Question on boom length

[Luvmyhelis]

Just got a box of parts from Peak, man that was fast. Thanks Chuck for your help, advice, and extra stuff you supplied!

But I need to know the exact length of the Diabolo 700 boom if anyone has those numbers handy? I have a new 700 belt and gears as I decided to field my rebuild as a 700 instead of an 8 Tri. And am wanting to field test a new kind of CF boom on it, but it is 1000mm long. I could cut and test until I got the length right. But don't want to waste the time nor stir up too much CF dust in the process.

Other questions. What hs are you guys finding works with the 700 Tri, and again as a two bladed head version? I intend to try both.

This may end up being a slow process. But at least I can get started with what I have.

Thanks for any help I can get. You guys in this section rock.....

[KBaksh]

911mm long on the 700 boom

[Luvmyhelis]

Originally Posted by KBaksh

911mm long on the 700 boom

Thanks for the quick post! Time to do some trimming.

[nooobs]

...

[KBaksh]

Is the carbon fiber boom lighter than the stock boom, also what's the benefit of using carbon fiber boom.

[Luvmyhelis]

Originally Posted by KBaksh

Is the carbon fiber boom lighter than the stock boom, also what's the benefit of using carbon fiber boom.

It is more rigid, lighter, and the one I am trying is as stiff as a baseball bat. Very high quality CF. I will find out today if it flies without any issues.

[Luvmyhelis]

Whoooot! After almost 3 full days of working on my Triabolo and some seriously late nights.

Here is my prognosis with the CF boom. Obtained here: http://www.flycarbon.com/1000mm--30m...atte_p_79.html

Flies like a champ. Zero issues.

Here is my setup. Koz 800-40 17t

A set of mismatched Koll balanced Edge 713s, so they do match perfectly now. But one way waaay off in weight till it got a work over, and of course the Triabolo blade notch.

I ordered in both tail ratio gears for the 700 so I could have the option of flying this as a two bladed head if needed. Or? If the larger gear didn't have enough authority with my triple Kbdd 112s in place with the RcTek tri tail. Which I rebuilt. Turns out it works perfectly with the higher tooth count gear. No tail wag under full pitch pumps at all.

New 700 tail belt and primary tail drive gear. While I had the new belt out, I added a dose of White Lightning wax lube. it appears it is totally different in tooth design as well as what the belt is made out of vs the 800 belt. The gears are also different. As the 800 has a more aggressive belt design.
A few new bearings as needed. Lucky I keep a fairly large assortment of various sizes for my fleet. I robbed a few from other models that fit perfectly. I did rebuild and straighten all three aluminum Triple grip arms. It is what I do since I can work or straighten almost any metal. My original turnbuckle links were blown off in the head explosion, so I spent some serious time working over some Traxxis links that finally fit the two grip to swash link setups.
I didn't have any real clue I would get this far or I would have ordered the correct ones.
Turns out I found a set of new head pins in my parts collection I forgot I had, and enough stuff to rebuild the damaged grips. Thanks to Chuck for the new Tri head hub! Once I saw that, one thing led to another and it was build frenzy time.

I used the Soko tool and levelling table to setup the Tri pitch on the grips, and let me tell you this is as accurate as it gets, since the Diabolo helis don't have any slop like other mass produced helis. Wiggling the grips only deviated the Soko by a tenth of a degree either way. Plus with the Soko, it isn't based off the blades. Which can induce error. Each grip was dead on true gravity zero. Blades tracked like a razor when I spooled it up.

I did cut the new CF boom down to 915mm, just to give myself a touch of extra space if needed. I didn't. It fit like a glove up front, and slipped into the rear tail hub with some minor sanding. Then I found two of the stiffest CF boom support rods I could. I ran these longer than stock, as Gerd and Chuck had me kinda paranoid about boom control and wacky issues. Then I added in an OMG boom strut support bracket, just to eliminate boom vibrations.
Gerd's tests with CF booms ended in disaster. Good day here as mine didn't, far from it.

As rigid as this boom is, it probably doesn't even need the support struts. I will remove the struts and I will test this weekend to find out!

Here is my flight test.

Spun her up to 1550 in norm. Perfect.
Spun her up to 1700 in ID1. Perfect. And I gave it numerous pitch pumps and aileron/elev commands, along with violent tail moves. Perfect.
Spun her up to 1800, and did the same thing. Smooth as butter and extremely well behaved!

Other than the scarred up old Fusano canopy, which has survived a couple rough landings.

Gotta say, I like it! And seriously like the new look much better than the old boring metal tail boom. Zero hassle, no paper cardboard insert needed. No belt induced static sparks.

And by the looks of it. My very sensitive Skookum 720 vibe logging gives me a clean bill of health!

[KBaksh]

That's great news and the heli looks good. I wanted to do a carbon fiber boom but my concern was too stiff boom with the rigid frame might introduced vibration. I notice you have standard flybar blades, the Tri-Blade is a different design with lighter blades I think.

[Raptorapture]

Great to see you're back in the air with the Tri. Looks nice!

[Luvmyhelis]

Originally Posted by KBaksh

That's great news and the heli looks good. I wanted to do a carbon fiber boom but my concern was too stiff boom with the rigid frame might introduced vibration. I notice you have standard flybar blades, the Tri-Blade is a different design with lighter blades I think.

They (fb blades) I have, just respond with a quicker motion, I find the fbl versions were heavier and slower on the cyclic. More stable though.. The NHPs are stlll heavy in a way, but flex more? Which is easier on the rigid head. But I am slowly saving my pennies to acquire some great matched NHP blades from Peak when I can. I have never flown any 500, 600, or 700 size heli that is so quiet and has virtually zero head vibes, even in 1800hs hard cyclic hits. And nothing, virtually nothing coming out of the drive train at all.
I honestly lost count of how many I have built and flown. My vibe logging shows head vibes under an index of 2d during hard cyclic moves and full pitch hits. Basically showing a head rotating with no blades installed! Most other 700s show peaks hitting upwards of magnitude 12 to 16. And on the vibe logs, my tail doesn't exist! I have never ever seen that before, out of prob close to 5000 logs over in the Skookum Robotics section. Including my own. Holy snikes batman!

I do have the typical Kontronik up down can bounce though that is caused by harmonic magnetic field collapses most 12 stator and up motor cans suffer from. I need to play with my timing and pwm to see if I can remedy this also. But they are low enough to just live with.

Originally Posted by Raptorapture

Great to see you're back in the air with the Tri. Looks nice!

It just became my favorite flying heli, like maybe forever. Last week I would have been hard pressed to compare this to my high opinion of my Sab 800's flight character. Once I equipped my G800 with my Tri 800 NHPs, and cranked up my SK70s agility as far as possible, it simply came alive. Sab blades just suck!

Now my Triabolo 700, Dead silent in flight, and nimble. That nimbleness I didn't have with it in 800 gear. And seamless power. Great tail! Once I carried my Tri back from the pad, after my second pack while practicing invert funnels with it. I looked over at my Gob 700,, and said to myself, I can now see myself retiring that heli.

The big deal here is, the CF boom. It works brilliantly. Zero issues, no freak out in flight as Gerd had with whatever version he tried, and versions of fbl controllers. Causing him to ditch them and go the metal tube route. This boom just works!

[Raptorapture]

Really glad you're liking it. I've been debating whether to change my 700 to a Tri head. I really want to try out a Tri tail too.

Will be interesting to hear how you go without the boom supports. The stretch ones look cool!