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Mini F-16 vintage project consideration

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Mini F-16 vintage project consideration

Old 01-05-2014, 08:30 AM
  #276  
MJD
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I agree, it sounds a lot like the power is not being used efficiently enough.
Old 01-19-2014, 05:52 PM
  #277  
Steve Westphal
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Rick......I have had thoughts along those same lines. Would you please post some pics of it?
Old 01-19-2014, 05:59 PM
  #278  
Steve Westphal
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Jaspur X.....where is my 140 bucks or the new Cox .020 and parts. It has been over a year since I mailed you a money order for $140.00 and I haven't heard from you since I noticed that you cashed the money order immediately. I am retired and money is hard to come by. I would like an answer to [email protected].

Steve Westphal
Old 01-19-2014, 09:00 PM
  #279  
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I have a feeling he is in the slammer.
Old 01-19-2014, 10:30 PM
  #280  
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Is he related to Malcolm X...?+
Old 01-20-2014, 04:46 PM
  #281  
Steve Westphal
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I hope he has a good reason for his complete lack of integrity. I should have seen a red flag when he told me that didn't use paypal. I hope to let everyone know that he is a scammer of the first order. I know a state patrolman in his area and have half a notion to send him over for a visit. I know that I am not the only person who has had trouble with him. One of our boards distinguished contributors got taken for 350 bucks by Jaspur X. Does anyone of our contributors live in his area? Please contact me at [email protected] I would love to chat with you. You know that if his scammings total over $1000.00 it is grand larceny. Please contact me if you have been scammed by this guy.

Steve W
Old 01-20-2014, 05:40 PM
  #282  
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I do not want to make a joke out of this, but flying 1/2A is a low budget deal [comparatively speaking] and this forum has had at least 3 "Low Budget" scammers in our midst during the past 10 years or so. [Tim Wiltse, Prole [self proclaimed "proletariat"] & Jaspur Xcrement]
Old 05-23-2016, 09:56 AM
  #283  
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Hi Guys, a quick update on this project. Yes it is still in the works. I completed the RK 049 fan and I get 3/4# thrust. From what I recall that is exactly what I got out of the .090 fan I built. Why am I not getting more thrust out of the .090 fan I built?
RP
Old 05-23-2016, 12:05 PM
  #284  
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Originally Posted by RickP View Post
Hi Guys, a quick update on this project. Yes it is still in the works. I completed the RK 049 fan and I get 3/4# thrust. From what I recall that is exactly what I got out of the .090 fan I built. Why am I not getting more thrust out of the .090 fan I built?
RP
.
You could try an oversized venturi and more nitro to see if that is holding the .09s RPM potential back.
Otherwise, it's the fan design that isn't taking advantage of the .09s higher torque. Higher torque must mean it can turn more blades, or more aggressive blades.
Old 05-26-2016, 09:45 AM
  #285  
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Combatpigg,
Well, I want to get good power out of the stock arrangement. If that doesn't work tweaking will only make minor improvements. I've tuned up the .090, ran it on the bench with a prop - I forget what prop but I think 17K was all I could get out of it. I have no way of measuring RPM in the fan. I need a contact tach for that and they are not available.
so I will run the RPK-702 next to the RK-049 and see if I can find more detailed info out. Just from looking at this thread I see I had 1# with the .090 and 3/4# with the 049. On top of that I never reported the overall weight. I know I'm really heavy. I am going to have the move the wing back and ditch the nose weight. That will help a ton. We will see.
Rick
Old 05-26-2016, 03:35 PM
  #286  
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Rick: I need a contact tach for that and they are not available.
In 1973 I bought a James G. Biddle mechanical tach for $131.04. I don't know if that company is still in business, but when I did an internet search, several used ones came up. Companies that were into manufacturing used them to measure many things including motor speed, and belt speed. It's possible you might find one in some company's tool crib that you could borrow. They do absorb a small amount of power. If we were closer, I'd loan you mine. Before optical tach's (with larger scales) I used my Biddle tach on all sizes of engines, but I don't think I ever tacked an .049.
Old 05-26-2016, 06:24 PM
  #287  
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Rick,
Per video the .09 was running at 16,795 rpm with slight fluctuations up to 16,876 rpm was running steady.
With that being said the weight of the rotor and spinner and shaft adapter kills the engine rpm to death..
Large center hub kills thrust. 7 blade meh a smaller hub and 4 blades would put out more static ounces
with a higher tail velocity. Less mass and drag more rpm. A cool looking rotor isn't going to make a hill
of beans if the thing can't perform. There are simplistic physical aspects that can't be fixed, the design
is flawed for a TD .09. Just the mass sticking way out past the prop hub kills rpm with no bearing support.
Great work on the over all project you deserve the pleasure of a good flying jet!

With that being said 40% nitro and a bored out venturi won't get the rpm's up high enough to have a screamer.
If you are hell bent to fly as is then at least that effort will get you another ounce or so of static thrust. Perhaps
you can source a turbo head adapter plug to squeeze out another 600 ish loaded rpm. 18.4k with all efforts.
In the air 22k if the DF Gods grace you.

Shorter spinner and some blade reworking could help to unleash some rpm.

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Old 05-27-2016, 10:48 AM
  #288  
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Pond in all my E ducted fans with telemetry or rpm on the speed controls the fans never unloaded and they all pulled the same amps on the ground as they did in flight. So based on that I don't think your fan will unload either.
Old 05-27-2016, 11:55 AM
  #289  
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Yes key word amps, inrunners and outrunners will produce more torque than an IC engine if
just matching HP. IC engines have a mechanical and induction change in the air.
If there is a state of extreme power to load ratio in conjunction to a reasonable length of ducting
you wont see any real changes.

Check out this, he has his mouse trap well set up less spinner
Calls it an .09 looks like a Norvel .074 best noted peak 19,763 rpm

https://www.youtube.com/watch?v=tnONVSSo-Jc
Typical example here:
Starts on the run out at 20kish rpm on take off
Loads on climb out then unloads to 24.3k at one point as an example.
IC is not windings and magnets rather a completely different aspect of power.

https://www.youtube.com/watch?v=SKSCsziaPZA

MAXEPF96F MAXX PRODUCTS HIMAX EPF96 Ducted Fan Unit

Good sample of how to grab more influx volume, blades get more bite
without the looses of a large dia. hub. min. weight and dia.
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Last edited by Pond Skipper; 05-27-2016 at 12:55 PM.

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