P-38 Construction Project
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RE: P-38 Construction Project
Sorry I forgot to post the link
Here ya go
http://www.rcwarbirds.com/techniguespage.htm
Kram the Plated 38 has been working hard for us but has not been in the air yet, we have been using it to display our plating process but have plans to get her in the air before the end of this year. I have been working on a new project , its a Gamma that I have plated like the lightning. Heres the link to that.
http://www.rcuniverse.com/forum/m_25...mpage_4/tm.htm
Ron
Here ya go
http://www.rcwarbirds.com/techniguespage.htm
Kram the Plated 38 has been working hard for us but has not been in the air yet, we have been using it to display our plating process but have plans to get her in the air before the end of this year. I have been working on a new project , its a Gamma that I have plated like the lightning. Heres the link to that.
http://www.rcuniverse.com/forum/m_25...mpage_4/tm.htm
Ron
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RE: P-38 Construction Project
Finally got around to taking some new pictures.
The bird is getting close to done. I still have to work on a few more scale details including the cockpit.
Have to install the radio gear and get the flaps synchronized mechanically
The bird is getting close to done. I still have to work on a few more scale details including the cockpit.
Have to install the radio gear and get the flaps synchronized mechanically
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RE: P-38 Construction Project
dannost,
You asked about weight compairison vs. a royal 38. We have a royal P-38 which weighs about 14#, flying on a pair of OS.46s right now. Originally powered by fox .40s. It has fowler flaps as well and its really quite a joy to fly (if you put aside the worries of multi engine). The fowler flaps really help with the landings, much more than I'd ever imagined. We're going to take it out for a flight this week, if the weather holds. First time out for this year...
Good Luck with your's.
You asked about weight compairison vs. a royal 38. We have a royal P-38 which weighs about 14#, flying on a pair of OS.46s right now. Originally powered by fox .40s. It has fowler flaps as well and its really quite a joy to fly (if you put aside the worries of multi engine). The fowler flaps really help with the landings, much more than I'd ever imagined. We're going to take it out for a flight this week, if the weather holds. First time out for this year...
Good Luck with your's.
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RE: P-38 Construction Project
Thank you for the info. Mine feels like a brick, but the weight is about the same, so you have made me feel better.
How did you do the fowler flaps? Mine have a little play due to all the linkages. I'm thinking that with the air pushing only one way
on them there should be no worry of flutter, but I'm still a little concerned. How do yours feel?
How did you do the fowler flaps? Mine have a little play due to all the linkages. I'm thinking that with the air pushing only one way
on them there should be no worry of flutter, but I'm still a little concerned. How do yours feel?
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RE: P-38 Construction Project
Ours has very little play but it's no problem. We only deploy them on final. If I remember the video camera tomorrow, I'll show the flaps. One thing on ours, we get a major pitch up when the flaps are deployed.
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RE: P-38 Construction Project
Dannost
Are these KMP ARF Versions of P-38 shown in your pictures
Rgds
Phantom
Are these KMP ARF Versions of P-38 shown in your pictures
Rgds
Phantom
ORIGINAL: dannost
One more shot. Here it is with the prototype. The red one was modeled after "yippee", the 5000th
P38 built.
One more shot. Here it is with the prototype. The red one was modeled after "yippee", the 5000th
P38 built.
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RE: P-38 Construction Project
Dannost,
We got one flight on it this morning. There is some video, but it's not much... one aborted take off (nose wheel tucked under), one good take off, and most of one landing. Wish there were more. I checked the flaps on our 38 and we do have some play at the TE. about 1/16", maybe a bit more. However under (air) load they are all even. Hopefully you can see how well they let the plane land.
[link=http://jg14.com/video/P38_2005.wmv]Video Here[/link]
We got one flight on it this morning. There is some video, but it's not much... one aborted take off (nose wheel tucked under), one good take off, and most of one landing. Wish there were more. I checked the flaps on our 38 and we do have some play at the TE. about 1/16", maybe a bit more. However under (air) load they are all even. Hopefully you can see how well they let the plane land.
[link=http://jg14.com/video/P38_2005.wmv]Video Here[/link]
#34
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RE: P-38 Construction Project
Phantom,
Look through this post you will see that it is not an ARF. The booms, center wing and fuse are a one piece composite built by a friend that came with foam wing cores.
The rest is scratch built.
The size is almost the same as the Royal kit.
Look through this post you will see that it is not an ARF. The booms, center wing and fuse are a one piece composite built by a friend that came with foam wing cores.
The rest is scratch built.
The size is almost the same as the Royal kit.
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RE: P-38 Construction Project
Checkmate,
thanks for the video.
I'd still like to know how you did your fowlers? I got plans for some, but they were for a bigger bird and would not fit in the wing, so I had to change the servo setup.
thanks for the video.
I'd still like to know how you did your fowlers? I got plans for some, but they were for a bigger bird and would not fit in the wing, so I had to change the servo setup.
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RE: P-38 Construction Project
Dannost,
A couple of warnings... this plane is some 20+ years old, so we used "old technology" for the fowlers. It's a "design" that my father came up with on our first Royal P-38, which was close to 30 years ago. What we did was install three 90 degree bellcranks on each flap. One for each end of the flap (where you have the carbon tubes) and one in the middle of the flap which protrudes very slightly below the bottom of the wing at the TE (LE of the flap itself). We tied all the bellcranks together, and set the throws up so that the middle bellcrank didn't move quite as much as the outer two bellcranks (moved the connecting rod in one hole). So, the two outer bellcranks move slightly more than the middle bellcrank. Since that middle bellcrank attaches to the flap just below the wing surface, it acts to "pull" (or rotate) that part of the flap LE inward slightly.
I'm not sure if that explaination is clear enough... think of it this way... where you have a pushrod that pushes the flap back... we have two. One on each corner of the flap LE (and they slide in a track). Where you have one pushrod that acts to rotate the LE of the flap, we have one too (but it connects to a bellcrank, not a servo arm). Is that a better explaination?? I think this design causes a little binding through the middle of the motion, but it's not too bad. Where we get a little slop is just in the connection of the middle pushrod (it's hole has been enlarged over time). I could try to make a drawing, if it would help. It was a neat design 30 years ago (but heavy... we have a total of 14 bellcranks in the wing, including the ones for the ailerons). However, we drive all the flaps with one servo.
A couple of warnings... this plane is some 20+ years old, so we used "old technology" for the fowlers. It's a "design" that my father came up with on our first Royal P-38, which was close to 30 years ago. What we did was install three 90 degree bellcranks on each flap. One for each end of the flap (where you have the carbon tubes) and one in the middle of the flap which protrudes very slightly below the bottom of the wing at the TE (LE of the flap itself). We tied all the bellcranks together, and set the throws up so that the middle bellcrank didn't move quite as much as the outer two bellcranks (moved the connecting rod in one hole). So, the two outer bellcranks move slightly more than the middle bellcrank. Since that middle bellcrank attaches to the flap just below the wing surface, it acts to "pull" (or rotate) that part of the flap LE inward slightly.
I'm not sure if that explaination is clear enough... think of it this way... where you have a pushrod that pushes the flap back... we have two. One on each corner of the flap LE (and they slide in a track). Where you have one pushrod that acts to rotate the LE of the flap, we have one too (but it connects to a bellcrank, not a servo arm). Is that a better explaination?? I think this design causes a little binding through the middle of the motion, but it's not too bad. Where we get a little slop is just in the connection of the middle pushrod (it's hole has been enlarged over time). I could try to make a drawing, if it would help. It was a neat design 30 years ago (but heavy... we have a total of 14 bellcranks in the wing, including the ones for the ailerons). However, we drive all the flaps with one servo.
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RE: P-38 Construction Project
Dion,
This was intended to be a build thread, but there was not a lot of response and I got kind of lax with the pictures. There is a picture of
the superchargers unpainted in the beginning of the first page.
I'm still working on the cockpit. I will post some of those.
I had a lot of people asking how I made the superchargers, since they really add to the model.
This was intended to be a build thread, but there was not a lot of response and I got kind of lax with the pictures. There is a picture of
the superchargers unpainted in the beginning of the first page.
I'm still working on the cockpit. I will post some of those.
I had a lot of people asking how I made the superchargers, since they really add to the model.
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RE: P-38 Construction Project
Hey, i am currently building a royal p-38 kit and i was thinking about constructing some fowler flaps and was wondering if you could give me a bit more information on how to constuct them. Could you send me an e-mail at [email protected] , thank you for you time -Mark Thomas