Raptor 50 "Super" Stretch

[AZ ChopperCam]

710's anyone?

got the parts in and I'll be doing a super stretch to one of the RaptorCams. I still use an Ergo 60 boom but do not cut it.

It will clear 710 mains and 105 tails

I figure an Actro 24-6 on 10S with 8.5:1 will spin 710's nicely at about 1600 rpm. Or even a 32-4 on 9.56:1 gearing and dialed down a bit should give the same.


I need to pick up an Actro to test it but I think the extra blade length will help in autos and hauling around heavier cameras like the HC-1 and fullsize DSLR's

[miami6]

i am running 710's on my r50 but it is powered by a C-Spec 91 Viperhead engine

i would like ot go electric but the gearing is what I think will keep me from finding the proper motor setup

let me know how that actro works out

[GGoodrum]

Well, since Tabb, and others, have used 24-5's on Maxi-Jokers with 800mm+ blades, I'd say the 32-4 would work fine, but is probably a bit on the big side. Forget the 24-6. You will have a VERY hard time finding any of those over here, and I'm not even sure they make a Heli version. Besides, on 10s, the best you will be able to do is about 1500 rpm.

The A50-12L would certainly work with 710s. Since it is as beefy as the 32-4, it should work fine.

-- Gary

[AZ ChopperCam]

hmmm... Ok maybe I'll give it a go with the Hacker. I've been wanting to try an Actro in a Raptor just to see what the other options are for AP/AV and not be locked down to just one brand.

but for the time being I'll see how the A50 handles the 710's

[epc2]

24-5 and you can use a jazz or Schulze esc.

epc2.

[GJestico]

Is that still using the rap 50 6mm spindle and thrust bearings ?

[fitenfyr]

Is that still using the rap 50 6mm spindle and thrust bearings ?

I agree this could be a BIG issue.

It is starting to sound like JR ship I know of that was a bit abitious on the head. :D

I would certainly up that rotorhead to the 60/90 head before you go bolting anything bigger than the 620's on there.

[AZ ChopperCam]

you guys are overly worried. I can gaurantee you that the head is up to the task. There are guys flying 710's 3D with R50 head. I wouldn't do that of course but the ever so mild flying style that AV requires likley puts less stress on the head than 600's spinning at 2300 RPM

hell I'd put 790's on it if I could

[AZ ChopperCam]

according to some rudimentary calculations I just did my numbers show 200gram 710's spinning at 1500rpm put 70% of the load on the head as 150gram 600's at 2300rpm

this is not calculating the crazy gyrations and insane gyroscopic forces put on the head under extreme 3D flight by those 600's, but rather a simple centrifugal force calculation.

nope... nothing to worry about.

[askman]

yup. mv^2/R use Cg for calculation of V and R.

[AZ ChopperCam]

yes.. I used 55% span of the blades as that seems to be where they balance. I also assumed a rotor head width of about 150mm. I'm sure there is more to it but for rough numbers I think it works

I would certainly up that rotorhead to the 60/90 head before you go bolting anything bigger than the 620's on there.
awww come on Jason... what rock have you been hiding under?? :shock: I've been flying 180gram 680's on the Raptor 50 head (metal grips) for months now and it's working perfectly

[GJestico]

Problem is the spindle can be bent because of long lever arm of the long blades. With high headspeed you have strong force pulling blade straight. Low rpm tension force is less, spindle can bend.
I went through the same thing with my Raven 50 AP rig. 710 blades on 50 size head, 6mm spindle, 1500 RPM
It was no prob when O/A weight was 10 lbs, but at 12 lbs RTF spindles were bending in the mildest of flights. I did the same calcs re blade cent force for various sizes. Did not take into consideration the bending moment though.........
BTW 600's at 2300 rpm ? man let me hide behind the fence while you run that hehe. I bet the thrust bearings have dents in em. :bomb:

[AZ ChopperCam]

material properties/dimensions need to be entered into the equation if you want to start talking about spindle bending between brands. Comparing a Raven 50 spindle to a Raptor 50 spindle without all the numbers is fruitless.

do you happen to know the length of the Raven spindle? fulcrum points? I'd also like to know what material it is and if any treatment has been done to it... don't know how we can get that data but it would be interesting to do the math.

[GJestico]

dont know the material specifics. Who knows the raptor unit maybe stronger. But the are both chinese steel.........................
Raven spindle is 92mm from thrust bearing seat to seat

[AZ ChopperCam]

But the are both chinese steel...

what isn't anymore these days :roll: :roll: :roll:

[askman]

actually, china really don't make lot of steel. they do use up lot of it though.

http://en.wikipedia.org/wiki/List_of_steel_producers

heck, it should be easy enough to get hardened spindle shaft if necessary.

[lakespinner2]

FWIW. I'm not sure if it's pertinent but I just had my first ever blade departure a couple of days ago.

My newest R50 Titan (about 60 flights) tossed a blade (620 NHP's) in a flat hover at 2100 rpms (multigov) in a more or less flat hover. I'd been doing tic tocks and what little 3D I can manage right before that and I stopped to piro it around to bring it back closer to me and while it was basically flat and around hover pitch it just exploded.

So far the only thing I have found is a plastic stock grip that let the blade bolt get away. The top and bottom tips of the blade grip broke away right at the tip so the blade bolt tore out, and it was still in the blade nearly 300 feet away. The blade departed instantly, pretty high up; I was amazed at how far that blade went,

It was pretty exciting; luckily it was waay high and pretty far out over an enormous field. I wouldn't say it's 100% certain that the grip was the cause but so far it appears to be the culprit (or me, for running 620's at 2100 with plastic grips :) ) I have an all metal Kasama head that's going to replace it.

I've also been running 680 TT blades on a different raptor 50 with plastic grips and it does great (but at a lower headspeed); I might consider tossing some metal grips on it too. So far the tally is spindle failures - 0, plastic grips - 1. :)

I had just mentioned to a fellow at the field a couple hours earlier that I had never seen a blade thrown from a heli. sheesh :roll:

[WillJames]

OUCH, sorry to hear that Randy. Looking forward to yoru event in Sept!!

Got any pics of the grips to share?

[lakespinner2]

Will, I might be able to find one. :lol:

http://www.flyupyours.com/heli/titangrip.jpg

Yep, the fly-in is less than a month away, my goal (before the funfly) is to have this bird fixed, another gasser completed and now these guy have me itchin to get a logo or eRaptor for a midsize camera ship. work work work. :mrgreen:

And I want to THANK all the guys here :noteworthy for the AP testing they're doing with the electric helis. I went thru it with the t-rex's a year or two ago, as did most everyone else, and it's time consuming and expensive. I just want to thank everyone for sharing the results of all the testing with these larger electrics.

[AZ ChopperCam]

it's time consuming and expensive.

man.... you got that straight. I've had almost no social life for the past 4 months and if I added up what I've spent on R&D ...... don't even want to go there.

that pic of the blade grip is scary. I have one RaptorCam that has plastic grips. I think for the little cost that it is. I'll replace them with metal ones right away.

[fitenfyr]

DJ,
Not hiding under any rock been here the whole time enjoying your work.

You are certainly free to do as you like, but I myself would not even run the 680's on that head with a load.
I would switch over to the 60 head if I chose to run anything over 600's.
What does it hurt?
You add strength and you KNOW it is designed to work with 710's at headspeeds way higher than you want.
Should be an easy and simple swap to the 60/90 head and you could even still run the plastic grips and block at that point (assuming you keep the AUW down).

There are too many variables involved to take the risk with a 50 head in my opinion.
The spindle, grips, thrust bearings, plastic/metal fatigue in the head, etc...
All of these are engineered at the factory with a certain load, C.G., blade length, blade weight/C.G., etc. in mind. When you start to alter those significantly you are now changing several variables at once with unknown consequences.
Otherwise why would they bother to make a 60 kit?

I just had a set of TG 800's stress crack on my Ion simply because I was running the headspeed above the 1400 rpm that is apparently recommended by TG.
Didn't bend a single 5mm blade bolt or anything else on the Ion, but the one blade can be bent about 4" from the root and they both show multiple stress cracks down the span and length.
They were never crashed or abused and by my tach were run at a loaded 1550 RPM with AUW between 20 and 23lbs.
Well within what I would have called a reasonable range of operations.

Weren't you the one who said you got into the Raptors to reduce the risk of a crash?

Don't get me wrong I am not knocking your work, but you have progressed well beyond the risk you were taking with your gassers now in my opinion.

Just food for thought.
I myself will stay with my Joker and Ion.

[AZ ChopperCam]

you have progressed well beyond the risk you were taking with your gassers

so... putting less stress on the head than the typical hardcore 3D pilot puts on the head puts me "well beyond the risk" than what I had with my gassers?

Some of those guys fly 620's at 2100rpm+ and perform maneuvers that must be in excess of 8G's. I doubt I ever hit more than 2g's As you may recall from full scale training a 60° bank and maintaining of altitude is about 2g's I rarely bank past 45°.

what causes part failure is not single sustained loads but rather cycling of excessive loads... load on, load off, over and over again. My style of flying is so lazy and smooth I just don't imagine it causing failure.

man... sorry but I just don't see it. I've now got probably twice the flight time on these Raptors than I had with the gassers all last year. The gassers failed twice. Nothin' yet with the Raptors

[GJestico]

Love your work DJ, I wasnt trying to put down your methods......just giving you my experience to consider. Keep blazing the trail. Hope this doesnt turn into an argument

[AZ ChopperCam]

no offense taken at all... by you or Jason. I'm just saying I feel my Raptors are as reliable and robust or more so than one flown in a 3D profile. be it with 600's, 680's or 710's

[GGoodrum]

I think the head is fine. We've been running 2100+ setups with 600-620 blades for quite some time, and haven't had a single problem. As long as you have the metal hub, I think it will be fine. Just last weekend I video'd Jeff Fassbinder flying his newly converted Raptor Titan (Z50T, 11s-3700 FP Evo 20s...), with a set of the new TT 620 CF blades, and it had a headspeed over 2300 and +/- 13 degrees of pitch. He hit one peak of 3709W ( :shock: ), the most I've seen for anything other than a 12s-equipped Ion.

-- Gary