E Flite AT-6 Texan Convert to GLOW!
#101
RE: E Flite AT-6 Texan Convert to GLOW!
> Victory! (well, kinda'...)
Iwas finally able to get the Harvard into the sky for a one flight maiden and it flew wonderful after I was able to get all things trimmed out. 3/4 throttle and it cruises nicely and banks like a dream (of course, props to the pilot .. yeah, I'm pumping my own ego here... haha!).The only snafu is my engine lost power unexpectedly and I had to land "off field" in the high grasses / shrubs since it happened during a lower fly by. One gear slightly bent, wing ding, and some paint chips but, all is good. As long as I can get the engine issue solved, I'm a very happy camper.
E-flite T-6 Texan Conversion to Glow = LIKE!
Iwas finally able to get the Harvard into the sky for a one flight maiden and it flew wonderful after I was able to get all things trimmed out. 3/4 throttle and it cruises nicely and banks like a dream (of course, props to the pilot .. yeah, I'm pumping my own ego here... haha!).The only snafu is my engine lost power unexpectedly and I had to land "off field" in the high grasses / shrubs since it happened during a lower fly by. One gear slightly bent, wing ding, and some paint chips but, all is good. As long as I can get the engine issue solved, I'm a very happy camper.
E-flite T-6 Texan Conversion to Glow = LIKE!
#103
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RE: E Flite AT-6 Texan Convert to GLOW!
I am glad it flew good. C.G. good? You will have to show us some video!
I am still sanding the glass job. I'll be on that for a while. The trailing edges warped a little above the flaps on mine. Maybe I can straighten them with a heat gun. Still trying to figure what to do with the cockpit.
I am still sanding the glass job. I'll be on that for a while. The trailing edges warped a little above the flaps on mine. Maybe I can straighten them with a heat gun. Still trying to figure what to do with the cockpit.
#104
RE: E Flite AT-6 Texan Convert to GLOW!
> Truly Baffling
I've been able to narrow down my engine issues to overheating. While I do have a completely open cowl, the out-flow of air is weak due to too small of an exit region at the bottom of the cowl used for the muffler. Additionally, I need to build some engine baffling to help redirect the airflow out as it's getting trapped inside.
So my engines still tuned great and purr's at 2600RPM on the low end and 12,100RPM on the high end (running rich). I just need to make one more modification and we're flying again. I'll be certain to post pics and maybe a video if I can get one recorded sooner then later.
@scale dail
What's wrong with your cockpit? Or are you thinking of building it out?
@scale dail
What's wrong with your cockpit? Or are you thinking of building it out?
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RE: E Flite AT-6 Texan Convert to GLOW!
No cheesy ARF plastic cockpit for me! I'll make my own. But I need to decide how deep to go with it. Yes our oil burners do need some air flow. Mine will need the same mods.
Still sanding resin!
Still sanding resin!
#106
RE: E Flite AT-6 Texan Convert to GLOW!
> The "real" Maiden
Unfortunately I do not have any in-flight video or images of the North American during my flights today so the attached image will have to serve as proof. I ventured out in the 100+ degree weather on a mission, whilst my wife (the photographer) decided it was best to save her sanity and stay cool. Of course, afterward, I realized she was the smart one.
Regardless, I got in a solid 12+ minutes of flight time today. One flight with gear down and the other flight gear up. The baffling worked great and after landing the engine temp was good; even on a scorching hot day. On final approach of flight 2 a strong cross wind knocked me about causing a prop strike but no other damage. As for flight characteristics; with an O.S. .25 you'll get a more scale-like take off since it needs more time to get up its airspeed. You won't be able to do huge loops, sustained inverted flight, or other more extreme maneuvers but, that's not what I wanted anyway.
I'll be sure to get some in-flight pix and video when my wife has the opportunity to get out with me. Till then, I'll say it again… This project was a great one.
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RE: E Flite AT-6 Texan Convert to GLOW!
Congrats! Glad the cooling issue is better.
Looking forward to video. I know it is very hard to get video. I just bought a still camera that does video. But, who is going to run it???
I have my wing glassed and sanded. My fuse is all glassed and I have just started sanding. It is starting to pick up weight now.
Looking forward to video. I know it is very hard to get video. I just bought a still camera that does video. But, who is going to run it???
I have my wing glassed and sanded. My fuse is all glassed and I have just started sanding. It is starting to pick up weight now.
#108
RE: E Flite AT-6 Texan Convert to GLOW!
> Baffling? I don't see no stinkin' baffling
For anyone who's curious or wondering, here are a few pictures of the engine "baffling" that I installed into my E-flite Texan. I quote "baffling" because by definition what I did was more along the lines of velocity cooling. Either way, I stopped all the air from flowing out the back of the cowl (by original design) and forced it around the engine, down around the muffler, and out the bottom. And after two solid flights if found this solution worked really well.
For anyone who's curious or wondering, here are a few pictures of the engine "baffling" that I installed into my E-flite Texan. I quote "baffling" because by definition what I did was more along the lines of velocity cooling. Either way, I stopped all the air from flowing out the back of the cowl (by original design) and forced it around the engine, down around the muffler, and out the bottom. And after two solid flights if found this solution worked really well.
#109
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RE: E Flite AT-6 Texan Convert to GLOW!
Very nice baffle. I will use the dummy engine to restrict intake air. I like the baffle idea. I'll probably make a simpler set up inside mine. My engines always run a little hot.
#110
RE: E Flite AT-6 Texan Convert to GLOW!
I think your engine is starving for cooling airflow at flying speeds. I have always followed the "one-third-rule" and never had cooling problems. You need to have more exit-airflow than enter-airflow. If you wish to keep your baffle then either add dummy engine cylinders or a simple lite-ply ( painted black ) front "cover" just on the inside of the cowl opening with a "slice" removed to only alow air to get to the carb and pass around the cylinder. That "slice" should be approx. one-third the size of your exit area.
If your engine stays cool with your setup.....then please forget the above recommendation
....however, if your engine starts to show visable signs of running too lean ( tarnish forming on the cylinder ) then try something different.
Nice work on the "bashing"/ modifications of this model. Looks great.
Good luck.
Ken.
If your engine stays cool with your setup.....then please forget the above recommendation
....however, if your engine starts to show visable signs of running too lean ( tarnish forming on the cylinder ) then try something different.
Nice work on the "bashing"/ modifications of this model. Looks great.
Good luck.
Ken.
#111
RE: E Flite AT-6 Texan Convert to GLOW!
@Ken
I'm not too familiar with the 1/3 rule. At first I was contemplating building out what you mentioned above (as I have a faux engine cover) but, I was worried such a small opening wouldn't give me the air flow I needed.Does the 1/3 rule create more of a venturi effect? How does it increased the airflow through the space? It seems odd that smaller is better but, I'm never set in my ways and always looking to learn more.
_andrew
_andrew
#112
RE: E Flite AT-6 Texan Convert to GLOW!
Andrew,
Yes a "venturi effect" does occure and will aide in "sucking" the air through and out. If the intake air-volume is more than the outflow volume then the air can't escape fast enough to provide cooling of the fins on the engine's head. The air swirls and loitters and heats up because it simply has nowhere to go.
As far as the ratio : one-third is just a starting point to get you off the ground safely and you can then expierment with the size of exit area according to how your engine is running at all power applications. The ratio can be and probably will be changed a bit to optimize cooling. Obviously during extreme cold weather flying you may need to close off some exit area in order to keep the engine running smoothly but I've never had to face that situation here in Southern California.
Take a look at Sean Tucker's red ( highly modified ) Pitts Challenger's intake volume. There are only very tiny narrow slots in the front and the cowl is a "pressurized" type.
If you can see the trailing edge of the exit hole at the bottom of the cowl, you'll see a small "lip" that creates a void or vacumm around the openning. This little "lip" sticks out into the airstream like cowl flaps on a radial engine and provides a kind of suction or draft that helps pull the hot air out of the cowl. Look at the WWII trainer, the Fairchild PT-19 and you'll see a simular feature on the bottom of the rear edge of the cowl. It's "old-school" technology but very effective.
Just remember you want more exit area than intake area. The faster the plane flys...the closer the ratio can be. Conversely, the slower planes need more exit volume.
You also have the gap between the trailing edge of the cowl and the fuselage / firewall as exit area to include in your computation. If you add a dummy engine and remove one dummy cylinder from the front of the carburator and cooling fins, that should provide plenty of cooling unless you are using a high performance race engine and not alowing the plane to fly fast enough for proper airflow.
I hope this helps you get going in the right direction.
Ken.
Yes a "venturi effect" does occure and will aide in "sucking" the air through and out. If the intake air-volume is more than the outflow volume then the air can't escape fast enough to provide cooling of the fins on the engine's head. The air swirls and loitters and heats up because it simply has nowhere to go.
As far as the ratio : one-third is just a starting point to get you off the ground safely and you can then expierment with the size of exit area according to how your engine is running at all power applications. The ratio can be and probably will be changed a bit to optimize cooling. Obviously during extreme cold weather flying you may need to close off some exit area in order to keep the engine running smoothly but I've never had to face that situation here in Southern California.
Take a look at Sean Tucker's red ( highly modified ) Pitts Challenger's intake volume. There are only very tiny narrow slots in the front and the cowl is a "pressurized" type.
If you can see the trailing edge of the exit hole at the bottom of the cowl, you'll see a small "lip" that creates a void or vacumm around the openning. This little "lip" sticks out into the airstream like cowl flaps on a radial engine and provides a kind of suction or draft that helps pull the hot air out of the cowl. Look at the WWII trainer, the Fairchild PT-19 and you'll see a simular feature on the bottom of the rear edge of the cowl. It's "old-school" technology but very effective.
Just remember you want more exit area than intake area. The faster the plane flys...the closer the ratio can be. Conversely, the slower planes need more exit volume.
You also have the gap between the trailing edge of the cowl and the fuselage / firewall as exit area to include in your computation. If you add a dummy engine and remove one dummy cylinder from the front of the carburator and cooling fins, that should provide plenty of cooling unless you are using a high performance race engine and not alowing the plane to fly fast enough for proper airflow.
I hope this helps you get going in the right direction.
Ken.
#113
RE: E Flite AT-6 Texan Convert to GLOW!
> Proofs In The Pix
Since we can't seem to post more then one pic per thread in the elect-2-glow converstion thread, here's a few pictures of the Texan on a fly-by. The weather was perfect for flying but, not so much for pictures since we had low, very dark clouds rolling through. Either way, one more in the next thread of a landing.
_andrew
Since we can't seem to post more then one pic per thread in the elect-2-glow converstion thread, here's a few pictures of the Texan on a fly-by. The weather was perfect for flying but, not so much for pictures since we had low, very dark clouds rolling through. Either way, one more in the next thread of a landing.
_andrew
#115
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RE: E Flite AT-6 Texan Convert to GLOW!
Nice! Looking good!
It is hot in the shop these days! Progress is slow on mine. I am dying to post a pic, but all I have is this one again. Someday I'll have mine done...
It is hot in the shop these days! Progress is slow on mine. I am dying to post a pic, but all I have is this one again. Someday I'll have mine done...
#116
RE: E Flite AT-6 Texan Convert to GLOW!
@Scale Dail
No worries here. Take your time… I'm just excited to show off the aircraft now that I've gotten the jitters out having not flow in over a year and being uber protective of a more personal build (vs. an ARF 8 hour assemble).Additionally, I have a SBD-3 Dauntless Guillows kit that's been 1/3 complete for over a year, still sitting in the box. I'm converting to electric with working retracts, etc. Think this build, only smaller! I even had a thread at one time:
Take ur time Scale. Isn't that what this is all about? Cheers!
No worries here. Take your time… I'm just excited to show off the aircraft now that I've gotten the jitters out having not flow in over a year and being uber protective of a more personal build (vs. an ARF 8 hour assemble).Additionally, I have a SBD-3 Dauntless Guillows kit that's been 1/3 complete for over a year, still sitting in the box. I'm converting to electric with working retracts, etc. Think this build, only smaller! I even had a thread at one time:
#117
RE: E Flite AT-6 Texan Convert to GLOW!
@Ken
Thanks for the heads up on the cowling / cooling. I know I've run into issues like that in the past and I think the longer in the tooth I get in this hobby the more and more I realize what I don't know.After a solid 3 runs this weekend the engine was performing quite well but, I think it might be a bit hotter then it should. Which begs the question of what is a "red line" temperature for running glow engines? Does a temp range even exist?
I've been contemplating a temp gun for a while but, I'm the kind of person that loves to mess around with my engines (take them apart, inspect them, rebuild them, etc.) and loves to keep them in optimal condition. Plus, having it to experiment with baffling / running temps would help since "to the touch" measuring is completely inaccurate (and painful).
_andrew
Thanks for the heads up on the cowling / cooling. I know I've run into issues like that in the past and I think the longer in the tooth I get in this hobby the more and more I realize what I don't know.After a solid 3 runs this weekend the engine was performing quite well but, I think it might be a bit hotter then it should. Which begs the question of what is a "red line" temperature for running glow engines? Does a temp range even exist?
I've been contemplating a temp gun for a while but, I'm the kind of person that loves to mess around with my engines (take them apart, inspect them, rebuild them, etc.) and loves to keep them in optimal condition. Plus, having it to experiment with baffling / running temps would help since "to the touch" measuring is completely inaccurate (and painful).
_andrew
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RE: E Flite AT-6 Texan Convert to GLOW!
Now that the weather has cooled off I am back to it. I have my whole airframe primed and sanded ready for surface detail. Working on the cockpit. I am using my own stuff to build that. Glow power. I will not discuss anything else! Pictures soon.
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RE: E Flite AT-6 Texan Convert to GLOW!
What fun is a post, without a picture. I do not believe this ARF is available from Horizon anymore, so maybe I'll just show what I am doing to inspire others to bash their ARF's a little more.
I am making my own cockpit out of materials from around my shop. Here is the panel. 1/16th ply. The holes are being driled out with a tulip shaped dremel tool. I have a set of J Tec instruments that will go in. I am copying a pic in the Squadron AT-6 in action book of an AT-6C front panel.
I am making my own cockpit out of materials from around my shop. Here is the panel. 1/16th ply. The holes are being driled out with a tulip shaped dremel tool. I have a set of J Tec instruments that will go in. I am copying a pic in the Squadron AT-6 in action book of an AT-6C front panel.
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RE: E Flite AT-6 Texan Convert to GLOW!
Yes, two in fact. I bought a Century jet 1/7th Military pilot for it, but it is too big. I have experimented on it by cutting it up to make it a little smaller. That will be the front pilot. I have an old vacu formed pilot for the back. I'll have to do a little work on that one too.
Why do all this work to an ARF when it's just going to crash anyway? That's not how I think.
Why do all this work to an ARF when it's just going to crash anyway? That's not how I think.