SMALL - espritmodel.com SMALL - Telemetry SMALL - Radio
Reply
Thread Tools
Old Feb 16, 2010, 08:31 PM
Registered User
Joined Dec 2004
920 Posts
..

Quote:
Originally Posted by kuczy View Post
Well I live about 150mi south of of Don here in Ohio and I still have not been able to maiden mine or fly my wicked 4800 powered HL Skyblazer OR fly my HL 360D F16 yet. The snow here in Ohio has been relentless. We got like 8" yesterday and another 3" today on top of the 13" we got last week that hasn't melted yet and there is more on the way!! I think Friday is the only day in the 10 day forecast that doesn't have snow in it. If I'm lucky I might get mine out but, the there isn't a day in the foreseeable future with temps above 30F and if there has been a day with no snow then the wind has kicked up making the conditions terrible for flying these little jets! This has been the worst winter I can remember in my 32yrs.
ha!! well up here in the snowbelt (35mins East of Cleveland) I'm used to all this. Its really been actually slow up here with you guys hoggin' all that snow in the south. Its been a great year for the south snow resorts -- WV's Snowshoe and others.

Anyways -- I still have flown 2 out of every 3 weekends (or some days during week when off work) since the winter started. Conversely, this has been one of the BEST flying winters i can remember. Winds have been calm on days w/out snow. Other days i will fly in 15-20mph gusts with 1000g jet. Understandable that too much wind for these little guys

Mind you I am a desperate case for the air lately -- have put the F35 up in a fair amount of RAIN to the point where it was disappearing in the low-lying cloud/rain cover (and i was NOT high in the air at all) -- that day i lost radio with it and found it a ways away landed PERFECTLY on the hard pack snow upright -- i have NO idea how, i saw nothing and controlled less -- just stuffed with wet snow. Shake, Dry, Fly.

I've flown in snow -- its been a 'misty' and 'fine' type of snow alot this year, unlike the soft light fluffy squalls we are used to in the belt, from Lake Erie. Nonetheless in some light snowfall i have put both the F35 and EPO HK F16 up ---- power seems to fade out faster in these environments, about half the flight time -- although i recently had a problem with a bad soldier joint that i overlooked until the fan cut in mid air...

Anyways -- sorry to hijack Don. I fly 'em where i can get 'em. Fairly new to the EDF's yet -- by far the funnest types of ANYTHING r/c i've tried -- land, sea, or air -- i'm not a stranger to any. EDF's are where its at!!!
WRXronald is offline Find More Posts by WRXronald
Last edited by WRXronald; Feb 16, 2010 at 08:37 PM.
Reply With Quote
Sign up now
to remove ads between posts
Old Feb 16, 2010, 08:59 PM
Wonderfully Wicked
The Don's Avatar
Willoughby, Ohio
Joined Jan 2002
13,144 Posts
Quote:
Originally Posted by awayne View Post
Hey Don,
I have an extra micro fan and wicked 5400 sitting here. Is the rotor a direct fit on the 5400 shaft? Or did you need an adapter. If so, which one? I have the F-86 with a wemo micro and a Razor 300 in it right now. I'm getting about 150 watts @ 13amps wot and the security that it's not gonna blow up on me.
You need the 3mm adapter that Wemo sells. I bought my unit from Air Land and Sea with the 3mm adapter but you can get them separate.

http://www.airlandseahobby.com/shop_...m?subcat_ID=35
The Don is online now Find More Posts by The Don
RCG Plus Member
Old Feb 16, 2010, 09:06 PM
Registered User
awayne's Avatar
Pacifica,CA
Joined Oct 2006
323 Posts
Quote:
Originally Posted by The Don View Post
You need the 3mm adapter that Wemo sells. I bought my unit from Air Land and Sea with the 3mm adapter but you can get them separate.

http://www.airlandseahobby.com/shop_...m?subcat_ID=35
Great!

Thanks!
awayne is offline Find More Posts by awayne
Reply With Quote
Old Feb 16, 2010, 09:34 PM
Wonderfully Wicked
The Don's Avatar
Willoughby, Ohio
Joined Jan 2002
13,144 Posts
My main issue on cold flying is the lipos. Lipos can drop voltage under load in the cold and that is how I damaged my Alfa A-4 badly. I gave throttle and launched then 2 seconds later the LVC cut off and the model was not going fast enough to fly and crashed. You have to run the lipos to get them to warm up then they are OK. I use to fly in the winter and cold but not really anymore, I will fly down to about 32 if sunny out but there are other issue to watch for, like electronic (receivers) may not like the cold, some servos can gum up as the grease inside gets very thick and then you loose flight controls after launch.


Don
The Don is online now Find More Posts by The Don
RCG Plus Member
Old Feb 17, 2010, 06:46 AM
Registered User
Joined Dec 2004
920 Posts
Quote:
Originally Posted by The Don View Post
My main issue on cold flying is the lipos. Lipos can drop voltage under load in the cold and that is how I damaged my Alfa A-4 badly. I gave throttle and launched then 2 seconds later the LVC cut off and the model was not going fast enough to fly and crashed. You have to run the lipos to get them to warm up then they are OK. I use to fly in the winter and cold but not really anymore, I will fly down to about 32 if sunny out but there are other issue to watch for, like electronic (receivers) may not like the cold, some servos can gum up as the grease inside gets very thick and then you loose flight controls after launch.


Don

Its tricky in the cold no doubt. I've found down to about 22 degrees the lipo can hold out for about 1/2 as long as normally expected. (that's about the limit for my hands too, by the end of the flight and retrieving the jet out of the snow -- i usually can't feel my fingers.

That's with the lipo starting at about 65 degrees ambient temp in my home and small to average amount of ventilation for the battery in the model.

I don't use a low voltage cut, just time the lipo --- when it voltage drops due to cold, I land promptly
WRXronald is offline Find More Posts by WRXronald
Reply With Quote
Old Feb 17, 2010, 11:04 PM
Wonderfully Wicked
The Don's Avatar
Willoughby, Ohio
Joined Jan 2002
13,144 Posts
Here are the final photos I have on the AMX. I did not use the stock pushrods as they can bow and at higher speeds so that means no up elevator! I had no carbon tube to put over the pushrods so just used regular pushrod material. I also glued a 1" long piece of carbon on the trailing edges to lock the ailerons. The tailerons have plenty of movement so it will be just fine this way for controls. I also took a photo in the cockpit showing the lipo location which is forward in the nose. I had to modify the front of the canopy to get the tab to still fit. I used a piece of plywood as seen in the photo.
The Don is online now Find More Posts by The Don
RCG Plus Member
Old Feb 18, 2010, 09:08 AM
cmd
Registered User
cmd's Avatar
Niceville, FL
Joined Oct 2004
1,220 Posts
Don,

With the fan/motor, battery, pushrods, etc. What is the new All up weight?

I'm getting concerned with the reports of stock fan failures. It may be your set-up will be the way to go. Not sure I need all the Watts you are going to get. I think a sedate 200-250 would be fine for me.
cmd is offline Find More Posts by cmd
Reply With Quote
Old Feb 18, 2010, 09:33 AM
Registered User
Joined Dec 2004
920 Posts
..

Don now you've got me thinking... 4S 1000mah 30C's eh?


My Rhino 40C's 3s 1050's are back ordered and no sign in sight of coming in.

HobbyCity has the Turnigy 4s 1000 30C's for $1 LESS than the Rhino referenced, AND in stock.

You're really got me thinking of trying 4s. The weight difference between mentioned LIPOs is only 17grams. To net another 150 watts+ that is a worthwhile weight gain by far.

I hadn't considered prior, but if you can pull it off with a 4800kv... maybe I'll try the 5000kv motor i have and see what it does. I could always setup a 85 to 90% max throttle curve, but that would be inefficient use of the setup...

I have a 4s 1600mah 30C at home -- maybe I'll spin it up tonight and hope it doesn't go BANG in my HAND.
WRXronald is offline Find More Posts by WRXronald
Reply With Quote
Old Feb 18, 2010, 05:54 PM
Wonderfully Wicked
The Don's Avatar
Willoughby, Ohio
Joined Jan 2002
13,144 Posts
Quote:
Originally Posted by cmd View Post
Don,
With the fan/motor, battery, pushrods, etc. What is the new All up weight?
13.2ounces with 3S1300 lipo
The Don is online now Find More Posts by The Don
RCG Plus Member
Old Feb 18, 2010, 06:07 PM
Registered User
Joined Dec 2004
920 Posts
whelp i did it...

ran it up today on 4s 1600mah 30C.... 440watts, 31amps @ 75% throttle.

Its too hot i think... I don't want to distract Don's thread on Wicked mods -- so check the base 50mm Jpower thread if u have interest in more details
WRXronald is offline Find More Posts by WRXronald
Last edited by WRXronald; Feb 18, 2010 at 06:14 PM.
Reply With Quote
Old Feb 18, 2010, 07:59 PM
Wonderfully Wicked
The Don's Avatar
Willoughby, Ohio
Joined Jan 2002
13,144 Posts
Quick rule of thumb for you when going from 3S to 4S expect your new watts to be at least (4/3)^2= 1.78 times your 3S wattage. It is usually a little more but if more than 2 times then the motor is getting overloaded.

Looks like I can test fly Saturday!

Don
The Don is online now Find More Posts by The Don
RCG Plus Member
Old Feb 18, 2010, 08:15 PM
Registered User
Joined Dec 2004
920 Posts
Quote:
Originally Posted by The Don View Post
Quick rule of thumb for you when going from 3S to 4S expect your new watts to be at least (4/3)^2= 1.78 times your 3S wattage. It is usually a little more but if more than 2 times then the motor is getting overloaded.

Looks like I can test fly Saturday!

Don
ok thanks Don for that math. Looking at it then maybe i was alot closer to 100% throttle than I thought. I know at exactly 50% it put down 270watts. When i got up in that 380's range i kinda lost track of exactly where i was at with the stick as I was really concentrating on holding the fan (which felt like it wanted to rip right out of my hand at that point despite grippy gloves) -- For certain i was not at 100% throttle but maybe i was in the 90's and not 80's. Of course I assume your math compares Equally rated 3s to 4s lipo? Whereas here I took a 2100 3s 20C (42amps continuous) to a 1600 4s 30C (48amps continuous) -- close but not equal. The 4s 1000mah is considerably less capable -- 30amps continuous. So likely that amps will not exceed 400 on the smaller 4s lipo (not continuous anyways)

So Don, do you think the 4s 1000mah 30C's can handle that much wattage and current ? I know the rating says yes, but i rarely trust any of these lipos to perform as the sticker's indicate. I guess yes -- in the air the jet is moving so its not as downright TOUGH on a power system as 'on the bench'. Further, I doubt I'll ever need to plug out 100% throttle with that kinda power in such a tiny jet anyways.

I think i may try my luck and get the 4s 1000's instead.. $1 cheaper and in stock at HobbyKing; unlike the backordered Rhino 3s 40C's. I guess the power will be there if i went 4s to pretty much fly 50% throttle (or less) for 90% of the flight time. And 121grams compared to 103 grams. So the 4s is 17% heavier than the 3s --- but the watts are at LEAST 50% more (78% by your handy rule of thumb [some type of pun in there somewhere ], but remember the C ratings are different on the lipos being compared). The jet itself is only maybe 5% heavier AUW when considering the 17grams addt'l battery weight of 4s 30C 1000 compared to 3s 40C 1050. The math on that is a no brainer if the motor can handle it. We know the fan can. Thinking of this fan at 650watts is somethin' else -- even with pretty decent ear protection this thing SCREAMS at 440w

Saturday does look nice for flying with 5-10mph wind forecasted for my area. I flew one tonight on the FW F35 when i got home, a bit windy -- but still a nice evening for it -- fubar the landing and now its back to a little hot glue gun -- i hate those full flying elevators on the F35 dangit

Anxious for your flight report Don!!!
WRXronald is offline Find More Posts by WRXronald
Last edited by WRXronald; Feb 18, 2010 at 09:09 PM.
Reply With Quote
Old Feb 18, 2010, 08:26 PM
Wonderfully Wicked
The Don's Avatar
Willoughby, Ohio
Joined Jan 2002
13,144 Posts
Most ESCs reach full throttle about 75% of stick travel unless you have a programable ESC that you set the ESC endpoints. I plan on trying the 4S1000 30C based on what I tested the 4800 to. I do not plan on being WOT all the time anyhow.

When going to different lipos in the same fan, you can do the rough math, from 3S to 5S expect (5/3)^2= 2.77 times and 4S down to 3S is (3/4)^2= .563

Don
The Don is online now Find More Posts by The Don
RCG Plus Member
Old Feb 18, 2010, 09:18 PM
Registered User
Joined Dec 2004
920 Posts
..

ok -- good stuff to know - thanks!


Any guesses as to how much thrust?


WRXronald is offline Find More Posts by WRXronald
Reply With Quote
Old Feb 18, 2010, 10:05 PM
Wonderfully Wicked
The Don's Avatar
Willoughby, Ohio
Joined Jan 2002
13,144 Posts
If you know thrust at one wattage level you can predict thrust at another wattage level with the same fan and motor. Say you have 16 ounces at 300 watts then at 500 watts you will have (500/300)^.6666 so 1.405 times the thrust.
The Don is online now Find More Posts by The Don
RCG Plus Member
Reply


Thread Tools

Similar Threads
Category Thread Thread Starter Forum Replies Last Post
Discussion JPower P-38 (Sold By Banana Hobby) fred_n Electric Warbirds 6352 Yesterday 03:44 PM
Article Hobby Lobby JPower AMX Light Attack Jet ARF Review Bajora Foamy EDFs 394 Jul 12, 2013 02:49 PM
Build Log Wicked Powered Jpower F5-E The Don Don's RC 53 Feb 20, 2010 08:30 PM
Video Hobby Lobby's JPower AMX EDF with a Hoffman Magnetics Mightey Mite 60mm Motor Bajora Electric Plane Talk 2 Jan 06, 2009 06:48 PM