Lynx stretch kit and servos

[gtruk]

Is anyone running stock servos with the stretch kit? If so, is everything working fine for you? I've had a weird thing happen twice now. I flew four flights with stock servos last weekend and everything was fine. I went out to fly on Friday and after takeoff noticed I had the right roll. I was like uh oh, vibe issue. So I landed, reset and the right servo immediately dropped down even without anything spinning up. so it can't be a vibe issue. I took the servo apart and noticed that one of the gears was stripped, so I rebuilt everything, reset the FBL and pitch settings and everything was perfect on the bench. I go out to fly today and first battery goes without a hitch but the second battery, when taking off, does the same thing again. So I'm wondering if the stock servos can't handle the longer blades or something. I did get this weird shake when it was spinning down, as in the whole bird started to dance but I'm not sure if it was from the servo or something else is off causing it to dance like that. Blades are balanced and and pitch settings are all spot on, so don't think it's a balance issue.

Anyone experience anything like this and do you think just moving to new servos will solve this?

[SumOFparts]

I would not run stock servos on a stretch - they aint that good to begin with.
The only reason I continue to use them is my blades costs like $3 pair - but even that door is shutting soon....getting tired of replacing elevator servos on slightest mishap - their economy factor is evaporating....


MKS Servo DS92A+
are the best you can get IMHO -

http://www.helidirect.com/mks-servo-ds92a-p-26532.hdx


Tail servo is real pricey -

http://www.helidirect.com/mks-ds95i-...vo-p-23315.hdx


Its hard to find a cyclic set for resale - tend to be keepers....
The tail ones I see all the time - but think its the cyclic ones almost dont have an equal...
If you catch them when heli direct has coupon - you can get em for under 40 w/free ship..

[gtruk]

I appreciate the tip but I'm looking for answers at the moment. Are the longer Lynx blades causing the stock servo gears to strip / fail? Why is the servo dropping down when powered up?

[Lu523]

I had the same problem with the Spektrum servos. Just sitting on the bench the longer blades will make the servos move. Changed to KST servos and no problems.

[gtruk]

Originally Posted by Lu523

I had the same problem with the Spektrum servos. Just sitting on the bench the longer blades will make the servos move. Changed to KST servos and no problems.

I did a quick test in the living room tonight only spinning it up part way, with the blades on, hit TH and as it was slowing down it did a chicken dance and it looked like the right servo arm was being forced down while doing the dance and causing it to skip a gear. I'm not sure what's causing it to dance like that. The blades are tracking perfectly. I checked the blade balance again tonight and adjusted it with a small piece of tape. Other than that, there are no visible vibrations during spin up so not sure what's causing the dance unless it's simply the servo cannot handle the force of the rotational weight.

What KST servos?

I'm already running a Hitec tail servo which has been rock solid. I have an Align 45-50A ESC, are there any servos that I can run where I won't need to add an external BEC?

[Nelsonisms]

Sometimes servos just go bad and then all kinds of weird random shit starts happening. It's odd that they would strip that easy though. We all know that the stock servos are weak, but I didn't think they were that weak. I definitely wouldn't trust them.

I'm still running mine on the internal BEC (3A continuous/5A peak) in a Castle ESC (Edge Lite 50) with KST DS215MG on cyclic and MKS DS95i on the tail (6V). I can do continuous tic-tocs and full collective punchouts from a dive with the stretch installed without brownouts. So I personally don't see any reason to install an external BEC. The internal BEC can certainly handle the load. The only reason might be for some peace of mind and redundancy. But on the 450 with limited space, I'll take simplicity and reduced wiring over redundancy. I just don't know the specs for the BEC in the Align ESC. If it's got similar specs to the Castle then I think you could probably get away with it. I would definitely bench test the hell out of it first though.

[gtruk]

Thanks again Nelsonisms! I actually went ahead and ordered a set of KST's last night bast on reviews and specs compared to a few others. It's crazy though, when spinning down the whole bird starts to shake and getting as close as I dared, I heard the servo arm get forced down and basically jumped a tooth inside. If I took the arm off and recentered it, everything moved as expected but something in the shake was really pressing on the right servo pretty darn hard. I'm going to do some bench tests today to try figuring out what's going on.

[SumOFparts]

If stock servos are out of their comfort zone - most likely the stock dampers are too..........

Probably gonna need heavier pitch links too - mini size tail servo......

[Nelsonisms]

Originally Posted by SumOFparts

If stock servos are out of their comfort zone - most likely the stock dampers are too..........
.

Definitely use Lynx ultra dampeners with the stretch kit. Don't know about the pitch links. I'm using the Lynx turnbuckles, but I figure the stock ones would still work just as well.

Originally Posted by SumOFparts

Probably gonna need heavier pitch links too - mini size tail servo......

Like I said, no problems with a DS95i which is a micro servo, albeit a powerful and fast one. I've heard of people using the KST DS215MG on the tail as well, but I've not tried that myself.

[Lu523]

The KST works good on the tail.

[KiloXray]

I ran a TGY 306 (same as the KST) for a while on my warp with no issue. Would recommend as a budget servo.

[Nelsonisms]

The last of my Align servos finally gave up the ghost this past weekend. It was the tail servo on my 300X...a DS425M tail servo. The thing burned out while it was just sitting on the table. Screw those things, but I digress... I think I'll try out a spare TGY-306G-HV I have laying around based on what you guys are saying.

[gtruk]

For what it's worth, I've been using the Hitec tail servo for dozens of flights and it's been rock solid.

Ok, so I think I figured out the problem. The machined swash from Blade has tons of slop in it. I mean, my original swash of nearly two years has less slop than this thing. What a piece! The main shaft had a tiny bend as well from the crazy chicken dance it would do when spinning down. It was imperceptible to the eye, but I could hear it when rolling it across a marble counter. I put in a new shaft and the old swash and everything looks much better and perfectly smooth. I'll have to wait until tomorrow to test it with the blades on since it's to loud with the kids in bed. ;-) Anyway, I don't know if amain will warranty it since I've had it since Mar and am just installing it. Here's a little video I made showing the amount of slop. [ame]http://youtu.be/OXevIERdpFk[/ame]

[KiloXray]

Originally Posted by Nelsonisms

The last of my Align servos finally gave up the ghost this past weekend. It was the tail servo on my 300X...a DS425M tail servo. The thing burned out while it was just sitting on the table. Screw those things, but I digress... I think I'll try out a spare TGY-306G-HV I have laying around based on what you guys are saying.

Don't get me wrong, Nelson. I can really feel the difference between the 306 and a 95i. When i say "recommend" I am saying that I am confident in the durability and that it will work. If you are trying to save some coin it is a good option.

[Nelsonisms]

Originally Posted by KiloXray

Don't get me wrong, Nelson. I can really feel the difference between the 306 and a 95i. When i say "recommend" I am saying that I am confident in the durability and that it will work. If you are trying to save some coin it is a good option.

Yeah I get you. I'm not too worried about it on the 300X and would like to try it just for a frame of reference. I figure if that piece of junk Align servo worked then the 306G-HV should as well and I just happen to have a spare laying around to try. Plus I'll be able to crank up the voltage to 7.2V since the cyclics are the same servos. If I decide to keep it long term I'll probably invest in another DS95i tail servo because they are that good. I'm just still on the fence whether I want to spend any more money on that heli or just sell it.

[Nelsonisms]

Originally Posted by gtruk

Ok, so I think I figured out the problem. The machined swash from Blade has tons of slop in it. I mean, my original swash of nearly two years has less slop than this thing. What a piece! The main shaft had a tiny bend as well from the crazy chicken dance it would do when spinning down. It was imperceptible to the eye, but I could hear it when rolling it across a marble counter. I put in a new shaft and the old swash and everything looks much better and perfectly smooth. I'll have to wait until tomorrow to test it with the blades on since it's to loud with the kids in bed. ;-) Anyway, I don't know if amain will warranty it since I've had it since Mar and am just installing it. Here's a little video I made showing the amount of slop. http://youtu.be/OXevIERdpFk

I've had pretty much the same experience with all of HH/Blade's "hop up" aluminum parts. They are all really poor quality compared to the competition which is ridiculous for the price. I had the Blade aluminum swash for a while and had to scrap it after about a month of use because the anti-rotation pin just cracked off out of the blue without any crashes.

Shoot, even the one they used in the picture on HH's site looks like it's been through the ringer. LOL...couldn't they find one with no wear for the photoshoot? They probably pulled this one off of James Haley's heli right before this was shot.



I'm not a huge Microheli fan, but I do have the Microheli swash on my 450X and it's been solid for a long time. I suppose Lynx will release one eventually.

The difference in quality is apparent even between these two photos...

[heliwreck]

i noticed my smaller helis will do a chicken dance when the blades are slowing down or speeding up if one of the bolts holding a blade is a little tighter than the other. I think the looser blade tip will move forward a little when spooling down causing an imbalance or lag behind a little when spooling up. Try to tighten them up the same as close as you can.

[gtruk]

That's hilarious, on the photo shoot. I was looking at their site this morning to see if there were any other options and noticed the same thing in the picture as well. It looks full of plastic bits just like you said, straight off someone's heli. I'd like to get a new swash as my original has tons of flights on it, just not sure if I should get the stock or try the micro-heli. To bad they don't have the same quality of a Gaui! ;-)

Heliwreck, I was thinking the same thing last night when I was testing and played around with tightening and loosening the blades but still got the same funky chicken. I'm gona test again tonight but think the sloppy swash was the culprit.

It looks like Lynx has their new swash plate out now, but doesn't look to be for sale yet.
http://www.lynxheli.com/product_info...ducts_id=24039

[Nelsonisms]

Yep, once again Lynx proves they're the shit when it comes to this stuff. Not only is it a beautiful part, but they improved the design with the 90 degree opposed balls. It kinda looks like a miniature Gaui formula swash. I might not be able to resist getting one right away...but I'll try.

[KiloXray]

Other than looking bad ass, what do you suppose the actual benefit is of a ball layout like that?

I'm pretty impressed with the fact that it is rebuildable by the user. That is a super cool feature that not many swashes have. Super cool.

Kinda bums me out that I am about to sell my 450X.