First Heli build - Compy 300 FP

[mtnmole]

Well, as a brand new person in the heli hobby I decided that the best way to get to know the beast was to build one. That is of course after destroying one HBFP and getting another one. By "destroying" I mean I messed around with it so much and got so frustrated not knowing what I was doing or how it worked I dismantled it in the middle of winter. I had already picked up another used one that was set up correctly and had a few minor mods on it, the DD tail and a metal paddle control frame. It was a cheap buy and the best thing I ever did in this hobby. The HBFP I had I struggled with. I balanced the flybar and blades, made sure the pinion and gear meshed correctly and attempted to adjust the tracking. But the tracking never did come out very good, the blades were always off by 1/2-3/4 inch no matter what I tried. I learned to hover sort of on my original but it was never stable. Did much better on the new/old one to the point I did some forward flights and could bring it back without to much trouble most times.

This whole period I would read and read then read some more learning as much as I could. I got to know most of you here long before I ever posted. I felt I was too new and had nothing to offer. Then I pm'd Beedm, he encouraged me to open up a bit and post - so I did ;D. Now look what happened OK, enough history.

I was so intrigued by the thought of flying something I built I had to jump in with both feet and hope you all would save me from drowning. So here goes: I bought a Compy "deluxe" kit from http://www.aero-fever: www.aero-fever.net/product_info.php?cPath=19&products_id=641 This was going to be my base machine. I wanted brushless, belt tail and fixed pitch because I am a lousy pilot still.

I came to realize I would need some way to control this, so after talking to my wife and getting the official okey-dokey I ordered a Blade 400. I found a steal on one for $349.95. That did 2 things, it gave me a decent helicopter to grow into and an excellent transmitter for a beginner.

I got the Blade 400 on 2/17/09 along with some goodies from hobbycity and got my compy kit 2/21/09. Thought I was done with history didn't ya

I got to start on the compy kit today. I was stunned when I opened the box, no labels, no guide, and NO SCREWS!!!!! But there was a cd with decent build directions. Being one that is prone to losing screws so small I need to pick them up with a magnet I had enough foresight to order an extra screw kit and it was in there, YAY!!!!!

There really was very little organization in how the kit was laid out, for the first few steps I had to go through half the packages. Then the trouble started. In the second step I was to put belt guides on a platform/frame support - THEY WERE NOT THERE!!! Missing now 1) screws 2) belt guides with spacers and bearings - I was pissed.

Ok, here are some photos - this is the first time I have done this so bear with me. I decided even though I was missing the belt guides I would start and see what I could get done. So here we go:

First - Clean desk so I had room to work. I'm not neat - ok, I'm a pig - just ask my wife

Got my desk clean enough to work on and not lose anything - or so I thought. Here is the packages that came from areo-fever.



At this point I was impressed with the quality of the components - except for the canopy, it is cheap and nothing I will use for long. It won't last. CF tail boom, composite supports, CF sides with clean cuts through out. So lets jump in and pop the cd in to see what we have. Well, the cd had a 13 page manual for assembly and 10, really 10 demo videos of them flying around. That was it. No nuttcaze style videos or Doozer type instructions. Well, I'm in it for $125.00 counting shipping - I can do this!!!

Open 3 packages to get the first step done, screws, plastic parts bag and cf bag with the swashplate bracket in it.
Phew, first step done . Next step, look through every bag, the boxes again, back to the bags for those belt guides - No go, nada, not there.

What do I do? Do I stop or Mcgyver my first attempt - cripes I can't even fly yet. Mcgyver it is. I scanned through the rest of the manual looking for a parts list - none, of coarse. It's my karma. Guess that should have been my first step, but I'm a guy - no need for directions here. Persevere, that's my motto(kept telling myself that all afternoon).

Ok, enough whining. The kit started to go together really well. The directions were easy to follow. The parts were good quality, and I did not strip one screw - not one!!!!

Got a few basics done and started to put the frame together:

Going good so far - this is the basic frame minus the belt rollers. They are in a spot I can get to by pulling the main shaft and gear. Then I start looking for the boom mount - well, I found it. It was for a 4mm boom!!! Check it out, how am I supposed to make this work!!! That little end is where I'm supposed to mount this boom!!! NO WAY!!!!

Ok, get over it, add it to the list for aero-fever.
Put the skids together next, not to bad of quality. Similar to the super skid clones as far as weight and flexibility goes. The battery support/bottom frame piece mount to the skids as shown. the you mount to main body.


I was unsure at this point if I should continue without belt guides or boom mount. I decided to build the tail. I had no experience with a belt tail before so this was all new. Again, had to go through 3-4 packages to get started but then I all started to get better organized. There was about 15 packages to start with and at this point I'm down to 8 or so. Not near the searching for this small part or that screw. There were a few screws in each package relating to the parts in that package or the on coming up next. The bearings were laid out so you couldn't get them mixed up, that was awesome. There are 10 bearings throughout the heli. I thought that was good.



Got the tail all done, no missing parts thank gawd. The head is next, may as well keep going.
The head is a HBFP head with a little metal, this I know forwards, backwards, sideways, but mostly crashed ;D ;D




That's as far as I got tonight. I do have most of the stuff to go in it.


I'm not sure if I will be able to use everything. I went cheap on most of the components because this heli will get crashed. I bought most of the gear from hobbyking:

motor; www.hobbycity.com/hobbycity/store/uh_viewItem.asp?idProduct=5245 may be to big - it sits in the open and there is room but it weighs a ton. I didn't realize until I held it in my hands.

servos; www.hobbycity.com/hobbycity/store/uh_viewItem.asp?idProduct=662 The front servo won't quite fit the way I need it to. I will need to sand or dremel out the hole a mm or so.

esc; www.hobbycity.com/hobbycity/store/uh_viewItem.asp?idProduct=2163 Bought this going a little large, a 20 would have been good with the motor and servos but I was playing it safe. I also liked I can program it so just because I got a card to do that; www.hobbycity.com/hobbycity/store/uh_viewItem.asp?idProduct=2169

Rx; www.hobbycity.com/hobbycity/store/uh_viewItem.asp?idProduct=5251 I would have prefered a 6100e but this was $30.00 cheaper and it will be fine.

Tail servo: www.hobbycity.com/hobbycity/store/uh_viewItem.asp?idProduct=6607 Because it's fast and digital, and not too pricey.
Ordered 2 batteries also: www.hobbycity.com/hobbycity/store/uh_viewItem.asp?idProduct=7343 Fairly cheap and will get me in the air - I hope.

And lastly a xmhobbies gyro: www.cnchelicopter.com/servlet/the-1403/xmhobbies-digital-gyro-G401B/Detail A lot of people raved about this so one late, late night......impulse buy!!!


This is my first attempt, I am claiming no knowledge of what I have ventured into. I am looking to all of you who know my mistakes before I do to help me out here. My next installment will be after I get the rest of my parts from Aero-fever. My recommendation is not to use them at this point. Slow shipping and missing parts, but time will tell. All the part BUT the canopy seem top rate, but I will need to crash it first to be sure ;D

I thought about adding up the cost so far and decided against it, I really don't want to know. My credit card is already screaming at me for the past 2 months of this hobby.

Dave

[Doozer]

very nice Dave, great photos. You will find that the knowledge you gain here will follow you in the rest of your builds. The fiber frame upgrade is my favorite heli. Mine is giving me issues tonight.

If I would have seen this before the Guru-z, I would have built this. I'm jealous of the screws! You're doing good man. Nothing to add so far. when you do this, you find your mistakes very quickly and that's where you really learn.

[kiwi1080]

You really have jumped in with both feet there, looks like a lot of screws and work, but it is very rewarding when you get that thing all together and realise you are smarter than you thought you were. Well that was me anyway ;D. Building really is a great way to learn the heli, when you get it RTF you are too afraid to start pulling things apart for fear of not knowing where the hell it came from!! I just bought the DX6i too so will be a new learning experience for me also. Keep up the good work, great photos and a nice new build for the forum.

[Solitaire]

Dave

We haven't heard how you're doing on the project for a few days. Keep us posted on your progress.

[mtnmole]

I got everything I could done, now I am waiting for the missing pcs. Need the belt roller bearings and the 12mm mount for the tail boom. I got ahold of Aero-fever and they shipped the parts out Tuesday 2/24. Should be here in a week or so and I can go on. Bummer to have to wait My luck with Hong Kong has not been very good this week, between missing parts and the batteries.

Luckily for me the weather has not been great either. It's waiting for my heli to be done

[Doozer]

Getting all of the parts in any of these kits seems to be a real issue. The Guru-z product line has had some issues with this as well. With my Neon... the belt guides were missing. With the Xeon, the bearings were missing.

I'm feeling your pain.....

[mtnmole]

Finally got my parts(almost all of them ). I received the correct tail boom mount and the pulleys. This was enough to finish the build I thought. Since this was/is my first belt drive build I really had no clue what to look for in the kit, now I know.

I installed all the servos, motor, Rx, and other misc goodies. After I received the order from Aero-fever I found I was also missing the ball end and connecting rod for one end of the tail control shaft. I ordered an HDX450 link kit from Kyle at the same time I ordered the motor. The connecting rod worked well but the ball link was WAY too big. Since all I was missing was the correct sized link and servo ball to finish this I ran to the LHS and bought a ball and link for a Blade 400 and they worked fine to finish the tail linkage.



After this I fired it up and the motor I had originally purchased was way to strong. I had to pick a smaller one to put in. I ended up going with store.rcsupersales.net/servlet/-strse-1488/4500KV-Brushless-Outrunner-Motor/Detail

The new motor is 30 grams lighter which is a good thing.



Finally done!!! Just need to trim it and put the grommets on the canopy.








Trouble now and I have no clue what to do. In order to keep it from spinning HARD left from motor torque the tail servo needs to be trimmed all the way to the fin side of the tail linkage:
Notice that the linkage is all the way to the right. How do I correct this to center the linkage on the shaft?

I have done several things to try and fix this: First I tightened the belt because it had some slip, not much but enough to skip a tooth now and again. Second I tried reversing the tail direction from counter-clockwise to clockwise spinning. This made it noticeably worse(even after I turned the tail fins the right way ). Turned the tail fins back around and switched the belt back to where it should be(counterclockwise spin) and trimmed it out so I had some right/left stick control. When I apply power and make it light on the skids I still need to put half rudder stick to the right to keep it tail-in. I'm afraid if I put the gyro on like this it will burn up the tail servo in short order, it only is allowed to throw one direction, the other input just bends the control shaft. Help please!!!! What did I set up wrong?? There doesn't appear to be a way to adjust the tail grips to turn them one way or the other.

[Solitaire]

According to what I've read on the tail setups for these things is there is a 6 degree offset built into it to counteract the torque. Also, the finished product will have the slider not quite in the center of the shaft. You'll have to either slide the tail servo towards the front, or if not enough room to slide it, then the linkage will have to be shortened.

Ideally, you want the tail servo horn and the slider horn at 90 degrees to the boom. The slider will be slightly off center on the shaft and you can set up the travel adjust in the radio if there is any binding.

Looks good other than that, Dave. I see you went with the CNC main gear/belt pulley. I did the same with mine. I put the metal belt guides on, too after I trashed the plastic ones.

[mtnmole]

Thanks for the input Sol. The servo is mounted in the frame so the linkage is the easiest to adjust. I have the servo horn set to as close to 90 as possible when the servo is centered.

Right now I am using the stock wood blades that came with the kit as well as the tail fins that came with it. If you look closely at the last photo of the tail it appears that the tail blades need to be in the 10-15 degree range to counteract the main blade torque.

I adjusted the servo throw in the Tx by dropping it to 80%, that keeps left from bottoming out, but there is no room to the right, well 1-2 mm I guess, but that's it(from looking at the tail, the stick is opposite, left stick-right throw/right stick-left throw correct?). Is there a way to adjust servo throw in one direction from center? As far as I can tell it would make no difference if I changed the grips around or if can even do that, but I may take the outside linkage apart to see if I missed something.

Right now my COG setup as shown is dead on and there is no vibration after the main blades spin up so that is a plus. I was worried about the batteries being to heavy but that doesn't look to be an issue, it is very light on the skids at 40% throttle and 45% will lift it up. Although right now it looks kinda like a spinning top with the linkage where it should be

[Solitaire]

Ok, I'm getting a better picture here.
So, you have to have the tail blades in the position they are in the last pic for them to hold the tail. There's not a lot you can do since the tail revs are directly linked to the main. You'd need to bring up the revs on the main to get better tail authority, and a couple of other things can be done, although these kits have worked fine for hundreds of users as stock.

Change the ratio of the tail gear (12T to 10T) or run a lesser degree of main blade to get higher headspeed. Maybe something in the range of 60-65% throttle for liftoff. They also have a 42T (40T is stock) belt pulley, but I don't think that's available in the CNC setup. There are more efficient tailblades available as well. The 2nd option is what I'd try first as it's the simplest.

Your directions are fine,

left stick-right throw/right stick-left throw

and turning the grips around won't do anything. As far as I can tell, there's no offset in the grips themselves.

On CG, I'm using a 1350mAh 15C at 105 grams weight and it's mounted about as far forward as I can get it using the extended battery tray (same as yours). I may have to go to a 20C for a better comfort level with positioning. My tail servo is boom mounted and I have a metal tail, so a bit more aft weight to counteract.

[mtnmole]

I'm pretty sure since this is my first venture into a belt tail I have something out of whack. I know and have seen videos of this kit flying beautifully, that's why I went this way. I'm going to pull it apart and see if my grips follow the directions to the letter. I did go back over the belt guides and had the bearings backwards. What I mean is the spacer was supposed to be on the frame side and not the screw side so I need to switch those. Right now the bearing is inside and the spacer on the screw side. May not be a huge deal short term, but may be down the road.

Just for the heck of it I put it assembled on a scale and it came in at 407 grams, a little more than I thought. But, 25% of that is battery.

I am done with Aero-fever. Not because of the tail issue but because of the missing parts issue. When I crash and need parts I will replace with Guru-z stuff and see how that goes. Some parts of the frame appear more thought out on the Compy but as far as the tail is concerned Guru looks to be identical. I really like the longer bottom piece/battery mount on the Compy though. Even if I need to beef it up some, it sags with my battery mounted. I have some 4mm CF tubing that would be perfect strapped underneath for more support and won't add much more weight.

[Solitaire]

I agree this should run close to true right out of the box.
I keep looking at your last pic with the suspicion there is something out of whack. As the slider gets pushed away from the tailcase, the blades should twist with the leading edge moving towards the boom. I think yours is backwards. Did you install the balls on the yoke on the proper side? This is about the only way you can get it backwards, I think.

<edit> Nah forget that idea. That doesn't make any sense. I just remember putting mine together for the first time and I had something reversed.

Looking closer at the plastic tail here, there IS a bit of an offset to the blade grips, so try reversing them on the yoke.

[mtnmole]

Tore the tail apart and everything was correct as far as I could tell. But the movement of the blades was opposite of what you mentioned Sol. When I move the slider to boom it pulls the leading edge of the tail blades in. There is no way to make it reverse that motion that I could see. What am I missing?

Slider all the way to boom


Slider all the way away from boom


I will order the tail gear(10T) and tail belt drive gear(42T) if you think that is what I need to do, less than $10.00 with shipping so not bad.

[Solitaire]

Crap, now I'm confused. Doesn't take much, trust me.

Yours IS correct. Slider towards boom, heli yaws right and vice versa. Not sure what I was looking at earlier. And yours has about the same travel mine has.
Soooo, where to now. If you have horns at 90 degrees and slider just about centered, and you have full range without binding, then it has to be a speed problem in the tailblades. Not enough rotation to move the air.

I think I'd try to get the headspeed up before changing out tail parts. I suppose a test would be to leave the blades off (make sure there is no positive angle to the flybar paddles) and rev the thing up. See if you can get right and left movement on the heli with stick.

If you still have to give it full rudder to counteract torque, check to see how tight the rotor turns. Try rotating it by hand (power off, of course) It may be too tight, although with bearings, this shouldn't be a problem.

If no problem there, recheck the belt. Just enough tension to keep it in the guides.

After that, I'm out of ideas. The guys that changed out their gear ratios basically wanted more tail control, not having the same issue you have.

Oh, one more thing...are your servo wires clear of the motor? Can't really tell from the pic, but since the outer can rotates, anything rubbing up against it...well you know what I'm getting at.

I'll think some more on this tail issue.

[kiwi1080]

What gyro are you using on that? Never mind I went back and read your post! I just had issues with tail spinning like crazy and all it was, embarrased to say, is making sure the reversal switch on the DX6i is set to N and then try flicking the reversal switch on the gyro itself. This instantly fixed my problem. Where is the gyro set on your heli, I can't see it on the pics you put up. Try to get it as center as possible and then try the reversal switch thing. Also try increasing the % on the gyro setting from 50% up to about %65-70 and then move the heli side to side by hand. When you move it to the left, the servo arm should move forward. These things fixed mine perfectly, I am using the Telebee but it isn't too much different. Hope that helps out.