Topic: D80 build thread

Thought id make a start

How do you know he hasn't "built" it?......

Andy.........

How do you know he hasn't "built" it?......

Andy.........

cause he aint got it yet

Good start  Great Rx, using same model in both Opii and so far totally glitch free despite full carbon fuz. It should have an even easier time in the D80 - its kevlar isnt it?

Does this mean Adam is ahead in the race to be first in the air with a D80?

Will be fascinating to see how they perform back-to-back with the MCTs out there.
My gut-feeling is there won't be a big margin at less than about 225 mph.
Anyone else got a hunch, just for fun?

Lets see how that aerofoil works at less than 200

Any one want another of those recievers I have one that only been installed in a model for a good price.

Any one want another of those recievers I have one that only been installed in a model for a good price.

YEP! I'll take it J
George

SOld

Lets see how that aerofoil works at less than 200

Have no fear Andy, itll be perfect. I think Joe shot his load on the slow speed handeling a bit prematurely... 

So most of the bits will be in the box.
Receiver ordered, and now thinking of power.
Been thinking of using a 2 cell lipo or 8 cell transmitter pack and connecting it to a regulator, But how many amps will it be pulling? need some sparki nerds to comment.

[....Been thinking of using a 2 cell lipo or 8 cell transmitter pack and connecting it to a regulator, But how many amps will it be pulling? need some sparki nerds to comment.]

Will, why not ask Joe what battery he's been using with those nice hefty servos?
Then just match or better it.

FWIW I'm intending to use high capacity sub-C 9.6V eneloops & regulate to 5.9V with the MCT, albeit (necessarily) with less juicy servos.

I don't get this 9.6v thing. Seems pointless. You'll either have a linear bec getting seriously hot or a switching bec making plenty of noise.

As for the rx - damn - I've only got the 9ch single conversion! Crystal and everything - oldskool LOL.

Joe just had a 5cell 2000 eneloop in there, but they're nice and warm out there... I'm going for a 2s lipo with one of these  SAFETY-SWITCH LiPo  - Punctilio Modelspot Ltd

Switch, checker, regulator all in one. Have used the Powerbox version before - very nice, and seems to work well. Mpx version is better in that it has dual outlets into the rx and a more hefty connector to the battery as stock. Made by the same people, just the mpx one has slightly higher spec re connectors.

Z

I don't get this 9.6v thing. Seems pointless. You'll either have a linear bec getting seriously hot or a switching bec making plenty of noise.

As for the rx - damn - I've only got the 9ch single conversion! Crystal and everything - oldskool LOL.

Joe just had a 5cell 2000 eneloop in there, but they're nice and warm out there... I'm going for a 2s lipo with one of these  SAFETY-SWITCH LiPo  - Punctilio Modelspot Ltd

Switch, checker, regulator all in one. Have used the Powerbox version before - very nice, and seems to work well. Mpx version is better in that it has dual outlets into the rx and a more hefty connector to the battery as stock. Made by the same people, just the mpx one has slightly higher spec re connectors.

Z

Looks good to me mate, I may do the same. George

I don't get this 9.6v thing. Seems pointless. You'll either have a linear bec getting seriously hot or a switching bec making plenty of noise.

As for the rx - damn - I've only got the 9ch single conversion! Crystal and everything - oldskool LOL.

Joe just had a 5cell 2000 eneloop in there, but they're nice and warm out there... I'm going for a 2s lipo with one of these  SAFETY-SWITCH LiPo  - Punctilio Modelspot Ltd

Switch, checker, regulator all in one. Have used the Powerbox version before - very nice, and seems to work well. Mpx version is better in that it has dual outlets into the rx and a more hefty connector to the battery as stock. Made by the same people, just the mpx one has slightly higher spec re connectors.

Z

Dude that is only going to give youa continuous current of 2 amp and a max of 5amp

I have been looking at others that go upto higher amp's on ebay.

The cold is my main concern, but also having the correct size pack to last a day but not too long.
I was also thinking of using a tx pac enloop. But they have such small wires.
Part Of me is thinking 5 cell sub c enloops will be the best option. And from my understanding enloops manager the cold quite well.

Got a while to think about it all.

Will

8A External UBEC w/ 5.1V Step-Down Voltage Regulator on eBay (end time  10-Jan-10 12:54:55 GMT)

Link to 8 to 15 amp regulator

But That is why the question, how many amps do we need for these animals. Is it something we will only really know when we het them and test the servos? Where is that sparki nerd.

what about A cells. Bigger and badder than aa. Much higher dischare available. Depends on the fus of course. Eneloops and other instants are only available in aa or aaa.

I have good results using lipo+regulator in the cold.  Better than NiMH for sure.  Maybe partly because the lipo is so understressed - you're asking a battery that can deliver say 40A to deliver say 3A.  Can hardly fail can it? 

You need a trustworthy regulator though.  That MPX one looks superb, except for the current being too low.  You could use two.  I'm using a 3A (5A peak) regulator with six analog servos (in the Erwin) no problem.  But for six beefy digi servos you'd need more.  The ones I've found totally good and reliable are the HobbyWing BECs from giant cod.  I use the 3A one in all my gliders.  It runs totally cold and generates no interference on 35MHz or 2.4.  But I reckon one of the bigger ones would be a good choice in more demanding setups.  (Don't choose the other brands on that website, it has to be HobbyWing).

Hobbywing  5-7.5A UBEC for Lipoly

Will - Adam has had one of those in a model with 5 big digis and one regular servo - plenty of back torque from big power model aerobatic surfaces. I've had mine on a somewhat larger model, but with smaller surfaces - that ran 4 standard servos and 2 225mgs, with no problem.

Consider what 2A and 5A means. 2A means that each servo could be pulling 400ma constantly, and 5A means that they will be pulling 1A each! With the careful linkage design etc on these, I am sure that will be enough.

If they were pulling 2A continuous, Joe's D80 would be in bits by now. Last time out it DSed at over 300 for over half an hour apparently. If it was pulling 2A plus the entire time, the battery would have been flat, completely flat, in an hour. If it had any spikes of 5A towards the end of that, I'm pretty sure it would have started wigging out on voltage. So based on that highly non-empircal and anti-scientific analysis   (yeah yeah I know you'll still call me a nerd LOL) I reckon that the MPX switch is perfect. My only worry is performance at low temperature. And if you stick in a 2100mah 2s lipo in there or similar with 20C capability i.e. 42A, then I'm confident that even in really cold weather, getting up to 5A out of that battery will be no problem.

Anyway, no right way, no wrong way. Incidentially, one of the things I quite like about lipos is that when they are knackered, they usually give you a visual clue i.e. swelling or whatever.

Z

Have no fear Andy, itll be perfect. I think Joe shot his load on the slow speed handeling a bit prematurely... 

Aint that the truth! As long as you never ever EVER give it reflex it will fly great. It fly's perfect!
I flew it for 20+ mins @300mph and then passed it to a friend who flew it for 20 mins then he gave it to another friend who flew it for 15 mins all 250+ the whole time. I checked my 5 cell eneloop battery the next day and it still had 90 percent capacity left in it. Eneloop batteries are the best! I dont know about cold weather though. It gets down to freezing for short periods here but I dont remember ever having problems because of it. Maybe I just didnt subject the model to the cold for long enough.

Im looking forward to this build. The models will ship on Monday. It is a beast of a box!

Nice one Joe!
Your not kidding on the beast of a box... 61 lbs of it!

So eneloops are good to go guys???

George

personally I would just use a good 4 cell pack, perhaps 2/3 AA .

Interlect 1600 will give loads of power. 30A ish

If I was able I'd use sub C's,  again as a 4 cell pack.

Tried and trusted. Kiss.

How many hours do you fly for when you Ds? -- a lot less than when you sports fly..

How big do those servos need to be? -- It's down to linkages and throws more than anything else.

Mike Why only 4 cell?

Did anyone notice the 5 hitec 7955TG going in the for sale section £250, £50 / servo.

And i think most people will agree Zim is an RC Areo nerd, after all he thinks "Chicks Dig Aero moddlers.

What about these cells
2 Camlink 4000mAh C Eneloop Type Rechargeable Batteries on eBay (end time  24-Dec-09 12:33:35 GMT)

Joe, What is the diameter of the D80 Fuz ±.

Will

[..Your not kidding on the beast of a box... 61 lbs of it!]

Great idea to ship some extra lead ballast


Not shifting yet from my preliminary choice of regulated 9.6V eneloops; but (our electric friends) what is the state of play with the latest Lipos?

Seems not long ago slopers were shying away from the new battery technology for safety reasons: recall risk of explosion during charging & risk of fire during hard landings/crashes.
Not the sort of thing I'd like to have lying around the house or workshop.......
And Zim just indicated that they may swell physically when approaching life's end (a favourable characteristic? yikes!).

The D80 fuses are about 3" dia. Can fit just about any battery pack. Personally, I would stay away from 4 cell packs. They sacrifice lots of speed and torque. 5 cell is a must for my builds. Eneloop batteries are amazing. Try some and see what I mean.

Im still undecided, but if i do go for a lipo then ill be fitting one of these bad boys

Fast Lad Performance

   5volt 5amp supply to the rx and a whopping 100 amp peak/ 10amp continous supply to the servos, at either 5volt or 6 volt the decision is yours, built in switch or you can use the supplied remote switch,

  So you could stall all your servos but your rx will still be getting a nice 5volt supply at all times

I did point Zim to these but seems he has brushed them to one side for some reason,

oh yeah and built in battery meter

  seems they work well in Helis so no reason for us not to get on with them

Does look a good alternative Ads

Why expose electronic boxes to damp wet misserable uk weather when there is no need to. except to satisfy your need to think you have done something better. If there is a minute advantage to having a controlled voltage - then its lost in the disadvantage of all the extra complexity, and our climate.

+1

Add to that hard landings, High G-forces, more connectors etc... Adding complexity (in series) isnt going to improve reliability, only make it worse. At least that 10A system looks to be properly spec'd - a 2amp BEC in a 5-servo DS plane where servo loads increase with speed (as a square of?) seems way too marginal for my liking.

Adam:

That's a seriously large & expensive piece of kit!
I'm looking to obtain a modest over-capacity as a safety margin, particularly during cold weather; but isn't this over-engineering?
Your choice

My Opus V has a crude though so far fully effective solution (installed by a previous owner) of 5 cell AA Nimh powering RX plus 6 x HS85 analogues at a nominal "6 volts". Of course, the actual voltage delivered at any moment will vary hugely, dependent on battery charge state & load demand.
But it works well enough & the servos certainly benefit from the extra voltage.

Just looking for a less crude & hopefully even more effective installation in the MCT, with quality RX plus 5 x digitals.
Figure a large capacity 9.6V eneloop will be more than adequate to ensure the regulator can deliver a nice, stable 5.9/6V to the loads even during short periods of relatively high demand. Mostly, demand will be low - little more than operating the RX & Ttail servo.
I need to check I can get eneloops in sub-C, just for the sake of reduced internal resistence, but otherwise AAs will surely suffice.

Mine's a layman's approach. Advice from anyone with expertise will be greatly appreciated.

I think the servo load could be high though. And get higher the faster you go. Even if the wing control surfaces are not moving, the servo still has to hold position against aerodynamic loads + weight of surface * G force component (whatever that is)...

LOL did anyone actually read Joe's post? 2000mah Eneloop battery DSing for well over an hour at speeds higher than our national record. With capacity to spare. Simple maths tells us that with Joe's set-up, which we are mirroring, and Joe's linkages, which we are using, and Joe's horn's, which we are also using, and therefore Joe's geometry, an hour's worth of DSing will use considerably less than 2000mah. Which means that the system is pulling down considerably less than 2A constant. In fact, Joe implies well under 1A constant.

Adam - the reason why I have brushed aside that regulator system is due to my completely facked memory  - completely forgot it!! Now that I remember it, yeah, that's an ace piece of kit. I loikes it. Same sort of money as my suggestion, and it leaves the two I have for the other two homes that I already had earmarked them for.

Lipo is nice because they aren't fussy about the kind of discharge that Mike refers to. Also Graham - it's winter! Flammable batteries can only be a benefit!

Joe - yeah we use the Eneloops in our F3F ships. Also very happy with them - seem to be OK in cold too - will let you know after tomorrow's sub-zero outing!!

Z

Oh and Aeronaut mate - I'd take those Hobbywing things with a pinch of salt mate. What's the point in rating it 7.5A when the wire that's supposed to be carrying that will probably not manage to carry 7.5A for any length of time anyway? Doesn't look correctly specced to me mate.

Z

I highly reccomend using a 5 cell Eneloop pack for your D80. The servos are not even close to seeing thier max working load and dont pull much current at all. If you, for example, used a smaller servo it would actually use more battery as it would draw more current trying to do it's job. The Hitec 7955TG servos just sit there and laugh at the loads on this plane. They also remain very tight and they will probably survive any crash you have. The servos are overkill but I use them because they have the best geartrain on the market. For those of you who havent used them before, your in for a treat. They are smooth and have excellent centering. They are also quiet. If the gear install is done exactly like my build thread your surfaces will be completly slop free, rock solid. The elevator servo does have a small amount of gear lash but it is still the best setup so far and I have no doubt that it will be good to 400+.

Joe, we like our servo's NOISEY so that we can hear em going 'eeeeeewwwwwweeeeewwww' on the way by! 

George

ps we are just waiting again for Zim and WIll to go DSing in minus 1 or 2 degrees.... 

We must be MAD!

Those servos sound amazing.  (Big heavy servo though.  But presumably no problem in the D80, it's wings must be not so thin.)   I see Phoenixmp sells them for £59.95 - new at £60 might be a better option than second-hand at £50.

2/3A

With a fuse that size, the A-123 betteries seem a natural way to go - no regualtor needed either .  The only thing that's holding me back with them is the exceedingly flat discharge curve, which makes it difficult to judge when the battery is nearing the need for a recharge .

I would agree that I wouldn't be comfortable with 2 amps..

As I only have 3 cell LiPos lying around, the MPX unit would not suit me either.

I'm converting a few bigger gliders to LiPo, and have ordered the Turnigy 8 - 15 Amp reg., which seems very similar to the ones posted above.

Now, what's the craic with ENELOOPS ?  This side of the pond (+Joe), most seem to think theyr'e the answer to global warming and world peace, but there are many threads and blogs over the other side that warn against their high internal resistance, which leads to low current delivery ?  I wish I knew the full story.  The problem is that there are so many ways of doing things, and most of them work most of the time.  This tends to "mask" problem areas, and the occasional crash usually remains unexplained ..  As an example, I've been running an 8 servo glider (flaps and spoilers) on an "Instant" 4 cell pack.  No problems to date,  but after reading and thinking about it more, I started breaking out in a cold sweat.  Tests with a voltmeter showed a huge draw when deploying brakes..  So, I'm coverting the Lipo's, at least I know that capacity/current issues are not going to be a problem.

"The problem is that there are so many ways of doing things, and most of them work most of the time.  This tends to "mask" problem areas"

Aint that the truth.  One day one of my regulators will fail and I'll have a crash.  But so far I've had 100% reliability whereas my friends' NMh packs seem to fail more often.  I think it's due to using old NMh packs that haven't been charged recently.  Whereas an old lipo that hasn't been charged recently is still totally fine!  Lipos have such big 'headway' (they have such high capacity and such high amperage delivery ability) that even if they're 80% knackered and only 30% charged, they still work fine. 

But I can completely understand anyone who prefers to avoid regulators, since they are theoretically an extra potential failure point.

you could just use sub c in your volcano Chris. Can't go wrong.

I didnt mention A123 as most people do not have chargers for them and are so unfamiliar with them that it is useless most of the time to suggest using them. They are my favorite battery and I use them in my D160. You can practicaly weld with them and charge them in a flash. Those are truly the best batteries I have ever used but for smaller gliders I have been using Eneloop. I have used A123 in an Opus and some earlier D80's and they are great. I dont like having to use a balancing tap all the time. I really feel they are not necessary in a D80 but if I didnt use Eneloop I would use A123.
 From my experience, the shortened lifespan from running higher voltage to servos has never been clear as my servos dont last that long. I have run 7.5 regulated volts into servos for 6 months using them for about 20 hrs a week and never had any problems. This was done on over ten servos for a project at work. For Dsing, I only fly for maybe an hour max on any given model in a day. If I want to fly more than that I have a charger with me.

just sayin what works for me,5x3150,9.6v tranny pack  instants /eneloop,s 3amp reg supplyin 5.1 volts constant...jobs a good un,didn,t want all that lead in the nose so i put batteries instead..works trouble free and would fly till i was dizzy on that!