Maudib

My Feedback: (51)

For me the 4 cell lion packs provide internal redundancy (essentially two 2-cell packs wired in parallel)

They offer higher voltage and always supply a full 6 volts (or 5.6 or whatever your regulator is set for) and that means consistent power & speed from my servos at all times.

I don't want to start with a 4.8 pack that drops below 4.8 volts and slowly gets worse over the flight.

6 volt (5 cell) nimh/nicad packs are better, but still not as consitent as lion. They then do become heavier and not as much capacity...
The newest lion packs are 4800 mah (2S2P 2400's)and are the same weight as before... trr 2 2400 mah pcks and see how much they weigh...

Lion loses so little charge when not in use it's not worth measuring, but nimh/nicads will lsoe enough to require you to charge them before heading to the field again. More charges reduces life.

Pricing? here are 3 scenarios:
______________________________
Two of the 4.8 volt 1650 AA packs weigh a total of 8.2 oz and they list are $22.95 each or about $46... two standard HD switches weigh 1.5 oz and are $15 each

TOTAL COST: $76 for 4.8 volts, 3300 mah and you have to charge two batteries not one (you'll need another triton at the field or wait for tw to charge)
TOTAL WEIGHT:9.7 oz
______________________________
Two of the 6.0 volt 1650 AA packs weigh a total of 10.1 oz and they list are $24.95 each or about $50... two standard HD switches weigh 1.5 oz and are $15 each

TOTAL COST: $80 for 6.0 volts, 3300 mah and you have to charge two batteries not one (you'll need another triton at the field or wait for tw to charge)
TOTAL WEIGHT:11.7 oz
_______________________________


A Fromeco 4800 mah pack weighs 6.6 oz and costs $54 and a Smart-Fly 6 volt regulator with FailSafe Switch weighs .5 oz and costs $45.

Total cost: $99 for full-time regulated 4800 mah and failsafe switch
TOTAL WEIGHT: 7.1 oz.

I make my own 4 cell 4800 mah packs and they cost me $33... a total of $78 for the setup.


So a Lion setup costs very little more... not hundreds...

Now on the ignition... you could easily go with a 4.8 volt NiMH and save about $50... but I still prefer the longer runtime of a 2400 mah pack and not having to charge it before I go to the field if it has set since last week.


On the reciever it IS lighter, more capacity, more convenient in installation of a single pack vs. 2 packs and 2 switches and offers a slightly greater redundancy.

flat spin

In my experience the longevity of Lipo's is much better as well so any extra you may spend is soon made up there anyway. I like em. You would be amazed at how few people run them here in the Uk though, you can hardly even get regulators.

Maudib

My Feedback: (51)

I've had more success with charging them too... no false peaking on new packs.

Hey Flatspin... you should corner the UK market and become a Fromeco and Smart-Fly reseller... (I get 1% for the idea)

flat spin

Well great minds and all that. I am awaitnig my first shipment from Smartfly next week. Great products and the guy who runs it Robert is a gentlemen.

Yak Man

My Feedback: (1)

Planning to go with 6 volt - 2100 mah Nimh on the ignition, No regulator. DA -50
2 ea. 6 volt - 2700 mah Nimh on RX, No regulators.
3 Heavy Duty Cermark Switches with Charge Jack.
One RX -JR 945S Dual Conversion. Plug Additional RX Battery into any extra channel.
JR -8611 5 Ea. JR 4131 Throttle.
2 packs = Reduncance on The RX.
Keep it Simple.
Use Sirius Charger at the field if I'm lucky enough to get in enough flights to recharge.

Same Battery set up as H-9 Sukhoi w/ DA- 100 but running Dual 8611's on Rudder & Elevator & Aileron.

Rx & Ignition packs from Radical RC

This is my setup and is only intended for my personal amusement. I have a DP Edge with regulators on 6 volts and I can't notice any advantage w/ regulators, just additional cost and another point of failure.

What is the tracking # on the boat?

jrjohn

My Feedback: (24)

Dave, I think the whole thing really hinges on weather or not you will exhaust your batterys in a normal day of flying.

as far as the fail safe switch. Get a load of this. I already had one fail and it rusulted in a crash. How can that be??? One of the wires to the switch broke at the solder joint, that ment NO POWER! So in a sense no switch is completly fail safe if the incoming, or outgoing power wire breaks where it's conected to the switch or the reciever. I'll never run one switch again! Failsafe.... BS! \\

The same goes for the reduntant battery, now I'm not an expert but I'm guessing that there is only one lead wire coming off that battery and going to your reciever, so the same applies. If a wire or solder joint breaks, your coming down post haste. (maybe I'm wrong and they run 2 wires, and they plug into seperate channels of your reciever. if so I'm wrong.... sorry in advanve.)

BTW I had this happen to me too, the stinking solder joint broke on the battery. If you really want a redundant system, you need two of everything seperate from each other. Thats the way it's done in General aviation. One last thought, If I was going with lipo's and regualtors, I'd also want two recievers. If one of your regualtors fails and lets too many volts through it will burn out your reciever. That will ruin anybodys day.

John

Aerosplat

My Feedback: (12)

Sorry for taking so long to post the tank pictures. I have been sick (Head cold and sore throat). I am better today, but I am still at home from work. The Medicine makes me very drowsy.
Installing the tank on the CG---
In these pictures you will see I made two platforms to sit the tank on. I used 1/4 balsa (picked a very light sheet). The two boxes together did not even register on my digital scale (resolution to .2 oz). the front box needs to be about 1/8 shorter than the rear because of the plywood doubler on the floor in the front. The tops are level when installed. I used 1/4 balsa to make a tank stop on the back box to keep the tank from sliding back. You need to have this area more narrow than the box to allow clearance for the wing bolt to go in. I shortened the wing bolts to 1 inch. That still gives enough thread to go completely through the blind nut in the wing. Anything longer is wasted. The rear box is about 1/8 inch behind the wing tube. I epoxied the front box to the lite ply, and used CA to attach the rear box to the balsa top of the pipe tunnel. I epoxied Velcro to the sides of the boxes to secure the tank. The very front strap keeps the tank from sliding forward. You can see from the side picture, the tank is about 3/8 inch above the side of the fuselage, but the Blue front portion of the canopy covers this when installed. The bottom of the tank is about 1/4 inch above the wing tube when the foam padding is installed. The tops of the boxes are about 1/8 inch above the wing tube.
Measurements:
Front box - 2 3/4 wide, 2 1/2 front to back, and 1 1/4 high. It is resting against the plywood former just in front of the wing tube.
Rear box - 2 3/4 wide, 1 3/4 from to back, and 1 3/8 high.
The tank stop is 4 pieces of 1/4 balsa. The front two are flush with the top of the box, and the rear two extend 1 inch above the platform. They are 1 3/4 wide. The very rear tank stop is 1inch wide. I would say the total weight addition over the stock tank setup is less than an ounce, because you still have to have Velcro or something to secure the tank in the normal configuration.

TailTouch

My Feedback: (54)

LOL

jrjohn

My Feedback: (24)

Dave, I'm not trying to bash anybodys idea's. Everybody is right under certain circumstances, as long as nothing goes wrong. I've experienced the failsafe illusion.

I'm just trying to make one thing perfectly clear. the term "failsafe" is a very spacific term in most cases. For instance. The failsafe switch your using is a "failsafe switch" only the switch function (on and off) is fail safe. So in reality it's a failsafe switch with a regulator. It doen't have a failsafe regulator! The switch itself is made so it's always on, and only turned off mechanicaly. If the mechanical function of the switch fails, it fails "ON" What happens if the regulator fails??? does it reroute the power to a secondary regulator? Can the power stop completly? or does it let 7.2 volts through? I'm guessing it's the last two. What happens if a solder joint on the switch fails? The result is no power again. You can't have true redundancy if parts of your system use common componants. Ie regulator, wiring, ect.... For this reason, one battery that has redundant cells but uses a common wire is not fully redundant (disclaimer... if there are two power leads then I'm wrong) And a failsafe switch that uses common leads and a regulator that is not failsafe is also not a redundant system and is subject to failure as well. You would actually need two switches and regulators powered by to seperate batteries to have a redundant power system. BUT... even in this senario if a regulator fails and lets 7.2 volts through, you just fried your reciever! Don't be fooled by the word "failsafe" it's only refering to a small portion of the electrical system, the mechanical switch itself and thats all. Redundancy is the only way to be sure you won't have a loss of power.

Last example (I promise) I have a JR PCM transmiter and reciever. On the day of my crash I had all servo's programed with a failsafe to a predetermined position if there was a loss of signal. All servo's were to go neutral, and engine to idle. When the failsafe switch lead failed it shut down my electrical system, My failsafe servo's were useless because there was no power to carry out the command. My engine stayed at full throttle. (it wasn't pretty)

John

flatlandmike

My Feedback: (17)

i choose the big li-on in my 50 cc because i hate to charge and i can get 25 to 30 flights over Fri sat and Sunday no extra charging this is what i love and I'm not adding any extra weight to get it
most of the time i don't need to unpack the plane when I'm going flying next day


Hello my name is Mike and I'm lazy

Aerosplat

My Feedback: (12)

Choke setup:
I mounted a bell-crank to a piece of hardwood 3/4 x 3/4 by 1/2 inch thick. I epoxied this to the Lite plywood with just enough clearance for the throttle linkage. I had to slightly enlarge the opening in the firewall to allow clearance for the choke linkage. I tapped the choke lever for a 4-40 and mounted a ball link. 4-40 rod is screwed into the ball link, and a soldered on clevis is on the end at the bell-crank. Going out of the fuselage I used a Sullivan golden clevis with a 4-40 rod inserted into Nyrod inner tube. I passed the Nyrod outer tubing through the lite ply side, foam and balsa sheeting to exit just behind the edge of the cowl. I used a 4-40 rod on the outside, and bent it so it is almost flush with the fuselage when the choke is off. Pull and choke is on, push and choke is off.

flatlandmike

My Feedback: (17)

jrjohn some short term 8 volts to your rx isnt a death nail i have seen that given to a 955 from jr rx accidently of course for like 15 minutes and every thing turned out ok

jrjohn

My Feedback: (24)

Mike, thats good to know. But how would you know if your regulator failed. Everything would work great until it fried. (3 flights later)

John

flatlandmike

My Feedback: (17)

i quess there would be no way to know if it was passing the current . i surely hope it doesnt happend to any one.

Aerosplat

My Feedback: (12)

Just my two cents on Failsafe and regulators.
I am using SmartFly regulators with failsafe. The actual regulator on/off switch is built into the regulator, and is electrical (solid state), not mechanical. The external switch you use to turn the power on/off is a mechanical switch. However, when the external switch is in the off position, the switch is actually "ON", that is to say the contacts in the switch are closed. This short circuit signals the solid state switch in the regulator to turn the regulator off. That is why the regulator draws a very small amount of current when it is switched off, and SmartFly recommends you disconnect the battery when the regulator will be left off for several days. That way you won't drain your battery.
The "Failsafe" works this way -- If the switch or any part of the wiring going to the switch fails, it will cause an open circuit. The switch is already in an open circuit condition when the regulator is powered on, so nothing changes. Only problem now is you can't cut the regulator off with the mechanical switch, you have to unplug the battery. I have tested this by unplugging the leads to the switch when the regulator was powered on. It continued to supply power. Also, I once plugged the battery to the regulator with the switch unplugged, the regulator immediately powered up! The only way the mechanical switch could turn the regulator off would be to fail in a short circuit condition, and this is HIGHLY unlikely.

All things Electronic have a failure point, most of them have a single point of failure. What if a capacitor, resistor, or IC chip in you receiver failed? - no amount of redundancy would save you. You just have to choose the level of backup you are comfortable with, and go with that. It is after all, an individual choice, no laws or regulations apply here.

jrjohn

My Feedback: (24)

Mike as long as I don't use that system I'm sure everybody will be fine. I'm like the myth buster and proving ground for Newtons law

john

P. s Just out of curosity how did somebody run 9 volts through a reciever?

flatlandmike

My Feedback: (17)

8 volts li-ion was almost fully charged and unregulated

jrjohn

My Feedback: (24)

Aero, I totally agree with you about the "switch" part of the electrical system being failsafe. It's the regulator, wiring ect that worries me, only because I've seen it happen. Again, I'm only trying to point out that "failsafe switch" only refers to one small portion of the system, not the regulator. Redundancy is the only way to be totally failsafe. And yes if the reciever shorts, your screwed too. Thats why some guys use redundant reciever systems. and exactly why I wouldn't add anymore weak links to an non-redundant electrical system.

John

Enough for me

jrjohn

My Feedback: (24)

Why can't the OEM's make a reciever that runs from 4.8 to 9 volts. We can put a man on the moon, and make Cher look like shes only 35 yrs old but we can't make a reciever that handles 9 volts? Heck... my shaver will handle anywhere from 110 to 220. Maybe Victor Kiam (Remington shavers Pres.) should help out.

where the hell is that Boat!!

John

ptgarcia

My Feedback: (36)

I don't buy in to this so-called "redundancy" ideology. Unless you have two of everything (right down to the transmitter) you don't have a redundant system, and that just isn't going to happen. Just like everything else in life, sometimes we put the fate of our planes into other peoples hands. There's just no getting around that. I just make sure the components I select are the "cream of the crop". And I always use a single receiver, single battery, and a single switch on my planes (33% and smaller)...always. I know someday it may happen, but to this day I have never lost a plane to anything but my own dumb thumbs.

Oh yeah, the Yak looks like a mighty fine aircraft. I think its time to start saving my lunch money again...

I just thought I would add that I only use Fromeco.org Li-Ion's for the receiver and I use a small NiMH from Radical R/C for the ignition...not that anyone cares .

Maudib

My Feedback: (51)

John,

I certainly apprciate your opinion and you make very vaild points... only... it's a matter of of personal preference in addition to confidence level.

I'm confident that quality electronics offer such a low failure rate that they are not an issue "to me".

A switch, I believe is the largest culprit of failures followed by battery failure... a dead cell or being undercharged.

When it comes to redundancy, I have to agree with ptgarcia... you can't duplicate everything... and I don't even try...

What I do attempt to do is eliminate the 2 worst risks and in the process, lighten my plane and add favorable benefits.

I just trust a solid state failsafe switch/regulator. I also trust lions. I'm not worried about redundancy

My point is that lions are not "hundreds" more expensive liek the BS that the noBS site is claiming... maybe $25-$50 at most... they offer the advantage of longer flying time, lighter weight and consistent power/speed of the servos. I have flown as much as 6-7 flights on my DV in a day... and I wrung the crap out of it. And each and everytime I checked the voltage with my meter and never even had to think about charging.

I charge the plane when I get home and don't worry about charging again the night before or morning of flying.

With nihms/nicads I would get false peaks and spent too much time"topping them off" at the field.

Since the vast majority of battery failures are due to bad cells... a single lion pack offers a small amount of redundancy that if a cell goes bads, a pair is still providing juice.

I guess what I am trying to say is that one isn't better than the other safetywise... I just prefer lighter packs, consitent power to the servos, longer flight times and the solid state switch.

And with that I'm done talking about lions.

Want to debate the benefits of a fiber optic ignition kill switch?

jrjohn

My Feedback: (24)

David, I agree with everything you say. Now where's that dam boat! I don't know anything about fiber optics. except when I was younger I worked on a crew putting in underground telephone cable. we were told if we ever cut a fiber optics cable that we might as well shut the machine off and leave it, cause the telephone company now owned it.

John

Maudib

My Feedback: (51)

They own everything else why not the machine too... They told you to leave it because if you stayed... they'd own you too.... Just throw a logo on you and make you an installer.

coche

My Feedback: (4)

well.....

I have my DA-50, 2.5" standoffs, stock muffler..
hitec servos, SWB servo arms, unihub from airwild to mount the ruder set up...
twisted servo extensions from airwild, smart-fly regulators and switches, fromeco bateries...
4" tru-turn ultimate menz cut spinner with lightened back plate, 23x8 mejslik prop
my futaba reciver... I even have the name of EF YAK on the radio memory....

I cant remember what else is missing... [sm=surprised.gif]

ummmmm [sm=idea.gif] ohhhhhhh yessssss I am missing the yak!! [:@]

I gues I have to seat and wait for that boat to arrive!

ScaleRules

My Feedback: (5)

Aerosplat,

Is that the stock tank that comes from EF or did you up/down size? What capacity is it anyways?

I have my deposit in ... wonder what number in line i am? Hmmmm!