Mini F-16 vintage project consideration
#251
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RE: Mini F-16 vintage project consideration
ORIGINAL: combatpigg
Running the engine with backplate pressure will allow for aggressive launches and the most aggressive, consistant needle settings.
You need a fine thread needle for the best results though.
If a aftermarket fine thread needle isn't available, then a OS .10-.15 needle can be adapted...and it can be mounted basically anywhere on the plane you like since there is enough pressure to overcome the most convoluted plumbing jobs.
Running the engine with backplate pressure will allow for aggressive launches and the most aggressive, consistant needle settings.
You need a fine thread needle for the best results though.
If a aftermarket fine thread needle isn't available, then a OS .10-.15 needle can be adapted...and it can be mounted basically anywhere on the plane you like since there is enough pressure to overcome the most convoluted plumbing jobs.
http://www3.towerhobbies.com/cgi-bin...&I=LXCF85&P=OW
There is also one for the .15 CV-A I am not sure what the difference is but I can cut off the backplate and mount it remotely.
Two more questions. How do I blank off the NV at the Tee Dee? How would you suggest I plug the port at the nose?
Thanks!
RP
PS the .15CV-A is a RC buggy engine converted for aircraft use. It is a discontinued Ball Bearing engine. Any chance one NV is a finer pitch then the other?
#252
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RE: Mini F-16 vintage project consideration
Ooops..I forgot that OS changed to that style NVA. The old style NVA was all chromed steel and it threaded into the aluminum carb housing.
What you could do is buy a ASP .12 RC engine for $30 and borrow the NVA from that engine's carburetor. [the ASP.12 is a great little engine to own anyway..it is basically .10 size, twin ball bearing, ABC]
The NVA comes with a jamb nut, so it is very easy to adapt the NVA to a small home made bracket and mount it anywhere on the plane. A 3/32" thick scrap of nylon makes a durable bracket. The NVA uses a "clicker" piece to hold steady settings but the NVAs tend to leak under pressure. The fix is to set aside the clicker and go with a short hunk of fuel tubing pressed over the NVA.
Another avenue of approach is to use the old SuperTigre NVAs that had locking collets. They are still being sold IIRC by MECOA or even by Tower Hobbies if you ask them for special assistance.
To block off the stock TD NVA you need to cut the tip off the needle and screw it back in. push fuel tubing over the needle to keep it in place. Finding an old damaged needle to cannibalize might be a chore and it would be a shame to butcher a new one if they are scarce.
Last time I checked I have a small pile of stock TD .049 needles if one of those would work for you.
To plug the port at the nose...it's been so long since I had to do that [I did it to my first TD]...I'm not sure what I did .
To remove every trace of oil, place the part in a jar full of alcohol, screw on the lid and duct tape it to an orbital sander. Presto...HillBilly Sonic Cleaner. Denture cleaners work on the same principle. You could then try packing the orifice with JB Weld..but it's a PIA to wait several days for a full cure. RTV sealant might do the job better..? There still is a long wait for a full cure
What you could do is buy a ASP .12 RC engine for $30 and borrow the NVA from that engine's carburetor. [the ASP.12 is a great little engine to own anyway..it is basically .10 size, twin ball bearing, ABC]
The NVA comes with a jamb nut, so it is very easy to adapt the NVA to a small home made bracket and mount it anywhere on the plane. A 3/32" thick scrap of nylon makes a durable bracket. The NVA uses a "clicker" piece to hold steady settings but the NVAs tend to leak under pressure. The fix is to set aside the clicker and go with a short hunk of fuel tubing pressed over the NVA.
Another avenue of approach is to use the old SuperTigre NVAs that had locking collets. They are still being sold IIRC by MECOA or even by Tower Hobbies if you ask them for special assistance.
To block off the stock TD NVA you need to cut the tip off the needle and screw it back in. push fuel tubing over the needle to keep it in place. Finding an old damaged needle to cannibalize might be a chore and it would be a shame to butcher a new one if they are scarce.
Last time I checked I have a small pile of stock TD .049 needles if one of those would work for you.
To plug the port at the nose...it's been so long since I had to do that [I did it to my first TD]...I'm not sure what I did .
To remove every trace of oil, place the part in a jar full of alcohol, screw on the lid and duct tape it to an orbital sander. Presto...HillBilly Sonic Cleaner. Denture cleaners work on the same principle. You could then try packing the orifice with JB Weld..but it's a PIA to wait several days for a full cure. RTV sealant might do the job better..? There still is a long wait for a full cure
#257
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Hi Guys,
I'm sorry but I was in no rush to put this thing to the air. IMO it just wasn't ready. However, due to considerable pressure from my colleagues - I had to give it a shot and we gave it a test flight.
It shouldn't be a suprise to anyone here that there was not enough thrust to do anything meaningful. However, it did fly and I did make one pass around the field. After going downwind I just didn't have enough thrust to complete the upwind turn and it sunk into the weeds and a pile of wood chips.
There was no damage but the fan was still screaming when it settled down and I did ingest some wood chips. This did some damage to the inlet cone and eventually stalled the motor.
On the upside the fuel delivery system and engine ran perfectly. Rock solid and consistant untill the wood chip event. So the problem is not enough thrust. On my test bench I was getting 1/2 - 3/4 # if I recall correctly. I think even the RK-049 was rated at more than this. So probably my next steps will be to run and test the RK-049 I also built and see what kind of thrust I get with that. If it's more or on par with the .090 I built then I know I didn't get something quite right and maybe I can make some tweeks to that motor to increase thrust. I have a feeling that perhpas more efficient flow straighteners and perhaps a tighter blade tip to housing clearance might make the situation better. But for now I am pretty busy flying my IMAC sequences and I haven't had much time to fool with this.
FWIW, I compeated in the season finals at Black Dirt in Goshen NY and placed second in Sportsman. I am busy getting ready for next season. I think I am going make a pretty strong presance at those contests and see if I can place well overal in the North East region. Till then I will keep you updated if we make more progress on this thread.
A big thank you to you all for following and I'm sorry there is no video I can share at the moment....
RickP
I'm sorry but I was in no rush to put this thing to the air. IMO it just wasn't ready. However, due to considerable pressure from my colleagues - I had to give it a shot and we gave it a test flight.
It shouldn't be a suprise to anyone here that there was not enough thrust to do anything meaningful. However, it did fly and I did make one pass around the field. After going downwind I just didn't have enough thrust to complete the upwind turn and it sunk into the weeds and a pile of wood chips.
There was no damage but the fan was still screaming when it settled down and I did ingest some wood chips. This did some damage to the inlet cone and eventually stalled the motor.
On the upside the fuel delivery system and engine ran perfectly. Rock solid and consistant untill the wood chip event. So the problem is not enough thrust. On my test bench I was getting 1/2 - 3/4 # if I recall correctly. I think even the RK-049 was rated at more than this. So probably my next steps will be to run and test the RK-049 I also built and see what kind of thrust I get with that. If it's more or on par with the .090 I built then I know I didn't get something quite right and maybe I can make some tweeks to that motor to increase thrust. I have a feeling that perhpas more efficient flow straighteners and perhaps a tighter blade tip to housing clearance might make the situation better. But for now I am pretty busy flying my IMAC sequences and I haven't had much time to fool with this.
FWIW, I compeated in the season finals at Black Dirt in Goshen NY and placed second in Sportsman. I am busy getting ready for next season. I think I am going make a pretty strong presance at those contests and see if I can place well overal in the North East region. Till then I will keep you updated if we make more progress on this thread.
A big thank you to you all for following and I'm sorry there is no video I can share at the moment....
RickP
#259
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That's great that you got to see it fly Rick and you have a good feel for what it needs to be more air worthy.
I think campaigning a pattern plane would consume all your free time, so being able to tackle this project on the side says a lot about your love of the hobby.
I think campaigning a pattern plane would consume all your free time, so being able to tackle this project on the side says a lot about your love of the hobby.
#260
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That's great that you got to see it fly Rick and you have a good feel for what it needs to be more air worthy.
I think campaigning a pattern plane would consume all your free time, so being able to tackle this project on the side says a lot about your love of the hobby.
I think campaigning a pattern plane would consume all your free time, so being able to tackle this project on the side says a lot about your love of the hobby.
Thanks for the comments guys. It just goes to show it really doesn't matter what is on the other end of the transmitter - we are all addicted just the same LOL. please, don't call it pattern though LOL, IMAC is a different Genre and I don't want those guys to get the wrong idea ;-) We aren't done here - we will do some bench testing of the fans this fall and see what's what....
RP
#261
Well Hey, Thanks for the comments guys. It just goes to show it really doesn't matter what is on the other end of the transmitter - we are all addicted just the same LOL. please, don't call it pattern though LOL, IMAC is a different Genre and I don't want those guys to get the wrong idea ;-) We aren't done here - we will do some bench testing of the fans this fall and see what's what.... RP
Recently I peaked the curiosity of the MADS R/C Club members here in Clovis NM, when I showed up with an "ancient" 40" span Sureflite Cessna 180 foam job with a 1966 Enya .09-III TV and .09-.19 universal Tatone Peace Pipe muffler. The younger were unfamiliar with the engine, to which I explained. It hauled the plane through the sky really well. (Just a trifle bit nose heavy though, fairly fast and steep glide, will have to relocate servos surface mount to back and move receiver battery pack to balance. ) As an older baffle piston, it sips fuel from the 1 oz. tank and requires wider or larger props to keep in its lower RPM power range. I used an NOS TF 7x6 wood prop. Moves along like your plain bearing sport Schneurle .09's, .10's with 7x4 prop.
Looking forward to your tweaks to hone this F-16 further.
#262
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There was no damage but the fan was still screaming when it settled down
Last edited by subarubrat; 10-27-2013 at 10:19 PM.
#263
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Guys,
Thanks for the comments. I am sure this thing needs to loose weight. The big mistake I made with this is according to the plans the wing is too far forward and requires a TON of nose weight. I saw this as I was building but didn't do anything about it. I think if you look far enough back in this thread you will see the discussion.
My big dissappointment is with the amount of thrust my fan unit is making. According to the literature I am making less thrust with my Tee Dee .090 then the .049 fan makes. I have since built an actual RK-049. It's back on the bench, I have to break in the .049 and I want to take some thrust measurments first to see where I stand.
RP
Thanks for the comments. I am sure this thing needs to loose weight. The big mistake I made with this is according to the plans the wing is too far forward and requires a TON of nose weight. I saw this as I was building but didn't do anything about it. I think if you look far enough back in this thread you will see the discussion.
My big dissappointment is with the amount of thrust my fan unit is making. According to the literature I am making less thrust with my Tee Dee .090 then the .049 fan makes. I have since built an actual RK-049. It's back on the bench, I have to break in the .049 and I want to take some thrust measurments first to see where I stand.
RP
#265
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I built this same mini f-16 back int the early 80's but never got around to flying it.. But seeing that pic and plans really brought back some good memories..
#268
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We raced a 1/2A pylon class that anything could go as long as the wing was 200 sq. inch. Cox was the early engine as we moved to AME's, VA's and such. Many ran a bladder tank, especially Cox. Use of a Kraft needle valve was a must. We drilled out the venturi to the size in the Tee Dee .051 instruction sheet. They became another engine with a small prop. Seems they were a bit over 4 inches carved from a "black" 5x4 prop. Most often re pitched. We ran them about 22K and they seemed to out run their timing about 24K. Some other things I remember is that 1/4 inch latex put out about 6-8 psi. We ran 25% castor, high nitro and a touch of propylene oxide for our AME's and VA's. They turned up in the 30k range. In my opinion there is still much more power to be found. You need to get the load off the engine. WAG the .09 should be 20K+ to be happy. Surely there are some old 1/2A hot rodders out there??
Brooks
Brooks
#270
Just a side note and interesting, so the Tee Dee .09 put out about 177 Watts at about 18,500 RPM, or 0.24 HP. The Enya .09-III of about the same era put out 0.22 HP at about 12,500 RPM (0.16 for the TV throttled - RC version). Differences in philosophy. Then I gather the trick is to match the ducted fan impeller to the Tee Dee's torque curve.
I found this important, as with the Enya .09, it did not benefit running a 7x3 prop at higher RPM, but became a powerhouse when running a 7x6 prop loaded to its proper RPM.
With developments in the modern day electrics, I think a properly matched DF unit in this legacy nitro kit would be truly exhilarating to say nonetheless. It would break "traditional I'd like to see how they did it 30 years ago", but just to see one flying and performing as good as or even better than Bob Aberle hoped for would be tremendous.
I found this important, as with the Enya .09, it did not benefit running a 7x3 prop at higher RPM, but became a powerhouse when running a 7x6 prop loaded to its proper RPM.
With developments in the modern day electrics, I think a properly matched DF unit in this legacy nitro kit would be truly exhilarating to say nonetheless. It would break "traditional I'd like to see how they did it 30 years ago", but just to see one flying and performing as good as or even better than Bob Aberle hoped for would be tremendous.
Last edited by GallopingGhostler; 01-03-2014 at 02:38 PM.
#271
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I can't think of an application for a TD .09 that more badly needs every watt of available power.
Evidently the Enya was able to get a lot more charge into its cylinder than the TD, from your numbers we're talking almost 50% more torque at a bit over 2/3 the rpm.
Evidently the Enya was able to get a lot more charge into its cylinder than the TD, from your numbers we're talking almost 50% more torque at a bit over 2/3 the rpm.
#272
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Although the Enya's horsepower peaks out at about 18,000 RPM, its torque drops sharply off before there, torque being strongest in the mid range RPM's. Another engine article stated that there was no advantage to mounting props smaller than 7x4, as it was beyond the engine's power curve. Here, it mentioned the engine spun larger props with ease as large as 10x3.5.
The following is a statement from the article:
This unquestionably puts the 09-III in the top bracket of 09's so far as sheer power is concerned. So far as our personal experience goes, its peak power output is exceeded by only one other 09 (the Cox Tee-Dee 09) which, while developing a lower maximum torque than the Enya, peaks at higher rpm. Propped for speeds of up to 15,000 rpm, we know of no other motor of similar displacement that can beat the Enya 09-III.
#273
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I guess what I was trying to say in my previous post is….with the use of files, polish wheels and shims, I am sure you can make that .09 run just as we made the .049's run. Again calling all old school 1/2A race motor builders. I was just a pilot and did some of my engine work, my club mates were the engine guys. I know they are out there. I just sold my race motors, 4- AME, 2-George Aldrich VA's and 2 TD's, all .049. What little I have been around a Cox .09, they seem identical to the smaller .049's. Time them to turn up. They can scream! Someone said we were getting 300+watts from our AME and VA's. It took some one who knew how to do it. Most of them came from control line.
Brooks
Brooks
#275
I think there are a number of plain bearing sport engines that share similar high torque characteristics. The CL guys are using the K&B .20 Sportster, spins a 10x5 prop with ease.
Regarding RickP's lack of thrust, I think with a properly matched DF impeller it should perform more spiritedly than the .049 unit.
Regarding RickP's lack of thrust, I think with a properly matched DF impeller it should perform more spiritedly than the .049 unit.