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1/2A THRUST-O-METER

Old 02-27-2004, 09:44 AM
  #26  
Tim Wiltse-RCU
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Default RE: 1/2A THRUST-O-METER

Bruce,


Do you have more info on your power supply???


Thanks,
Tim
Old 02-27-2004, 01:23 PM
  #27  
combatpigg
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Default RE: 1/2A THRUST-O-METER

HI GANG! GUESS WHAT TIME IT IS?........ IT"S THRUST-O-METER TIME! Todays' competitor in the power lifting event is the NORVEL AME .061! This is the one that was in my 1/2A contest plane. I adjusted it for best compression with 30% fuel, ran it on bladder and here's what it did...

PROP RPM THRUST OZS

COX 5-3 21200 17.6

MAS 6-3 17900 20.0

MAS 5.5-4 22700 18.2

MAS 6-4 17600 19.2

ZINGALI 6-3 17900 14.8 OINK!

PUSHER 6-3 19600 reverse thrust

APC 5.7-3 21200 19.2

APC 5.5-2 24000 18.2

GRISH 5-3 24000 16.0

GRISH 5.5-4 17600 17.0

GRISH 4.5-4 21800 17.0

OPEN EXHAUST

MAS 6-3 18800 23.0

MAS 6-4 18500 22.4

APC 5.7-3 22600 22.4

APC 5.5-2 25600 22.2

GRISH 4.5-4 22500 17.6

I loaned my COX 6-4 out, that's why the results are missing, MAS 6-4 is a pretty close copy. The increase in power with open exhaust is relatively huge! A little bit of work to the stock muffler would pay dividends.
Old 02-27-2004, 02:02 PM
  #28  
MR Flyer57
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Default RE: 1/2A THRUST-O-METER

Great stuff CP!
This is the kind of data that makes sense to me!

MR Flyer57
Old 02-27-2004, 02:15 PM
  #29  
combatpigg
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Default RE: 1/2A THRUST-O-METER

That's right MARSHALL, what good are horse power figures? I can't exactly take an engine review with me down to the local drive-in on a SATURDAY night, and brag to the gear heads about my 1/4HP NORVEL! Now if I tell them about the 23 ozs of thrust, then they'll let me hang out with them![8D]!!
Old 02-27-2004, 02:45 PM
  #30  
MR Flyer57
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Default RE: 1/2A THRUST-O-METER

Seems to me there are a lot of ways to rate an engine, but what is important to me is speed and take off/ hover power.
Speed is something that can be played with forever, and is hard to measure. The power to stay in the air when you hand launch or want to hover seems to be the numbers that will do me the most good.
It will also help me make a decision on props. This stuff sure shows how just a few ounces of extra weight can crush your hovering dreams!
Seems a 23 oz plane is going to be a dog no mater what you do
Also thanks for including the rpms, I don't know if it matters, but I like to know.
Thanks again for all the readings,
MR Flyer57
Old 02-27-2004, 03:48 PM
  #31  
combatpigg
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Default RE: 1/2A THRUST-O-METER

HEY MARSHALL! Look at this one! This is the engine to send the kids to school with to fire up for SHOW and TELL. The FORA .049. It is a CYCLON clone, and was $20 cheaper. I haven't ever took reading off it till today, tuned it by ear, and lap times. The thrust is great, but you would need a real skinny fuselage to let the air from a 4" prop push against our atmosphere. I hated to run it with the 6" props, but it did the best pull with the 5.5-2. Here's the numbers....

PROP RPM THRUST OZS

COX 37/8"-3 34700 22.4 black rubber prop

COX 5-3 25200 23.0 I used to have a $20 TD that could do this

APC 41/8"- 2 36000 22.6 that's 600 revs per second

APC 5.5-2 26000 23.6 engine sounded happy

APC 5.7-3 21000 20.0 lugging, critical needle

MAS 6-3 15000 14.0 I apologized to the engine afterwards
Old 02-27-2004, 05:46 PM
  #32  
propjobbill
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Default RE: 1/2A THRUST-O-METER

Hi, Combat
I have a program that I downloaded for free from http://www.bmaps.net/ At the site click on goodies and there is a program there that will allow you to set rpm's type of prop and it tells you how mush your static thrust should be. I checked this against your results and they appear to be about the same as what this program shows.
The program is only 850K to down load. It also has a wing loading program built in Check it out. I think you will find the results interesting

http://www.bmaps.net/
Old 02-27-2004, 05:55 PM
  #33  
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Default RE: 1/2A THRUST-O-METER

ORIGINAL: MR Flyer57

Great stuff CP!
This is the kind of data that makes sense to me!

MR Flyer57

me too 57...

does this mean that it will fly a plane of that weight???

john
Old 02-27-2004, 06:10 PM
  #34  
combatpigg
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Default RE: 1/2A THRUST-O-METER

HI PROPJOB! WOW! Thanks for showing me that! I ran a sample problem of the 5.7-3 APC @21000 and the result was 1.4 lbs, which is exactly what I got. I've got it setup as a short cut on my computer now. What this program shows is a load figure that will tip off a pylon racer that he can get some free rpm, or a diesel freak who might accidently put on a prop that might snap the rod in half. I will be doing a diesel comparison when I get an APC 7-3 to work with. The range of props that make these diesel conversions work is limited. An MP JET 061 might be built heavy enough to tolerate a wider range of running conditions. I am going to predict that a dieselized BIG MIG 061 puts out more thrust than an AME on nitro, stay tuned! BTW this program shows that a 1-1 APC @ 100,000 rpm will take you up to 94.7 MPH, just in case there are any .010 enthusiasts looking in.
Old 02-27-2004, 08:45 PM
  #35  
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Default RE: 1/2A THRUST-O-METER

HI JBOY! If you have an engine mounted to a stick of wood, and the whole setup weighs a pound, the engine could put out 10 pounds of thrust and what would you have? If you put the same engine on a well designed plane that weighed 20 pounds, it could fly it, but the climb rate wouldn't be too hot. If you put the same engine on a plane that weighs 7 pounds, now you have a 3D plane that can hover, and explode out of a hover into a wild tumbling manuever. With 1/2A power, you can't afford to give any of it away, so it's good to know which prop works best for your application. It has become so easy to build a 240 sq. inch plane that is 4 channel, and weighs in the 12 to 16 oz range, that a reed 049 with 9ozs of thrust could fly it pretty well, and an 061 with 20 ozs of thrust could hover it.
Old 02-28-2004, 02:34 AM
  #36  
Remby
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Default RE: 1/2A THRUST-O-METER

Very Cool! Are you going to run tests for Cox engines? A TD .049, lets see what it can do. Sure would give the flyers just what they need to know as far as engines, props, etc.
A great addition to engine info! thanks!
Remby
Old 02-28-2004, 02:41 AM
  #37  
combatpigg
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Default RE: 1/2A THRUST-O-METER

HI REMBY! I did a TD on page one of this post. A COX BABY BEE was done in a recent[but seperate] post about reed engine rpm.
Old 02-28-2004, 02:47 AM
  #38  
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Default RE: 1/2A THRUST-O-METER

Yes, saw that. I ment to ask about a Medallion , not the TD. My Goof. Would be nice to know the diference to a newer medallion with the duel fuel ports. Let us know!
Remby
Old 02-28-2004, 03:56 AM
  #39  
combatpigg
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Default RE: 1/2A THRUST-O-METER

HI REMBY, I don't have access to a MEDALLION, but you could tach yours, then plug those #s into the thrust calc program and come out very close, plus you get to know how fast it will go.
Old 02-29-2004, 10:55 AM
  #40  
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Default RE: 1/2A THRUST-O-METER

ORIGINAL: combatpigg

HI JBOY! If you have an engine mounted to a stick of wood, and the whole setup weighs a pound, the engine could put out 10 pounds of thrust and what would you have? If you put the same engine on a well designed plane that weighed 20 pounds, it could fly it, but the climb rate wouldn't be too hot. If you put the same engine on a plane that weighs 7 pounds, now you have a 3D plane that can hover, and explode out of a hover into a wild tumbling manuever. With 1/2A power, you can't afford to give any of it away, so it's good to know which prop works best for your application. It has become so easy to build a 240 sq. inch plane that is 4 channel, and weighs in the 12 to 16 oz range, that a reed 049 with 9ozs of thrust could fly it pretty well, and an 061 with 20 ozs of thrust could hover it.


combat,
what your saying is,you want a plane that weighs less than the amount of thurst an engine can produce...is that right???

i really like the way your meter works out to be very accurate...have you check any of the norvels yet...i'm wanting to see the difference between the TD.049 and the norvel.049...is the norvel really stronger than the TD???

john
Old 02-29-2004, 01:13 PM
  #41  
Remby
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Default RE: 1/2A THRUST-O-METER

6-3 MAS 16300 16.8 mistaken for COX in previous tests

6-4 COX 16500 16.2 outdone by MASTER AIRSCREW

5.7-3 19200 16.8 hard to beat

5.5-2 22500 16.8 better for 3D, and throttle response

The above info may show somthing about RPM range. A engine runs at a certain RPM within a "power band", where the engine's thrust is produced at max power. The tests copyed above shows the 6-6 Master Airscrew to get this at a much lower RPM than the 5-7, or 5-2 pitch props. To my knoledge, this saves fuel, & the lower RPM produces less heat along with less wear of the engine. So, it looks like the ideal choice for sport flying. If this is wrong, please let me know .
Remby
Old 02-29-2004, 02:54 PM
  #42  
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Default RE: 1/2A THRUST-O-METER

HI REMBY! Yep, you are on the right track. But there are no blanket statements that can be made that are true for everything. The lower rpm setups will give you better mileage, I think that statement holds true, as long as the prop is a good design for that rpm, and the plane it is bolted to can fly well slowly. The ZINGALI 6-3 that I tested is a narrow blade, hard plastic, looks beautiful, and it gave good rpm on a 061, but the thrust numbers were pathetic, the only way this prop would work would be to spin it faster than any of the engines that have been tested could do. The chart you have there has numbers that don't make sense unless you consider the different brands of props have their own personalities. The 5.5-2 APC spins faster than the 6-3 COX and has the same thrust. In real life, the 6-3 will make the engine run hotter, and make the ideal needle setting more critical, and have worse throttle response than the 5.5-2. At 22000 rpm the 5.5-2 can create a fist full of it's own drawbacks, vibration, noise, lack of speed, etc. The prop load is a factor of pitch and diameter, and that is what determines the strain on the parts and it has an effect on heat. HI JBOY! Yep, a good sport flyer that has more thrust than what it weighs will give you more ways to explore what that plane can do.
Old 03-01-2004, 12:44 PM
  #43  
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Default RE: 1/2A THRUST-O-METER

Should would like to see apc make a 6.5x2 prop for the .061s. Would be great for producing thrust.
Old 03-01-2004, 03:11 PM
  #44  
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Default RE: 1/2A THRUST-O-METER

HI MYWAY! Yes, that sounds good, they should make a 7-2 also for 3D flight. I wonder how much trouble it is for them to introduce a new size? They created the 6-2 and 5.5-2 as an answer to the Free Flight guys needs, I believe. The 1/2A business is pretty hot right now, and the range of prop choices will improve. Right now if I want a 4-4 prop I have to clip the ends off of a MAS 6-4, and I'll bet APC could make a better 4-4 than I can with my side cutters![:'(]
Old 03-03-2004, 12:11 AM
  #45  
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Default RE: 1/2A THRUST-O-METER

combatpigg

Thanks for the info, I will use this to find a good overall flying prop for my setups. Considering what you said, should give me a bit to do before I zero in based on the data you gave. I found the Master Airscrew to be pretty good, and have wrecked a model because of a lower thrust prop, so I tent to use what I found works from trial & error.. Soper forum here!


Remby
Old 03-03-2004, 01:45 AM
  #46  
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Default RE: 1/2A THRUST-O-METER

HI REMBY! Have you tried that THRUST HP program yet? The link was given a few replies ago. Once you download it, it will become a permanent and very useful tool in your "programs" section of the computer.
Old 09-10-2009, 05:14 AM
  #47  
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Default RE: 1/2A THRUST-O-METER

combatpigg, what Norvel 061 was in your tests, AME or BigMig?
Did you test Norvel 074?

Thanks,
Kostya
Old 09-10-2009, 06:53 AM
  #48  
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Default RE: 1/2A THRUST-O-METER

Salat, Thanks for bringing this post back up!

CP in your tests it looks like for "our" kind of planes the overall winner would be MAS 5.5x4 Good thrust and pitch speed !
Mr Cox mentioned this prop in Salat's cox prop thread - I've had a few of these but never gotten around to mounting one up.

PROP RPM THRUST OZS

COX 5-3 21200 17.6

MAS 6-3 17900 20.0

MAS 5.5-4 22700 18.2

MAS 6-4 17600 19.2
Old 09-10-2009, 07:40 AM
  #49  
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Default RE: 1/2A THRUST-O-METER

Salat, it looks like I just tested the AME. Never did test the .074. The only prop that makes sense to run with the .074 is the 7x3, so testing different props on an engine with a single mission didn't make sense to me. I've goofed around with different props on the .074 but then you are converting this magnificent engine into a role that a hot .049-.061 can do just as well if not better.
The Thrust HP calculator says that a 7x3 prop at 17,000 rpm puts out 2 pounds of thrust, almost a kilogram. They say the engine is developing .25 HP to do so, which sounds possible.

Rob, the 5.5x4 is a prop I never use full length on .049-.061s. These work real well on 120-150 square inch racers when cut down to4.5- 4.2". The MAS 6x4 is what I start out with and just snip the tips off. I think they pull some of the racers better than the 4.2x4 APC.
Old 09-10-2009, 09:15 PM
  #50  
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Default RE: 1/2A THRUST-O-METER

CP, is there a Master Airscrew prop that works on the Norvel .074? I know the APC 7x3 seems perfect, but I want something a bit more durable.

One of these days I will build something, put this engine in it, and bring it over to your side of the Sound for show and tell!

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