RE: Phase 3 EF - 16  
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RE: Phase 3 EF - 16 - 9/2/2008 5:53:19 AM   
whissel_blowa


 

Posts: 300
Joined: 3/23/2006
From: , , AUSTRALIA
Status: online 		The exhaust duct should be trimmed to the length of the tailcone, once ducts go over 6 inches long they really should not taper at all until the last 2 inches or so of pipe. Even under 6 inches the most correct nozzle is straight out from the fan then tapering down 10% of the fans swept area. Have a look at this pic of my current F16 on the bench, the exhaust is a genuine wemotec part that fits the back of the fan like a glove!

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RE: Phase 3 EF - 16 - 9/2/2008 10:51:03 AM   
Aussie Damo



Posts: 127
Joined: 6/24/2004
From: GeelongVictoria, AUSTRALIA
Status: offline 		just a little thing on converging nozzles, if u make the exhaust area smaller you get a higher specific thrust output (eg you will go faster) but your thrust effeciency will go do (ie more energy is needed to create same thrust)

main point, wana go fast make nozzle converge, wanna fly longer leave it as big as possible

cheers

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RE: Phase 3 EF - 16 - 9/2/2008 12:14:06 PM   
whissel_blowa


 

Posts: 300
Joined: 3/23/2006
From: , , AUSTRALIA
Status: online 		It doesnt quite work that way, all fans require a reduction in outlet diameter in order to maximise their efficiency. Going past the sweet spot in outlet size will raise your eflux speed a certain degree but will lose you sometimes considerable thrust.
If the outlet is over the FSA of the fan you will experience a reduction in thrust in flight, we have proven this with the large 90mm mirage, stock exhaust is oversize at around 95mm and the model suffers from less than 1:1 thrust to weight and a good but not great performance. Bringing the nozzle down to the correct 78mm sees a big increase in thrust as well as eflux velocity "in the air" and the model picks up almost 20mph in speed and climbs much stronger.

As for amp draw, I have recorded minimal changes between a bench tested fan with no exhaust duct at all and the same fan inside a model with ducts varying from 4-6 inches long to 15+ inches long (all with the correct outlet size or within a mm of it). Its only when you go seriously past the optimum nozzle diameter that your amp draw rises noticeably. Graph below shows our 90mm F86 Sabre in flight, pulling 49A constant with a 16 inch almost straight duct. On the bench the same fan pulled the exact same figures with open back.

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< Message edited by extreme_rc -- 9/2/2008 12:22:37 PM >

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       Post #: 53

RE: Phase 3 EF - 16 - 9/2/2008 11:52:31 PM   
skrez


 

Posts: 361
Joined: 6/17/2004
From: Mokena, IL, USA
Status: offline 		Hi Guys,
I don`t like the color decals that comes with the kit so I want to repaint it. Where can I buy decals for this scale size plane?Regards,
Frank

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       Post #: 54

RE: Phase 3 EF - 16 - 9/3/2008 1:34:35 AM   
MerlinFan


 

Posts: 98
Joined: 4/15/2005
From: , CA, USA
Status: offline 		You just have to shop around some to find decals. I was lucky to score an Ultrafly F16 that I am robbing the Thunderbirds decals from and giving the plane to my grandson to build with a brushed pusher prop setup. I see you are from IL. Slot and Wing in Champaign has the biggest decal and sticker collection I've ever seen.
On a similar subject, as I remember, water based spraypaint used to be easy to find, however I can't find it anywhere now. I have heard about Krylon H2O but nobody around here carries it. Does anybody know...........

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       Post #: 55

RE: Phase 3 EF - 16 - 9/20/2008 3:46:10 AM   
dinoatwoodys


 

Posts: 1
Joined: 9/12/2006
From: palmetto, FL, USA
Status: offline 		michaels crafts carries the h2o paints

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RE: Phase 3 EF - 16 - 10/11/2008 1:21:24 AM   
crashcrash


 

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From: St Louis, MI, USA
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quote:

ORIGINAL: dinoatwoodys

michaels crafts carries the h2o paints


I print my own and use quality packing tape to affix. My first F-16 crashed too, but I think it was a BAD servo that got me. I bought the bare bones from hobby people, and re-installed the original fan unit and replaced the bad servo...the new one flies fine. I did READ the ESC's are becomming a problem in burning up. I use a 2200mAh 20C, I keep the flights to 7-8 minuets, no probs so far (knock on wood).

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RE: Phase 3 EF - 16 - 10/11/2008 1:23:50 AM   
crashcrash


 

Posts: 4003
Joined: 11/23/2006
From: St Louis, MI, USA
Status: offline 		Use MS paint to increase or decrease size, print and cut it out...they're OK from 10ft and out.

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RE: Phase 3 EF - 16 - 10/13/2008 3:50:01 AM   
gooseF22


 

Posts: 705
Joined: 8/12/2006
From: Fort Wayne, IN, USA
Status: offline 		I saw one fly the other day with an upgraded 40 amp controller and the stock fan on a evo lite 2500 4S. then he flew it on a 2500 3S. he flew pretty hard on 3s and it did pretty good about 70mph or so. With the 4S, the thing was ballistic and fast, but he limited his full throttle to 10 seconds and then let it cool. It is the most impressive foamie I have seen. A bunch of us jet guys saw it and we all ordered one the next day.

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RE: Phase 3 EF - 16 - 10/13/2008 4:21:03 AM   
crashcrash


 

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quote:

ORIGINAL: gooseF22

I saw one fly the other day with an upgraded 40 amp controller and the stock fan on a evo lite 2500 4S. then he flew it on a 2500 3S. he flew pretty hard on 3s and it did pretty good about 70mph or so. With the 4S, the thing was ballistic and fast, but he limited his full throttle to 10 seconds and then let it cool. It is the most impressive foamie I have seen. A bunch of us jet guys saw it and we all ordered one the next day.


I've flown mine 5-6 times now....I'm finally getting used to it. Even as stock....it'll eat up 500yds QUICK.

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RE: Phase 3 EF - 16 - 10/17/2008 10:13:31 PM   
crashcrash


 

Posts: 4003
Joined: 11/23/2006
From: St Louis, MI, USA
Status: offline 		Been flying mine almost every day when wind permits. Can't say enough good about it. The supposed prob with the ESC.....I haven't even had mine to offer to get warm while running 2200mAh 20C's. I run it full power on takeoff, and run it normally a little below half throttle which would get me 15-20 minuets per flight, but I don't keep it up longer than 10 minuets. I got the servo throws at 45% and expo dialed down to make it fly more stable and less quick reactions. At full speed at 100% throw...this would be a monster to fly. My first one crashed because of a bad servo....all the guts were good so I transferred it to a bare bones, added new servos....been flying my butt off since. This is a very impressive foamie.

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RE: Phase 3 EF - 16 - 10/18/2008 7:25:36 PM   
gooseF22


 

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From: Fort Wayne, IN, USA
Status: offline 		Hey guys, I have a 30 amp ESC that is good for 4S out of my wrecked Trojan. Do you think that will handle the stock motor on a 4S 2500? I will take it easy on it of course, just dont want to smoke it.

assembling it now

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RE: Phase 3 EF - 16 - 10/18/2008 9:25:15 PM   
crashcrash


 

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quote:

ORIGINAL: gooseF22

Hey guys, I have a 30 amp ESC that is good for 4S out of my wrecked Trojan. Do you think that will handle the stock motor on a 4S 2500? I will take it easy on it of course, just dont want to smoke it.

assembling it now


Ooooooohhhhhh....I'd be careful

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RE: Phase 3 EF - 16 - 10/19/2008 12:59:40 AM   
Squirrlybird


 

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From: Greenville, SC, USA
Status: offline 		http://donsrc.com/cart/index.php?act=viewProd&productId=52

If you want 4s, the motor above is a good choice on this (XF) fan. It is also a good 3s motor as well. This seems to be a common motor that wont break the bank. Just dont run the stock esc on it.

Some people are also using the little screamer motor from HL, but it is pretty pricey.

Every report that I have heard of using the stock motor on 4s shows that it will burn out fairly quickly.

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RE: Phase 3 EF - 16 - 10/19/2008 1:25:05 AM   
crashcrash


 

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quote:

ORIGINAL: Squirrlybird

http://donsrc.com/cart/index.php?act=viewProd&productId=52

If you want 4s, the motor above is a good choice on this (XF) fan. It is also a good 3s motor as well. This seems to be a common motor that wont break the bank. Just dont run the stock esc on it.

Some people are also using the little screamer motor from HL, but it is pretty pricey.

Every report that I have heard of using the stock motor on 4s shows that it will burn out fairly quickly.


I agree. AFter the stock one I got is done being battle tested (I'm having a ball with it), I may opt for a more powerful fan unit having more blades. Had a MINOR mishap tonight. I come into a slow turn at about 4ft up, I seen the nose drop (knew I had a stall going on), I gunned it, but it wasn't enough to pull it out. It impacted nose and right wing tip causing a slight bend in the right wing, popped the air intake plastic loose, and the right side of the lower fuse come loose as well. Had it repaired and flying in 20 minuets with no problems.

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RE: Phase 3 EF - 16 - 10/20/2008 2:06:54 AM   
gooseF22


 

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Joined: 8/12/2006
From: Fort Wayne, IN, USA
Status: offline 		OK guys,

Im going to order Dons wicked extreme and run my stock fan. I have a dualsky 40 amp ESC on the way. I want to run both 3S 2200's and 4S 2500 EVO LItes. They are the 20C 2500's.

I dont know what wicked extreme option to order. One says standoff alone fits XF, and another says XF/Eflite.

Can you tell me which one to get?

For those running the bigger batts, I know to mount the motor aft, where did your battery end up. Do I have room to stuff a little spektrum receiver at the back of the