Raptor 50 won't lift off.

[Neil66]

Hi everyone, hope you can help because I'm absolutely stumped.
I bought this Raptor 2nd hand and I've had nothing but trouble, but that's by the by. The latest problem is it had some metal main blade grips on and the bearings were shot so as I have had to do with everything else I thought the best way was to put them back to standard. So I bought the plastic ones, put them on, setup for 0,5,9 and it won't leave the ground! It doesn't even seem to be light on the skids, I even tried adjusting the linkeages to give me far too much pitch and still wouldn't go up. Can anyone make any suggestions because I can't make it out,
Cheers
Neil.

[LAMAR COOLEY]

Neil66.
First I would recommend checking out http://raptortechnique.com
Mr. Mike Prewitt has an excellent site for raptors.
Assuming you have the proper mechanical setup
Ie. At mid stick ( cyclic) everything should be level ( swash, mixing arms, grips, paddles )
Grips (blades) and paddles should have "0" degrees of pitch at mid stick
Use the radio "pitch curves" to acheive the proper main rotor balde pitch angles ( plus and negative )
With +5 degrees of pitch ( for the beginner) at mid stick and have the engine tuned( and proper throttle linkage set up ) to give 50% power at mid stick then it should hover.
There are other things to look for and check out but "raptortechnique " should get you on your way.
Regards

[Neil66]

Thanks for your reply, I've spent quite a bit of time this afternoon on raptortechnique and I can't find anything like this, I should point out I'm not a beginner I've built loads of helis and I've never come across this, it really has me stumped. I keep going back to basics and starting over and you would think with 60% throttle and 5 degrees of pitch it would go up but it doesn't. Even when I increase power to 100% when it has got 9 degrees it doesn't. Is it possible that something could be stopping the pitch increasing when it gets up to speed?

Cheers

Neil.

[LAMAR COOLEY]

Sorry Neil,
I checked out your profile ( not much there ) and was not aware of your experience,
Yes your problem is a "Stumper".
Please, take no offense,
Just recently one of Helifreaks Professors posted a photo and asked if anyone could spot
the cause, which he and others had overlooked for quite a while, of a problem he was
having with the tail not holding. Turns out one of the tail rotor blades was on backwards.
Oh well.
Onward and upward.
That ( your ) baby should fly.
Recheck you radio "pitch" end points ( travel adjustment ) settings.
Recheck your blades.
Recheck servo direction.
Just trying to help sir.
Regards

[Neil66]

No need for appologies at all, I've made some pretty stupid mistakes myself in the past but always managed to laugh at them after. I did check that the blades were on the right way though! No the thing that's got me is it was flying with the metal blade grips on, albeit horribly but it was up. Apart from checking the tracking and pitch curve and upping the throttle a little I haven't really done anything else.
I feel sure it defies the laws of physics or something.

Thanks again.

[JEB123]

No need for appologies at all, I've made some pretty stupid mistakes myself in the past but always managed to laugh at them after. I did check that the blades were on the right way though! No the thing that's got me is it was flying with the metal blade grips on, albeit horribly but it was up. Apart from checking the tracking and pitch curve and upping the throttle a little I haven't really done anything else.
I feel sure it defies the laws of physics or something.

Thanks again.

Did you say you changed blade grips? They're probably on backwards. Make sure the ball links are towards the trailing edge. :thumbup:

[Neil66]

Yes I had to check that earler too but they are on right, thanks anyway.

Neil.

[psindrup]

No need for appologies at all, I've made some pretty stupid mistakes myself in the past but always managed to laugh at them after. I did check that the blades were on the right way though! No the thing that's got me is it was flying with the metal blade grips on, albeit horribly but it was up. Apart from checking the tracking and pitch curve and upping the throttle a little I haven't really done anything else.
I feel sure it defies the laws of physics or something.

Thanks again.

Have you checked for leading edge control (versus trailing edge control) so you are not in fact giving negative pitch when it should be positive (and visa versa)

Peter

[JEB123]

Have you checked for leading edge control (versus trailing edge control) so you are not in fact giving negative pitch when it should be positive (and visa versa)

Peter

Right, that's next. Disconnect your motor and check for positive pitch when applying pos collective.

[Neil66]

No it's all ok.
I've just had a thought!! I've always set my helis up as per Finless ie 0 degrees at half stick, but after reading raptortechnique setup tips I've gone for 5 degrees at half stick. (I should point out I've only ever had any joy with electrics in the past because I couldn't get used to all the tuning involved with nitros, but I am trying to learn) could it be that the clutch is slipping so although I've got bags of noise and smoke I might not have enough headspeed? Before you ask I haven't got a tacho but would it make sense to ramp up the throttle before bringing in the collective? Hope that makes sense.

[JEB123]

Anything's possible!

[Neil66]

.............But unlikely I expect.
Thanks for all your help I'll have another mess with it tomorrow and let you know.

Cheers for now

Neil.

[Nitroburning247]

I had the same problem a while back, My clutch was slipping. I replaced the clutch lining, and bam! lift off.

[virtual120]

Ive just had exactly the same problem on my Titan but it might be relevant here... I didnt have enough Pitch Curve setup on the radio. I increased the curves and hey presto!.

I also had the slipping clutch just recently. Its very obvious if the clutch is slipping as the sound the engine makes is horrible - it will scream with virtually no rotor spin.

One thing to check though - without the heli running, pitch up and down on the radio and check the direction of the leading and trailing edge of the blades. If wrong, reverse them.

Im no expert but it does sound just like the problem I had...

Good luck.

[vandelescrow]

Someone comented the link should be leading or folowing the blade grip, (sorry I forget what was said). This could be either way depending how the heli was set up. I noticed my R90 is completely oposite my R50 and the manuals show it this way. On the 90 the link leads and on the 50 it follows. Ive read somewhere, to get more precise lead lag, the link should be in front of the blade grip and a Raptor can be modified to be either way simply by rotating the flybar 180 degrees, and modifying the mixing arms so they do not bind.

So do check if your servo is reversed and I think you are on to something when you asked if the clutch could be slipping. You said you fly electrics, Nitros do not scream like elecrics do (head speed).

[Neil66]

Just to let everyone know I sussed it yesterday.
After I stripped the head, replaced the swash and all the linkages, fitted a complete new clutch and then started a new model from scratch on the radio and still no joy I had a thought............. Pitch Servo!
I couldn't believe it, the poor little 3001 just couldn't cope, swapped it for a Spektrum digi and it flies like a dream now.
Cheers for all the ideas and help.

Neil.

[JEB123]

Just to let everyone know I sussed it yesterday.
After I stripped the head, replaced the swash and all the linkages, fitted a complete new clutch and then started a new model from scratch on the radio and still no joy I had a thought............. Pitch Servo!
I couldn't believe it, the poor little 3001 just couldn't cope, swapped it for a Spektrum digi and it flies like a dream now.
Cheers for all the ideas and help.

Neil.

Congrats Neil! Good detective work. :cheers
Cheers!