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chilipepper
06-06-2005, 03:40 PM
I'm pretty sure I have a bit of a woof going on and I need some advice. I've read through a previous post:

http://www.helifreak.com/about1722.html

This article had some really good discussion but I'm leaning a little towards a loose head instead of the blades, dampers, etc. listed there. It was pretty bad with the woodies while hovering and I noticed it mostly when flying in some wind (15mph). I'd be going along fine and then it would just go way out of track and drop. I was able to keep control of the decent and put it back on the ground. (BTW, Iím about 2 gallons into this great hobby!)

Slowing the head speed and some negative collective while on the ground would stabilize the head again and it would be fine for a bit and eventually would do it again. I followed much of the advice of the previous article and checked blade balance that was fine. I had a new spindle shaft on hand so I installed it and lubed the dampers at the same time to eliminate that possibility.

I took it back out and almost had a full tank through it and then it woof'd again. I then switched to carbon blades as suggested and although the woof is almost inaudible and undetectable I think that it still is there a little bit. What makes me think this is a vibration will occur suddenly and then it will loose altitude as if the head speed dropped. Since the carbon blades are much more rigid it isn't as dramatic but I think it is still there.

Tracking is very good and checked and double checked. My only suspect now is that I noticed the main rotor hub has a little play on the main shaft. The play is not up and down but side to side along the main blade axis - if you put one hand on each of the main blade grips you can move them a little up and down in a seesaw motion and the play is in the hub.

I have a new hub on order and will replace it as well as the dampers since I'm taking it all apart anyway. Does this sound correct or does anyone have any other ideas or experiences to share with me. I think I'm running out of options.

Thanks!

Raptor 50 v2 conversion
OS 50H
Futaba 9c
401/9254
9202's everywhere else

blakka_1
06-06-2005, 04:01 PM
Definatley change to new dampers, the new hub and dampers should make the head stiff again and should get rid of lots of play. The plastic Raptor hub is known to develop play in it after a while, I changed to a metal hub because of this problem, however a new hub and dampers should keep your head nice and stiff with no play for a long time.

To eliminate even more flex from the raptor head, I would recommend you try the red dampers, the standard dampers supplied with the Raptor are blue, there are red ones avaliable which are much stiffer. Try the red dampers out. :)

You can order some red TT dampers here - http://www.ronlund.com/Merchant2/merchant.mv?Screen=PROD&Store_Code=heli&Product_Code=ACEPV0382

Worn out dampers can cause woof and poof. :)

PS. Here is a pic of the new hub and dampers which I ordered for my Rappy not long ago, I to had some play in my head, my worn out dampers did cause my Rappy to flutter much more. http://www.helifreak.com/album_mod/upload/7c97a26e9900e4802c855933ce2627ae.jpg

chilipepper
06-06-2005, 04:19 PM
Nigel,

Thanks for the quick reply - Is the aluminum hub worth the extra cash (approximately 10x)?? I've got the new dampers and hub on order to hopefully get me through this weekends FF. Thank god the woof didn't turn to poof but I wasn't doing anything too radical so it stayed pretty much under control - just shook the pilot more than anything. :shock:

I would like to go back to the woodies however - Do you think I was correct in that the carbon blades didn't react so violently due to their stiffness versus the woodies??

Thanks again!

blakka_1
06-06-2005, 05:03 PM
Is the aluminum hub worth the extra cash


To be honest I really think it depends on what level of flying you are at. If just hovering and sport flying then the difference between the metal hub and plastic hub is not noticable, in this case the plastic hub is more then up to the job. However when flying the heli harder and doing 3D then I would say yes the metal hub is worth the extra cash as it makes the heli more precise and much sharper during 3D flight. When flying hard the plastic hub will develop play after a period of time, but if sport flying or hovering then the plastic hub will last a long time, and therefore in that case I think the metal hub is not needed. So really depends on what level you are at mate. The metal hub just doesn't wear, always feels stiff. I had my plastic hub for a year before it developed play so I personally think the plastic head does well. :)

About the blades scenario, yeah the woodies flex more then carbons and so when the heli woof's and flutters the woodies would most probably flex too making the heli act even more violently. I would think that your right on that one there mate.

Hope that helped. :)

johndale
06-07-2005, 06:25 PM
I had a bad woof and puff with both of my 50 V2 until I changed my mainrotor blades. I was flying Mavikk blades (woodies'Glass and carbons) I was told buy heliproz that it was my ship and that was over a year ago and when I put TT blades back on it went away. So what brand of blades are you running?

chilipepper
06-08-2005, 09:20 AM
Hmmmm... Ironically I was running mavrikk woodies! Maybe your on to something! :?

I have a set of the TT carbon blades that I'm running now and I think the problem is really almost gone as far as caring about it goes. It will be interesting when I get the new rotor hub here if that tightens it up substantially as well.

Realistically the $70 for the TT carbon fiber blades isn't too bad. That is also interesting that the Mavrikk CF blades gave you grief. They seem to be pretty well made. A friend of mine has them on his heli but doen't have too many flights on it to really know how they work (no woof's as of yet though).

WillJames
06-08-2005, 09:24 AM
I ran the Mavrikk carbon blades before on my R60's with no trouble other than my thumbs for a few sets. I was running the Rick's Dampeners with the plastic and then the metal QUK heads with them.

chilipepper
06-08-2005, 09:31 AM
Tee Hee! :D Maybe someone needs to design some carbon fiber thumb/finger implants that are neurally isolated from the pocket book and fully 3D ready!!

Thanks for the info!

johndale
06-08-2005, 10:19 AM
:cool: The only time I had problems with the mavrikk blades is when I went into transitional lift from forward flight. That was on the carbons and glass blades. The woodies were junk. Like most people learning to fly you want the woodies so WHEN you crash it isn't a total waste. The woodies caused almost everyone of my crashs because they would inflate either one of them or both. They were sealed and I took a heat gun to make sure they were tight per Heliproz and it did not matter. I was told it was my head and a bunch of other things. I went back to TT and the problem went away. I am still flying the same heads on both of my 50s. One is metal and the other is plastic.I now get my spares from Clark at WWW.onlyraptors.com . If he sells you something he stands behind it because with this hobby it is to dangerous to stand in frount of it. Just a little of humor. You may want too try the Russel deakin Mod on you low side needle it really helps and gives you a lot more power and you will fly a lot longer. :glasses2:

chilipepper
06-08-2005, 02:50 PM
Yeah kind of a conundrum - More you pay, better it flies but more it costs to fix... less you pay, worse it flies but cheaper to fix. I guess like everyone says it is an expensive hobby period do you just have to deal with it!

Do you have a link to more information on the Russel deakin Mod??? I'm not familiar with it and search only gave me one other thread you posted about it. But I'm always interested in tweaking with things!!

Thanks

johndale
06-08-2005, 03:41 PM
The tip is 0.8mm and the taper is a straightline taper for 2.5mm's back into the needle...

At 2.5mm the needle is the original size... 1mm thick
I did this to one of my 50's V2 and it really does work very well. it now really wants to go straight up like a rocket. Put the needle in a drill and using a fine file turn it down slowly and watch the magic. I done #2 Raptor now and I did get a second needle from Clark at www.onlyraptors.com just in case I screwed up and went to far but I did not. This works VERY well . This is a must mod and the new low side needle has 2 orings on it for better sealing. You will get 20 to 25% more flight time with this mod. I had this posted a long time ago and I feel it will help a lot of fliers. http://www.rchelispot.com/viewtopic.php?t=1430 this web page has a picture of a needle that was done. Believe me it really works. All you have to do is put the needle in a cordless drill and use a real fine file and turn away and you will get the tapper you need. Once you see the difference in the shape of the needle you can see how it works. :glasses2:

H2daB
06-13-2005, 04:59 PM
I fly the TT carbons. However the TT woodies are great blades for the beginner. I know several guys that fly or have flown the TT wood with absolutly no problems on the 50. However, the mavrick blades did cause a couple of the guys some serious problems. At higher RPM they would go out of track. I'm not sure why this happens, but it did on more than one set. some of the guys flew the mavricks on the 30 with no problems at all, even at higher head speeds. A mystery to me. The best all around blade for your money is TT corbons at around $70 a set, you can't beat 'em.

Ben webb