on the new bird far exceeds what it will take to re-do the Axe, but we're also talking about a whole new realm of rotary flight here- so let's keep apples with apples.

Like some of us mentioned recently, my little Axe will always hold a special place in my hangar... it's what got me addicted to helis, and it also showed me that I shouldn't be afraid to tinker and play around with things. The fact remains, though, that it will always be just an Axe, no matter what I do to it.

I took a long, hard look at what I'm doing now and where I want to be. I also took into consideration the weather (read: day-to-day flying conditions) here in Michigan, and the answer that I kept coming up with is that a .50 is the next logical step. I'm ready for big-boy performance, and that means getting into a big-boy helicopter.

I don't want this thread to stop, though- I started it so that it would become a think-tank and Brain Trust on what can be done with HeliMax's little wonder. I intend on remaining active with this thread to share ideas and answer questions, but I probably won't have any new material to contribute.

So- Mark and Ed, the torch has been passed on. Keep it going!

-Ray

[Edwinssiv]

Mark- No, I have the gears set up just in the instructions and I have no problems. First look at the idler block...check the guides...they probably are causing the belt to ride up as you spool up. You can pull them down gently and they will pop a little into a lower psotion...I did this on mine, make sure you are not rubbing the main gear!...you will have like a 1/16th of a gap from the top of the idler guide and the block...pull your blades and spin it up to see what is happening. I don't think you want to flip the gear and have it rub the top, as this will cause pre-mature wear on your belt. Check the alignment of everything first...you should be abel to diagnose what is going on. Take some pics from the sides and I might be able to help some.

Ray- I completely understand your thought and you best not go away!!!!!!!! I to, am not willing to put any more $$$$ into the Axe, only parts (maybe) from now on...it is a fun little bird when it is flying right...but it has built-in inherent limitations. Although I have no desire to get into nitro helis at this time....I would like to get a bigger heli at some point....Probably a 500 and maybe a 600...something that I can still fly around the parks and not have to worry about noise. We have a flying feild about 25 minutes from where I live but I don't want to have to take my heli all the way out there just to fly...All that will wait until I get better at flying. I was hoping my wife would have gotten into RC helis some more than she has. She was excited at first...but her interests are else where...she has had sucess with the Blade CX2 and that has made her happy...so I have no flying partner at this time...except you guys and some BH guys on RCU. :noteworthy.

With the stability, ease of flying, easy to work on and resonable costs I have had with the Black Hawk...any money for upgrades is going into this. Plus, I am considering another one of these so I will have 2 helis to fly at the park...no waiting for cool down...just switch helis and go...but I have been drooling over the Gazaur helis as well....may have to build one of them...I like the looks and they are different from the Trex which everyone flys. :D

[Edwinssiv]

Mark-Any progress? You have me waiting on edge!!!!
I have the Axe back up and running...Put the Eflite 400 3700kv with 12 tooth pinion in for right now...I have a head speed of 2464rpm calculated...a little slow but enough for me to fly it around some and still have pretty crisp controls. I will probably up the pinion to a 14 tooth later this week. I have not flown this thing in a while, I forgot how twitchy it is...
I received my free 6100 rx from Horizon Hobby yesterday...so it must mean I need another heli to put it in! :shock: I wonder how the wife will take that one? ROFL
I am in trouble for sure!

[Edwinssiv]

Where is everyone? Must be out flying :YeaBaby:
This morning I put the 14 tooth pinion on the Eflite 400 3700kv.
All I will say is :wow2:
That moved the head speed up to 3875 calculated. The Axe jumps and has more power than I imagined! Very,very quick...I had to be careful in the rec room because I would barely up the throttle and the thing would jump something fierce!
When I was running the Eflite 6 Series 2200 with the 24 tooth pinion it did not respond the way it does now...The 400 has alot more torque than the 6 series.
So the Axe is now a little beast! I still want to add some tail supports so it does not flex but for now the Axe is finished...I will keep flying it because it definately keeps me on my toes and should hone my skills!

[markind]

Been swamped at work last couple days, no bench time yet. Today I get to out 'Rex'n. :D

Next step is to tug on those pulleys to see if they indeed snap into a lower position.

Right now, the main gear's top edge is just barely in line with the top edge of the motor pinion. If neccessary, I can shave down the shaft bushing and lower the main gear a few mils if I have to, but to get it higher I would have to tug the pinion up off the motor shaft just slightly, and add a very fine spacer to the shaft bearing (somehow, not sure) so basically the main gear is fixed.

Once I get the next step figured out I'll post pics showing how things line up. I also need those screws to secure the tail boom - I'll check Radio Shack today...

[markind]

I had to scrap the Tower Bell-Hiller kit. Quality sucks. At least one bearing inside the blade grip was totally bad. I tried to tap it out, but they used a super-cement and those little craps are in there but good - and I ended up destroying it. Suck. :BSS

I am continuing on with the stock plastic blade grips and center hub. Still using the Microheli flybar control and swash. Just got to find some parts to finish it up...

YES I adjusted the belt pulleys and now I can get full throttle and the belt stays on! Cool. Had to reverse the Rudder channel and Gyro direction. The tail feels VERY SOLID. Getting close now...

It became a bit too windy to fly today... so I got more bench time in...

[markind]

Well, she's almost ready for sliding and hopping tests with training gear indoors in the big clubhouse with linoleum floor. :woohoo

But I think one of my HS-55s has gone south - it twitches a lot now. I see no explanation... Probably, I'll hafta replace it. Suck. :thumbdown:

I re-did the sub-trims and made sure that when radio is at Zero, the servos are level, and the blade pitch is zero degrees. I think I got the tracking pretty close too... We'll see...

The flybar swings ok. Maybe not perfectly loose-swinging like on my 'Rex... It will hafta do I guess...

I'm playing with the Pitch and Throttle Curves now. Trying to get 'er to feel like a good hover in my hand. Can't do that with my 'Rex - the tail is strong enough to twist 'er out of my hand and main rotor could split my skull and that would be a no-no. :hammer

I anticipate not a good response on the cyclic. But, one hurdle at a time...

[Edwinssiv]

Mark...sorry to hear about the bad bearing on your bell-hiller...I have had no problems with mine at all...
Glad you got the tail working well! It is a totally different heli with it. I putzed around today and did not go fly, even though it was perfect for it. Hopefully it stays nice and I can go at lunch and after work tomorrow. I did get out Saturday morning and flew some...the parks near the house had people so I went out in an open part of the desert near me...I was flying around and then all of the sudden I had trucks and cars coming from all over driving past me...so I only got one pack in for each heli before I said enough and packed it up.

[markind]

Mark...sorry to hear about the bad bearing on your bell-hiller...

Thanks for the sympathy - I also had to replace an HS-55. I can't believe it - it just decided to get twitchy. The gears were fine. I took it out to test it and it fails. I replaced it with a new one and the new one works perfectly from the same connection. Aaaachhh another 14 bux... :arggg:

She's ready for sliding and hopping tests again! Just need a little wires dressing. Perhaps tomorrow night in the clubhouse... :dontknow

Stats:

Less than 90 Watts at approximate hover

Canopy: 17.1g

Training Gear 13.4g

TP1320 pack: 88.2g

AUW: Dang my scale only goes to 7oz max... :tongue

[Ray K.]

...and such is life with model helicopters. It's strange that a HiTec servo should fail for no apparent reason- quality and longevity is what they're known for. On the other hand, servos are known to do that, though. At least it's only a $15 HS55 and not a $200 full-size digital wizz-bang servo.

The weather here was PERFECT today, and did I get to fly? OF COURSE NOT! I had to be at work at 0730, which is bad enough when I left work at 2330 the previous evening. On top of that, my girlfriend's mom passed away last night. I didn't get a wink of sleep, but not being able to fly is a small price to pay for being there for her and her family. It's been a rough few days, but at least it's over now, and she's not suffering any more- that's all I can ask for. She was like a mom to me too, and she will be dearly missed. Cancer's a *****.

The upside of this whole deal is that I may have recruited a new person into the hobby. My gf's dad, Mitchell, was a helicopter mechanic in Vietnam, and has shown interest in this hobby since I got into it. Since he's going to have some extra time on his hands and could use the companionship, I intend on taking him flying with me next time I go to the field. I feel really bad for the guy, and hopefully this will give him at least something to look forward to. I'm not really good when it comes to this kind of thing, but anything I can do to help.... I'm thinking about handing over the keys to the FrankenAxe to him so that he can try it out. We'll see how it goes...

-Ray

[Edwinssiv]

Ray-My condolences to your girl friend. I lost my Dad to cancer many years ago, so I understand how hard it is.
Glad to hear you are going to get her dad into the hobby….nothing like having someone to fly with! Not sure about giving him the Axe though…thought you liked the guy…rofl…he may get mad at you for getting him addicted and then getting him spending all his money on keeping his heli up in the air!:cheers
Hopefully you get some flying time in soon…it looks like we are close to being over our spring time winds so I may get more flight time in now.
I have the Axe pretty much flying great right now...did some more hovering in the house last night after I got home.

[markind]

Sorry for sad news old bean, cancer is indeed a *****. RIP Mom. RIP Dad. RIP Uncle Bill. RIP Aunt Rose. RIP Cousin Gary. RIP Ken (best friend's dad). RIP Judy (best friend's mom). RIP Laura (close neighbor). Yeah I know more about chemo than any should have to... but enough buzzkill! I've got heli news!

The SoFA flies!

Yep I got into the clubhouse tonight, and spooled her up. Made some throttle/pitch curve tweaks, and slid and hopped around a bit. Remarkable! The cyclic responds right with right input, left with left, and so on - not too shabby!

A couple more radio tweaks to bring down the headspeed - seems too high for these plastic trainer blades - and I went for the hover. Sweet! I immediately shed the Training Gear. Not needed! :D All landings feather touch! Tracking is dialed!

Not nearly as obedient as the TREX, but manageable - and tail is fairly docile! The belt holds!!

The motor still gets pretty dang hot but if I limit the flights to 5 min, which is enough because I have 7 of these battery packs now, she should hang in there ok.

I hovered around a bit and flew in some swim left/right and some slow side-in passes and some half turns. The tail floated a bit here and there - I think the HS-55 is barely adequate and I just intended it for testing anyway.

Otherwise, I was really quite blown out. I did not expect nearly as good a performance right off the bench after all that work. I half expected a catastrophic failure in flight, but the belt mod holds!

I am really close to having a nice second bird in the flight bag - she can't tolerate any wind but I am looking forward to a calm day to get her outdoors now. Just need to get a better tail servo and I think she'll give decent patterns at the local park one day!

:woot

[markind]

Adding pics...