Vibe 50 eelctrics suggestions?

[TonyUK]

Hi guys, Just received my Vibe 50 today. Im going to be running the jr 8900g tail and the 8915 cyclics. I wanted to stick with the align 2 in 1 like I have on my 600, but was just worried about voltage, as I think the cyclics and tail run off 4.8. It looks like the align 2 in 1 gives out 5.8v using a 7.4 2 cell lipo so im a little worried about blowing something. I just thought some of you could suggest maybe an alternative 2 in 1?

Thanks very much for any help.

Anthony

[Pinecone]

1) The DS8915 is the same as the DS8717, and the DS8717 is rated for 6 volts (5 celll pack) and there are more than a few people running them at 8.4 volts (2S lipo direct).

2) The big problem is they can draw over 2 amps EACH. The Align 2 in 1 supplies a max of 6 amps, so right there you have maxed out your supply, not inculding the Rx, throttle servo, gyro and tail servo. I have a 2 in 1, as I had picked it up to use on a my 50 nitro when I got it, but since I am putting 8717s in it, I will not do so. I am thinking SGP ReactorX with the ability tor un the cyclic at 6 or 6.8 volts and the RX and the others at 5.2 volts.

[Stricker22]

I agree with Pinecone on this, I run a Reactor X on my vibe at 6.8V and it runs flawless. It is also rated at 15 continuous amps and has some redundency protection built in. Also you wont need to run drop downs to your gyro and tail.

Easy to setup, so far very happy with it.

[Pinecone]

Only thing with the Reactor X, is I would like a bit more head room on my Rx, and would like to run the throttle at 6 volts or so. But 5.2 isn't bad.

So I am also thinking about the AR7100 with 10A Spektrum Regulator. But then only 6 volts to cyclic servos.

[torch628]

Pinecone,

I'm fairly new to rx lipo packs, high speed digital servos, and regulators. Right now I've just got a 4.8V, 2300mAh NiMh rx pack running DS 821 servos.

When you say you'd like more head room on your reciever what exactly are you referring to? I was reading the specs for the SGP Reactor X and it claims over 15 amps draw while the regulator you're talking about shows 10amps. I also see a lot of guys on the other site seem to be a fan of the Arizona regulator which depending on load seems to have an upper limit of 18 amps (if I'm reading the graph correctly). I assumed when I read your post that by more headroom you meant a higher amp draw ceiling but after reading the specs I thought maybe I misunderstood you.

I'm just looking for a CLEAN and SIMPLE setup when I do decide to upgrade.

As a side note....I saw a guy on the other site giving a dude a hard time for using a DS821 servo on his Vibe because "from all he's heard...he'd never be able to trust it". We'll I just crashed my Vibe the other day because of a locked up DS 821 but figured I may not have had the push pull links set up quite right thus causing the servo to bind....(in other words my fault) but now I'm not so sure. Anyone here have any thoughts on that?

Thanks for the help

Matt

[Pinecone]

The DS821 is NOT rated for 50 size nitro helicopters. From Spektrum site:

New Guidelines for DS821 Servo Use
Tuesday, February 20, 2007

The DS821 servo is a powerful, accurate sport digital servo recommended for RC airplane applications up to 1.20-size. For helicopters, the DS821 operates best with 30-size glow models, and up to 50-size electric. Loads and vibration in larger models may cause premature failure of the servo resulting in damage or injury to property and persons.

Important: Do not use liquid thread lock with the DS821 servo!

Do not use any form of liquid thread lock to secure the servo arm screw to the output shaft of the DS821 servo. Chemicals in these liquids react with the polycarbonate gear set causing the plastic to become brittle, fracturing the final output gear.

On to the power situation. When I mean headroom, I mean a bit higher voltage to keep the voltage up under hard use to prevent low voltage brownouts. I would prefer to run the Rx at 6 volts, with a regulator for 5.2 to the tail. But 5.2 is fine.

I would NOT run a Spektrum system in a heli with a 4 cell pack.

[torch628]

Pinecone,

Thanks for the tips. I had, some time ago, read the specs for the DS821 but the reference to 50 size "electric only" must have gotten past me.

Looks like I'll be clearing out some room in the budget.

Matt

[Pinecone]

Clear a LOT of room. The servos you WANT are the JR DS8717s. You can find them for just under $100 each, normal price is $110 each. :( But AMAZING servos.

But out of stock most places until near the end of the month. :(

BTW, Scott Gray ReactorX is on its way to me for my Vibe. :)

So my setup will be:

JR R921 Rx
3 x JR DS8717 cyclic servos
JR 770 3D with 8900G tgyro and tail servo
SGP Reactor X for power
Aerospire MultiGov Pro - gov and mixture
JR DS3517 for the Throttle

I don't know what I will run for the mixture. I read that Finless is running an HS65 on the Trex700, so I might go that way. Others are running HS55s. I also have a set of HS45s and a set of DS285s that could all be used.

I thought of using a DS285 for throttle.

[torch628]

Pinecone,

Thanks again for help and advice. I looked last night and like you said 8717s are out everywhere. After all I've read the SGP Reactor X seems to be the way to go.

Looks like I've got some ground time coming my way. (Good time to work some extra to pay for this)

Matt

[Pinecone]

Luckily I found a set of 8717 NIP over on RR. Should be shipped today. I will have one spare I can sell if that will help (seller had 4 and would only sell complete package). And I know where at least one other was for sale online. :)

But I have HEARD, that 8717s might ship next week. But Horizon says late July, and they seem to seldom beat their predictions.

[EBCooper]

Wow Pinecone, that is the exact setup I'm putting on my second Vibe 50. Thats assuming I can wait long enough for a set of 8717's.

[sparky]

If you can, change to 8715! Same servo, but red alumnium case that also acts as a heatsink! Look better and a little more ruged!

[Pinecone]

Huh? 8717s have the red Al case. And JR doesn't list an 8715 servo. OK, 8715 is non-US market of the same servo. Except that the 8715 isn't rated at 6 volts, where as the 8717 is rated to be used at 6 volts.

And 8717s are back in stock at places. Ron's HeliProz South had them last week.

[sparky]

Over here, we get 8917 and 8915. Both Identical in every aspect except the 8917 is plastic case. The 8917 is the asian market 8717. And yes, both are rated above 6 volts.

[Pinecone]

The the 8917 ISN'T the same as the 8717, the 8717 has the red aluminum case.

[lgbman]

Clear a LOT of room. The servos you WANT are the JR DS8717s. You can find them for just under $100 each, normal price is $110 each. :( But AMAZING servos.

But out of stock most places until near the end of the month. :(

BTW, Scott Gray ReactorX is on its way to me for my Vibe. :)

So my setup will be:

JR R921 Rx
3 x JR DS8717 cyclic servos
JR 770 3D with 8900G tgyro and tail servo
SGP Reactor X for power
Aerospire MultiGov Pro - gov and mixture
JR DS3517 for the Throttle

I don't know what I will run for the mixture. I read that Finless is running an HS65 on the Trex700, so I might go that way. Others are running HS55s. I also have a set of HS45s and a set of DS285s that could all be used.

I thought of using a DS285 for throttle.

Pincone ... DS3517 ? No listing at JR ... What is transit time of that one ? Why not another 8717 on throttle ?

[Pinecone]

Here:

http://www.jrradios.com/Products/Default.aspx?ProdID=JRPS3517

Or here:

http://www.readyheli.com/DS3517_High_Speed_Mini_Servo_p/jrps3517.htm

.11 on 4.8 volts.

[lgbman]

Ahhh , was'nt looking under the mini servo section . Is that to cut down weight due to the vibe being on the slightly heavy side of 50 class helis ? Looking at the vibe more now than ever thanks to all the feed back from you guys . Was about to get a 600N .

[Pinecone]

Also just space. No need for a huge servo on the throttle. I would even consider a micro for the throttle. :)

[spike5150]

Anyone consider the JR 890G "Sport" Tail Servo instead of 8900G? I am not doing any 3D and am collecting parts for a Vibe 50 to build over he winter.

Would an 890G work for throttle?

This will be my first nitro. I saw a Vibe 50 at the field this weekend and like it compared to getting another T-REX (already have 450 and 500). Not that theres' anything wrong with them - just want to change it up and all reports are good on the Vibe.

Do I need a Governor to get in the air for sport flying?

Thanks - hopefully we can get more Vibe 50's in fellow Freaks hangars!

Jeremy

[Pinecone]

You could use the 890G, if you really need to save money. But the tail servo is pretty important.

For throttle, just use a Hitec HS-81. Cheap, fast, and light.

You don't need a gov, in fact you don't want to use one for break in. But I have a MultiGov Pro on mine, which gives me both gov and mixture control.

But DO get some gov magnets and install them as you build the heli. MUCH easier to do then, than to wait till later.

This kit builds extremely well. A couple of tips:

Make SURE you have the left frame on the left and the right on the right. Some people have had to take everything apart and do it over.

I managed to get all three bearing blocks upside down. So watch this, to ME the diagram looks wrong, but do it by where the bearing flange is supposed to be.

Do NOT over tighten the lower Jesus bolt. A couple of guys ahve locked up their one way doing this. I may even consider replacing the one way sleeve as I have over tightened mine.

The servo install order is wrong in the manual. The lower servo of the two rearmost needs to be installed first.

[spike5150]

Thanks Terry - I appreciate he info. Makes sense to use a small servo on throttle - not much torqe needed, just speed. Looking forward to getting the kit and building. I really enjoy that part.

[sparky]

Carefull! Too much speed is just as bad as not enough on the throttle! If the servo works faster than the engine can respond, problems will occur!

[Pinecone]

Agreed, but so far, I haven't heard of that happening, and people are running 8717s, 8900Gs, and S9254s on the throttle.

I guess waht saves us, is that when you are working the motor hard and fast, the throttle is only running in the 50 - 100 range, and maybe even not time for it to get back to 50 in many cases.

[theLane]

Hey all, back to the original question here, I have a similar question. With the following components:

8700G tail servo
G7000T gyro
Align 2 in 1 w/2S Lipo
R921 rx

Do I need to use a step-down to the tail servo and gyro, just the tail servo or none at all?


Thanks in advance,
theLame