1/5 scale Bell P-39 Aircobra...
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RE: 1/5 scale Bell P-39 Aircobra...
Al,
As for the dual servos on the elevator, I, unfortunately, experienced the failure of a solo elevator servo on a final approach. Let's just say it wasn't pretty. Dual servos here would be a real plus.
Sorry to hear about that. I have also experienced this loss when I was younger and had to rebuild my Skylark on it's maiden flight due to a servo failure. It was a brand new servo too!!
Welding rod would certainly be strong enough but would'n't that be rather heavy?
I would just be using them for the small torque rods in the Hstab/elevator assembly. I will be using carbon fiber pushrods for the run to the servos.
But for most of us, this would be an exercise in frustration when all we really want is a knockout plane to fly on the weekends.
Ditto, This isn't going to be a show plane or a hanger queen. I like to fly all of my airplanes, and they all are workhorses.
Best Regards to all,
Darrell
As for the dual servos on the elevator, I, unfortunately, experienced the failure of a solo elevator servo on a final approach. Let's just say it wasn't pretty. Dual servos here would be a real plus.
Sorry to hear about that. I have also experienced this loss when I was younger and had to rebuild my Skylark on it's maiden flight due to a servo failure. It was a brand new servo too!!
Welding rod would certainly be strong enough but would'n't that be rather heavy?
I would just be using them for the small torque rods in the Hstab/elevator assembly. I will be using carbon fiber pushrods for the run to the servos.
But for most of us, this would be an exercise in frustration when all we really want is a knockout plane to fly on the weekends.
Ditto, This isn't going to be a show plane or a hanger queen. I like to fly all of my airplanes, and they all are workhorses.
Best Regards to all,
Darrell
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RE: 1/5 scale Bell P-39 Aircobra...
The main problem with the "drive shaft" idea is that the drive shaft of that length will not stand the "impulses" from a single cylinder engine. Or so I have read, I am not an engineer.
#28
RE: 1/5 scale Bell P-39 Aircobra...
Why not just put the reduction unit near the engine? That way the long shaft for the prop does not spin at high RPM, and should be easier to make. If it only spins at 3-4000rpm I guess the vibrations would be way less.
Take a look at Mick Reeves reduction unit for the G-62. That may give you some ideas.
Take a look at Mick Reeves reduction unit for the G-62. That may give you some ideas.
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RE: 1/5 scale Bell P-39 Aircobra...
Well the weekened is over and I had a few minutes to work on my P-39. I was able to figure out that I'm going with the torque rod and will order the DuBro parts that I need to accomplish this. That is OK, I can still build up the bottom of the stab and sheet it. Then on to the V stab.
I'm sorry if this is taking forever, I'm also trying to deal with taking care of my mom, who had a fall before Christmas, and is now in a nursing home. With any luck, I can talk her Doctor into letting her move in with my family, and I won't have to drive on Saturdays to go check on her. That should give me a little more building time.
Anyway, here are a couple of more pics of the H stab. The ruller is an 18"s for refference.
Good Luck to all,
Darrell
I'm sorry if this is taking forever, I'm also trying to deal with taking care of my mom, who had a fall before Christmas, and is now in a nursing home. With any luck, I can talk her Doctor into letting her move in with my family, and I won't have to drive on Saturdays to go check on her. That should give me a little more building time.
Anyway, here are a couple of more pics of the H stab. The ruller is an 18"s for refference.
Good Luck to all,
Darrell
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RE: 1/5 scale Bell P-39 Aircobra...
Darrel,
I too have put some thought into building a P-39 and placing the engine in the scale location. As far as cooling goes, Vaily Aviation makes a scale cooling fan for their Focke Wulf 190 that could be used on your shaft inside your fuse to constantly circulate air past your engine cylinder. I think you can rout enough fresh air in using the top mounted scale scoop and the wing leading edge air inlets. Air can be routed out using the scale wing air outlet ducts in the trailing edge area of the wing center section. Don't be afraid to rig up a small fan like the ones that cool computer drives. You will likely have plenty of room in that fuse to get creative and they don't weigh much. It would just take another battery pack. The fan does not have to move at full speed as long as it pushes air past the engine. Great thread. Scale model building is a problem solving event from start to finish....that is what makes it fun. razorback11
I too have put some thought into building a P-39 and placing the engine in the scale location. As far as cooling goes, Vaily Aviation makes a scale cooling fan for their Focke Wulf 190 that could be used on your shaft inside your fuse to constantly circulate air past your engine cylinder. I think you can rout enough fresh air in using the top mounted scale scoop and the wing leading edge air inlets. Air can be routed out using the scale wing air outlet ducts in the trailing edge area of the wing center section. Don't be afraid to rig up a small fan like the ones that cool computer drives. You will likely have plenty of room in that fuse to get creative and they don't weigh much. It would just take another battery pack. The fan does not have to move at full speed as long as it pushes air past the engine. Great thread. Scale model building is a problem solving event from start to finish....that is what makes it fun. razorback11
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RE: 1/5 scale Bell P-39 Aircobra...
Thought that I would give an update on the P-39. I finished framing the horizontal stab, and it is ready for the bottom sheeting. I think I remembered everything, but if you think you see something I missed, please chime in.
Thanks,
Darrell
Thanks,
Darrell
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RE: 1/5 scale Bell P-39 Aircobra...
Are the Consolidated plans still available? I wouldn't mind a 100'ish wingspan model.
I found the Palmer plans site but am a little confused. They only recommend a .91 two-stroke. What's up with that????
Thanks,
Mike
I found the Palmer plans site but am a little confused. They only recommend a .91 two-stroke. What's up with that????
Thanks,
Mike
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RE: 1/5 scale Bell P-39 Aircobra...
Mike,
I know that Palmer is very overly optemistic about his final weights on all of his planes, especially these. He also tends to underpower them. That said, it is supposed to be a fair set of plans, some issues with parts not fitting. There is a guy on the ScaleRCBuilder sight that is building one.
I don't know about the consolidated plans. I thought that they were a kit, or composit that was for sale?
Sorry I don't know more,
Darrell
I know that Palmer is very overly optemistic about his final weights on all of his planes, especially these. He also tends to underpower them. That said, it is supposed to be a fair set of plans, some issues with parts not fitting. There is a guy on the ScaleRCBuilder sight that is building one.
I don't know about the consolidated plans. I thought that they were a kit, or composit that was for sale?
Sorry I don't know more,
Darrell
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RE: 1/5 scale Bell P-39 Aircobra...
The Consolodated plans do not have enough info to scartch build, as the it was a glass & foam kit. There is a large kit available from American Eagle that is almost a copy of the Consolodated model.
http://www.flyrcmodels.com/
http://www.flyrcmodels.com/
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RE: 1/5 scale Bell P-39 Aircobra...
New update for all of you balsa dust sniffers!
I have the first half of the elevators built, as well as the H stab compleated except for final sanding to shape. The elevators need to be turned over and the bottoms built, as well as hinge pockets drilled, and final shaping on them as well. Next I'll start on the rudder and V stab. I also need to make copies of the wing ribs so that I can start cutting them out.
I have the first half of the elevators built, as well as the H stab compleated except for final sanding to shape. The elevators need to be turned over and the bottoms built, as well as hinge pockets drilled, and final shaping on them as well. Next I'll start on the rudder and V stab. I also need to make copies of the wing ribs so that I can start cutting them out.
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RE: 1/5 scale Bell P-39 Aircobra...
I thought that I would post a few updated pictures. These are of the elevator counter balances. On the plans he says to use soft blocks for the counter balances. I chose to loose a little weight, and used some 3/32 balsa formers, and 1/16 sheeting to build them up. The results are very nice, and light.
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RE: 1/5 scale Bell P-39 Aircobra...
Hello everyone,
I'm sorry for the slow progress with this build. I hope that you aren't getting board of waiting. Family has been sick. Mom has been in hospital with pneumonia. I have been trying to figure out some of the things that Pepino wants off of the plans. You know, the usual shoping list of reasong why we procrastinate on something....
I'll try to get some new pictures up in the next day or so. I have made some progress on the H-stab, and elevators, V-stab, rudder, and center section of the wing.
I'm also trying to decide, since Pepino didn't design any building tabs into the wing ribs, how that I'm going to build a straight wing?
Best Regards,
Darrell
I'm sorry for the slow progress with this build. I hope that you aren't getting board of waiting. Family has been sick. Mom has been in hospital with pneumonia. I have been trying to figure out some of the things that Pepino wants off of the plans. You know, the usual shoping list of reasong why we procrastinate on something....
I'll try to get some new pictures up in the next day or so. I have made some progress on the H-stab, and elevators, V-stab, rudder, and center section of the wing.
I'm also trying to decide, since Pepino didn't design any building tabs into the wing ribs, how that I'm going to build a straight wing?
Best Regards,
Darrell
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RE: 1/5 scale Bell P-39 Aircobra...
To build a straight wing or one with washout you can use a piece of wood and angle it from root to tip not parrallel of the spar. Ziroli does this. You will have to figure out the angle though. Platt uses a tapered piece of wood also not quite parrallel to the spar but having washout. If you know the center line of the root and tip then you can measure from that.
Carl
Carl
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RE: 1/5 scale Bell P-39 Aircobra...
Darrell,
I'm glad to see that your project is still active. You're making good progress and things are really looking sharp. The planking will add "flesh" to the fuselage and really get you motivated!
How did things work out with the retracts? The pictured nose gear looks great. How do the mains look to you?
Did you get the plug for the nose to Fiberglass Specialties?
Keep those pictures coming, Darrell. You're doing a fine job!
Al
I'm glad to see that your project is still active. You're making good progress and things are really looking sharp. The planking will add "flesh" to the fuselage and really get you motivated!
How did things work out with the retracts? The pictured nose gear looks great. How do the mains look to you?
Did you get the plug for the nose to Fiberglass Specialties?
Keep those pictures coming, Darrell. You're doing a fine job!
Al
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RE: 1/5 scale Bell P-39 Aircobra...
Al,
The retracts are very nice and I think that the rear swept struts on the mains will really add to the realism of the plane when it is standing on the ground. The nose gear is fantastic and works great.
I e-mailed back and forth with Craig, and he wanted me to wait until after he got back from Toledo next week, so I'm still waiting.
Yes I'm really looking forward to putting some meat on this birds bones, and will start this afternoon. The wind is blowing like crazy, and I can't get out and fly today.
Carl,
I was just thinking that. I don't think that I will put any washout into the wing. It looks like Pepino has used a thicker airfoil toward the tip, than the root, which will cause the tips to stall after the wing root. I like the idea of using little 1/16 balsa pieces cut to the same length as the centerline at the main spar and tack glueing them to the back of the ribs to hold the thrust line straight. Then just building everything flat and straight.
Good luck to all,
Darrell B.
The retracts are very nice and I think that the rear swept struts on the mains will really add to the realism of the plane when it is standing on the ground. The nose gear is fantastic and works great.
I e-mailed back and forth with Craig, and he wanted me to wait until after he got back from Toledo next week, so I'm still waiting.
Yes I'm really looking forward to putting some meat on this birds bones, and will start this afternoon. The wind is blowing like crazy, and I can't get out and fly today.
Carl,
I was just thinking that. I don't think that I will put any washout into the wing. It looks like Pepino has used a thicker airfoil toward the tip, than the root, which will cause the tips to stall after the wing root. I like the idea of using little 1/16 balsa pieces cut to the same length as the centerline at the main spar and tack glueing them to the back of the ribs to hold the thrust line straight. Then just building everything flat and straight.
Good luck to all,
Darrell B.
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RE: 1/5 scale Bell P-39 Aircobra...
Darrell,
What I would do in this case, is put and accurate centerline on each rib, front to back. Then use an angle finder, incidence meter, etc, to set each center line at the same angle to building board, using the small supports on the ribs.
This may be exactly what you were describing in your previous post. If so ignore this.
What I would do in this case, is put and accurate centerline on each rib, front to back. Then use an angle finder, incidence meter, etc, to set each center line at the same angle to building board, using the small supports on the ribs.
This may be exactly what you were describing in your previous post. If so ignore this.
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RE: 1/5 scale Bell P-39 Aircobra...
Well, here are a few pictures of the sheeting as it looks at this point. I have mounted my first attempt at a foam plug for the cowl, and my spinner to get a better idea of the final length, and shape. My foam plug for Craig at fiberglass specialties is safely waiting for his return from Toledo. I don't like the shape of the spinner that I have, but I can't afford the True Turn P-38 or P-40 spinners. They want $175 each plus the adapters. Ouch!
Good Luck to all.
Darrell
Good Luck to all.
Darrell
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RE: 1/5 scale Bell P-39 Aircobra...
Darrell,
In two of your pictures you have a canopy placed atop the fuselage. Did you make this yourself or was it purchased? Another question goes back to the retracts: will robart make the gear they made for you available to others? Your project really has my interest piqued!
Al
In two of your pictures you have a canopy placed atop the fuselage. Did you make this yourself or was it purchased? Another question goes back to the retracts: will robart make the gear they made for you available to others? Your project really has my interest piqued!
Al
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RE: 1/5 scale Bell P-39 Aircobra...
Al,
The canopy is the Sig large WW 2. According to the plans, you use the top middle section of this, along with some flat plastic sheeting, and a 1/32 plywood frame, to make the actual canopy that will go on the airplane.
I assume that Robart would be glad to make another set of the retracts that I ordered. If they don't have them, I can give you the specs that they built them by.
thanks for your interest in my project.
Darrell
The canopy is the Sig large WW 2. According to the plans, you use the top middle section of this, along with some flat plastic sheeting, and a 1/32 plywood frame, to make the actual canopy that will go on the airplane.
I assume that Robart would be glad to make another set of the retracts that I ordered. If they don't have them, I can give you the specs that they built them by.
thanks for your interest in my project.
Darrell