Anwar, Rotorzone,
How tough is it to build a Heli from a kit. I mean i am an absolute beginner at Helis, but have considerable experience with airplanes ( kits, scratch builds etc ) . so have the tools, and skill set . But since i do not have an heli flyer around me. should i prefer an ARF, or a kit , or perhaps a kit built by someone ( I am sure Rotorzone, or Rotor would be willing to help assemble the kit ) .
Wow, seems like i am pretty close to acquiring my first Heli !!!
-Gaurav

Note: I took the liberty of splitting the topic, since building a heli for the first time is a subject of discussion in itself.

If you follow the instructions (including the ones with the stars and the fine print) strictly in the manual, and if you have some experience building RC stuff, it is quite OK for someone to build a heli for the first time on their own.  I have seen people do that very successfully.

I have also seen people build their first heli without enough thought or care, and the result was that parts started flying once they started flying it.

Some important things to note are :

1) Thread-lock : It is extremely important that any metal to metal screw/nut is fixed after applying some "semi-permanent / medium" thread locker to the last 2 or 3 turns/threads of the screw. You have to use good quality thread-lock. If you are not careful about this, the heli will cause serious grief.  And do not over apply thread lock either, only the last couple of threads.  Also, this is not for screws that go into plastic.  Note that there is also "permanent" threadlock, and that will not come out easily at all in case you want to change a part after a crash, and will force you to heat the part to get the screw out. There are some joints (especially in the head assembly), where it makes sense to use the permanent one.

I use a brand called Pacer Z-42 Blue threadlock for all my builds, and for any "permanent" fixing the Pacer Z-71 Red is used. Use a good brand, or you will be sorry.

2) Do not over tighten screws, as they can strip easily.  It is even more easy for screws that go into plastic to strip the plastic holes.

The real challenge is not just building a heli from the parts, but in setting it up properly and then programming the radio accordingly.  Look up the Bob "Finless" White build videos on http://www.helifreak.com, they are the most widely used build instructions for helis.  I saw the build videos for my Trex 600 electric heli, before I started on my first ever build.

Ha thread lock!!! Just had a frustrating experience with it. I was overzealous in using thread lock in the spindle screw in my Knight. Considering the criticality of this part I had wetted the entire thread with thread lock. It was as good as welded. I stripped the hex head trying to remove it. Then cut a slot and stripped that too. Cut another slot 90deg to it and stripped that too, the screw had no intentions of budging. Had tried heating with a soldering iron too to no avail. Finally had to grind the head off to remove the spindle. So as Anwar said, use thread lock, but only on 2-3 threads no more. That is usually enough. In Knight the spindle screw is 5mm compared to the 3mm ones used in Raptor, that also might have been a reason it is stuck so well together.

Also thread lock will break down plastic parts, so never use it on plastic.

You need some extra tools that you normally wouldn't have if you are building planes.

1. Pitch gauge
2. Ball link plier
3. 1.5,2and 2.5mm Allen keys of good quality.
4. The ball version of allen key for atleast 2.5mm size.
5. A spirit level that you can hang on the flybar is useful to have. I'll post another thread how I use it to setup a heli soon.
6. Crank lock tool to fix the fan hub and engine nut. I use a home made one.
7. Vernier calipers would be easier, but you can also do with a simple scale for measuring links.
8. Hex starter shaft

Some fuel pumps leak more with nitro fuel in my experience. (atleast the cheap hobbico one did that for me). You might want to get a good one. The one that comes with TT carrymaster has worked well for me. Also the MK one.

All the information needed to build a kit yourself is available online and in the manual. It is upto the individual to take the effort to read and understand. Seeing one and having local help certainly makes things a lot easier.

6. Crank lock tool.

My personal experience and from many others I fly with, we are able to tighten the engine nut without having to lock the crank.  For others, creative use of an old toothbrush handle was the worst that was needed 

Even I used toothbrush for my first heli assembly. But using a crank lock eases my mind since I don't have to put stress on any part that was not made for it. It was cheap enough to make one (Rs 100 will get you enough material to make 6 crank locks) that it was an easy decision for me to go that way.

Quick update here. Looks like i am going in for a Raptor 50 Kit. I will create a build thread here, and will keep my progress posted. Will need substantial help from forum members too.  However this might be a long drawn out project, since i have extensive travels coming up next month, and i will be collecting the engine/servos necessary tools to build this, but the good thing is that this is happening !
-Gaurav

Good decision   

I have not built a Raptor 50 from scratch myself, but have tuned and fixed various aspects on it multiples times (my brother is also using one he got second-hand from someone as his training heli).

Rajesh/Rotozone would be familiar with all aspects of the build, as he has been playing with them forever   Together, we should be able to help with pretty much any concern you have.

Keep us updated as you progress !

Quick question (may be silly),
How much of space/open area would you recommend i would need to practise hovering on my Raptor 50 ?
I have practised on Realflight and can hold a hover their confortable at one point.
Reason for my asking, i have a ground very near to my home, and would be something like 150x150 feet ( i know its not huge ) .Would it be safe to test this setup there ?

For just hovering, that is plenty. If the ground is open to public, have somebody else with you to keep onlookers away. Most people are too curious and are not aware how dangerous it can be to get close. Safety aspect will give you more tension than flying.

Looks like you finished building quietly. If the setup was good, it'll hover with hardly any trim needed if at all. If not be careful, flying an untrimmed heli could induce mistakes in a newbie.

You should definitely post some pictures 

Also, you can get a pretty good idea about any trim required initially by looking at how level the swash plate is.  You can eyeball it to get pretty close. If you want to bring closer to perfection, judicious use of a bubble level helps.

Here's a trick I have picked up for swash plate leveling with the pitch gauge. Measure the pitch on the one of the blades at every 90deg of rotation. If it is not the same at all positions your swash plate is not level. You can check this at different pitch positions to check for eCCPM interaction (not relevant for Raptor here). If you do this and also make sure pitch in both the blades are same, you'll likely get a heli that doesn't need trims.

Cool ! Never thought of doing it that way 

For CCPM interactions, it would be simpler to put the pitch gauge on the flybar paddle, and move to the extreme pitch ranges watching out for non-zero pitch readings.  The fact that all you need to watch is "zero pitch", should make it easy (as compared to some non-zero pitch reading on the main blade).

How exactly do you do it ? I assumed we will not get zero paddle pitch through out the pitch range because of phasing. Do you first find the phase where there is minimum pitch change and then try to zero it out ?

I typically do it with a bubble level on the paddle (got to try your suggestion of using the pitch gauge itself).  Picked this up from a Finless Bob video on helifreak.com.

At center stick, the paddle should have zero pitch (bubble level should be right in the middle).  Now if I go to max positive pitch, it should still remain the same.  If the bubble level shows displacement, then dial in appropriate end-points for the servos in question to remove the interaction. Repeat the process for max negative pitch.  Then repeat it all after rotating the blades/flybar by 90 degrees.

BTW, you have to be near perfect on main blade pitch setup (linkage adjustments etc), before you attempt to fix CCPM interactions this way.

Ok, I had typed in the middle of something else. I had aileron-elevator interaction on my mind and hence the phasing thing. Ignore my previous post, only good thing it did was to make Anwar give a good explanation.