S-DIabolo Maintenance

[TommyBear]

John,

Was the servo gear the cause of the tumble?

Lynh

[Mercuriell]

Originally Posted by TommyBear

John,

Was the servo gear the cause of the tumble?

Lynh

Nope ground oscillation - most likely me being too casual with straightening blades before spool up

[firemedic295]

I almost had the same thing happened to me two days ago. It is really scary.

[Raptorapture]

Originally Posted by firemedic295

I almost had the same thing happened to me two days ago. It is really scary.

Your colour scheme is too nice! From above it reminds me of Avatar

[wblombard]

Mmmm seems Ed is afraid to post some pictures....Come on Ed, show us what you got. It looks good!!!

[Mercuriell]

Finally got her back in the air this afternoon after an age of squatting on the dining room table! (the heli - not me)

Noted a few hollows in the fuze as mentioned previously and didn't think a lot of it - with the bird belly up on the table I 'sighted' along the fuze keel and there was no doubt it was bent !!

RIpped off the tail and was really surprised to see a significant ding and bend in the boom! Now I have no recollection of a significant tail ditch so am not at all sure how long I have had it or whether it had anything to do with the head wobble I was chasing or the twitch tail servo - the pushrod was certainly binding in the guides !

Lesson is that tail fuze can hide a multitude of sins and needs a higher alertness than with pod and boom and if you have significant dents in your fairing - check the boom!



Second surprise after a perfect test flight was that I was polishing up the blades with some furniture polish when I felt some roughness under one blade - although the top was perfect underneath there was a significant crack in the blade undersurface signifying a decent bend and fracture of the insides - needless to say it has gone and been replaced with my spare set of X-Blades - now I have a single X-Blade to make up a threesome sometime





Another benefit of having the fuze off was able to perfectly straighten the landing gear and make them symmetrical - almost impossible with them mounted on the heli - the wire although very heavy gauge is soft and easily bendable by hand.

[Mercuriell]

Another thing came to mind looking at the SD on the bench - just as Jan is making a training TDR2 - you could easily make a training SD by having just the front canopy - thus you get the low drag landing gear, tough gear train and head for those higher eye-watering HS ! - How about it Gerd !!!

[firemedic295]

John I would like to see that to. If we can get a canopy like the S to fit on a Diablo it would be great.

[tgiencke]

Originally Posted by Mercuriell

Second surprise after a perfect test flight was that I was polishing up the blades with some furniture polish when I felt some roughness under one blade - although the top was perfect underneath there was a significant crack in the blade undersurface signifying a decent bend and fracture of the insides - needless to say it has gone and been replaced with my spare set of X-Blades - now I have a single X-Blade to make up a threesome sometime

Any idea how the blade got cracked?

[Mercuriell]

Originally Posted by tgiencke

Any idea how the blade got cracked?

Pretty sure that was the tumble on spool up, stripped a servo and broke a link so likely dug turf with it. It's the bent boom that has me puzzled.

[wblombard]

John, could this not have been due to your motor pinion shut down episode, I recollect you stating that you were surprised how strong the fuse is for taking that his. Cant believe you only spotted this now...wondering how many flights you did like this...

Any pictures of the fuse? Does it show any fatigue in that area?

Hope you get her up in the air soon.

[Mercuriell]

She's back in the air as of this afternoon the motor pinion episode was on the maiden, since then I clicked 233 at the Aussie speed cup, can't believe I did that with a bent boom! The fuze looks fine now, I have had a head wobble at low revs for the last 3-4 flights so I guess it happened then!

[JRAY]

Wow, John! Glad you found those. How noticeable was the fuselage before pulling it?

[Mercuriell]

Originally Posted by JRAY

Wow, John! Glad you found those. How noticeable was the fuselage before pulling it?

The dents were noticeable but not gross, thought they were hangar rash from cuddling up to the SF2 on the back seat of the utility, actually tried to push them out using a blade pushed inside the fuze and a hot air gun, with some success!

[JRAY]

Yep, I used a heat gun and a towel to take some of my heat warping out. Any chance its just from light 3D or anything? I try not to give any quick tail inputs since the fuse just can't offer the level of support that the boom supports do. I imagine that it wouldn't take much 3D to bend a boom.

[Mercuriell]

I just dunno Jason, I use the SD for speed runs only, no autos, no 3D so I guess an occult tail dig must be the most likely, time will tell. Flew her on some Rails this afternoon, very sweet and very fast ....

[craigdieselmac]

My first few flights with my S were very eventful and hardly flights at all. They are not stable on the ground without the fuse on.. That paired with a faulty brand new vbar sensor made for some interesting test runs. My first spool up she fought me like evry gyro axis was backwards.. Tip tests showed the swash moving correctly, and flight control checks were normal.. Spool up and it was almost uncontrollable. I changed the sensor and it worked like a charm. Only after a boom strike and ruining the set of DH711's that came with her. I put my rails on though and have not looked back.. Flies like a dream when she is in the air.. Initial spool ups still make me nervous but I spend a lot more time Ming sure the blades are centered than I have on any other helicopter I have, or even currently own

[Mercuriell]

I wouldn't trust my top shelf helis to vbar, had at least 2 bad sensors No doubt these Hugh stressed helis are intolerant of any weak links in the chain. The Rails are very good, not quite up to the Speed-X but better value.

[JRAY]

Originally Posted by Mercuriell

I just dunno Jason, I use the SD for speed runs only, no autos, no 3D so I guess an occult tail dig must be the most likely, time will tell. Flew her on some Rails this afternoon, very sweet and very fast ....

John, what do you think about the Rails compared to the DH's? I fly the Rails on my TDR and love them, but really like the DH's on the S. I've thought about swapping them to compare, but I also want a set of X Blades for the S and/or TDR. I tried a set of Helix, and IMHO, not so good for speed. Good blades, cool shape, but they seemed twitchy and agile, just not locked in like the Rails.





As far as spool up on the S, to be honest, I've had no issue. No wobble, nothing. I've got the Kosmik on a 15 second spool up, and move to zero pitch on spool up. I've barely ever gotten one shake. Now, I probably just doomed myself, lol.

[Mercuriell]

I think my spool up shake and tail twichy servo was the bent boom. The S flies very sweetly and seems to have no vices aerodynamically. I am quite sure it is faster than the Banshee.

I found the DH 696 pitchy on the SF2, 711s better. The Rails come in a close 2nd but the Speed X are tops for stability at uber high HS IMHO. Wish they were cheaper.