Balsa USA 1/4 Sopwith Pup build
#226
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RE: Balsa USA 1/4 Sopwith Pup build
#227
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RE: Balsa USA 1/4 Sopwith Pup build
I found a decent pilot http://www.jimreeves.plus.com/ Scroll down to "McCudden"
Here is the pic of him
Regards Mark
Here is the pic of him
Regards Mark
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RE: Balsa USA 1/4 Sopwith Pup build
ORIGINAL: 5blue
Anyone have photos of pull pull elevator configuration for there Pup - really don;t want to use a push rod - for the elevators and would like to have individual elevator halfs - just for fun along with pull pull for rudder
Anyone have photos of pull pull elevator configuration for there Pup - really don;t want to use a push rod - for the elevators and would like to have individual elevator halfs - just for fun along with pull pull for rudder
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RE: Balsa USA 1/4 Sopwith Pup build
Hey Guys,
I also decided to go with the DLE 30, and it's length presents a problem with keeping the front end looking scale. Moving the mounting surface farther back, puting the carb inside the fuse, all that requires mods that are just to much, and a pain in the backside.
I made an extension to the fuselage that gives me the extra length in front of the firewall so I can mount the cowl far enough forward. I used the stock engine mounts which puts the engine where the CG is looking like it may be right on.
See the pictures.
I also decided to go with the DLE 30, and it's length presents a problem with keeping the front end looking scale. Moving the mounting surface farther back, puting the carb inside the fuse, all that requires mods that are just to much, and a pain in the backside.
I made an extension to the fuselage that gives me the extra length in front of the firewall so I can mount the cowl far enough forward. I used the stock engine mounts which puts the engine where the CG is looking like it may be right on.
See the pictures.
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RE: Balsa USA 1/4 Sopwith Pup build
Thanks senrak. Another good idea to consider. If you get a chance, post a picture with the cowl installed. Would love to see what it looks like. I like your choke setup.
Kevin
Kevin
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RE: Balsa USA 1/4 Sopwith Pup build
My Pup is nearing completion. I need to install rudder/elevater pushrods, radio, paint wheels, etc.
Complete enough for some pictures though.
Kevin,
I don't know. Doesn't seem too long in front here. Maybe if you put next to a truely scale Pup the differences would show. All that doesn't matter much to me. I just want my planes to be fun, and not be a hassle at the field.
Complete enough for some pictures though.
Kevin,
I don't know. Doesn't seem too long in front here. Maybe if you put next to a truely scale Pup the differences would show. All that doesn't matter much to me. I just want my planes to be fun, and not be a hassle at the field.
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RE: Balsa USA 1/4 Sopwith Pup build
If you would have went with a G-26 it would have fit about perfect and had plenty of power. I only had to use very little to bring it out to meet the cowling. I know the DLE30 is a REALLY nice motor but it is going to be WAY more than you need for that plane.
#235
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RE: Balsa USA 1/4 Sopwith Pup build
ORIGINAL: senrak
My Pup is nearing completion. I need to install rudder/elevater pushrods, radio, paint wheels, etc.
Complete enough for some pictures though.
Kevin,
I don't know. Doesn't seem too long in front here. Maybe if you put next to a truely scale Pup the differences would show. All that doesn't matter much to me. I just want my planes to be fun, and not be a hassle at the field.
My Pup is nearing completion. I need to install rudder/elevater pushrods, radio, paint wheels, etc.
Complete enough for some pictures though.
Kevin,
I don't know. Doesn't seem too long in front here. Maybe if you put next to a truely scale Pup the differences would show. All that doesn't matter much to me. I just want my planes to be fun, and not be a hassle at the field.
Your plane looks so beautiful that you have no reason whatsoever to have any complain.
If you have some then you have to complain to the builder. It will lead you nowhere because the builder has refined his building abilities to the utmost level of perfection.
CONGRATULATIONS on a super looking model and I say that in absolute sincerity.
Zor
#237
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RE: Balsa USA 1/4 Sopwith Pup build
Great work senrak, I had a similar idea myself, looking at your pics has made up my mind.
My Mustang has a dle 30, I'm going to put a pte36 in her so the dle30 will have a new home now
I was leaning that way anyway as the engine further forward means less, or perhaps no weight in the nose.
I like the idea of a more powerful engine so you can use less rpm (ie noise) and swing a bigger prop, I'm still considering the 36 for it as it has the same stand off length and the same weight.
Is that the metal cowl or the plastic one? I ended up getting the metal one, just can't bring myself to paint it, but that red looks striking, should be easy to pick up in the sky.
Make sure you post a video of the maiden, looks great!
Regards Mark
My Mustang has a dle 30, I'm going to put a pte36 in her so the dle30 will have a new home now
I was leaning that way anyway as the engine further forward means less, or perhaps no weight in the nose.
I like the idea of a more powerful engine so you can use less rpm (ie noise) and swing a bigger prop, I'm still considering the 36 for it as it has the same stand off length and the same weight.
Is that the metal cowl or the plastic one? I ended up getting the metal one, just can't bring myself to paint it, but that red looks striking, should be easy to pick up in the sky.
Make sure you post a video of the maiden, looks great!
Regards Mark
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RE: Balsa USA 1/4 Sopwith Pup build
HEY SENRAK EWAN HERE
WHAT DID YOU USE FOR COVERING? IT LOOKS TRANSPERANT ON THE FUSE. IAM COVERING THE WINGS RIGHT NOW WITH
21ST CENTURY FABRIC, THE FLAT AREAS LOOK GREAT AND THE BOTTOM WING TIPS. BUT IT DOESNT WANT TO STREACH AROUND
THE TOP SIDE FOR SOME REASON. NOT TO MENTION WHEN I STARTED A NEW ROLE, IT WAS A DIFFERANT SHADE. ATLEAST IAM
GOING TO PAINT THE TOP OF THE WINGS.
ALSO I I HOPE YOU ARE GOING TO ADD A SPREADER BAR ON YOUR LANDING GEAR, THEY WONT LAST LONG LIKE THAT.
MY SEA5 THAT I BOUGHT AT A SWAP MEET DIDNT HAVE ONE, ONLY LASTED ONE LANDING AND IT IS ALOT SMALLER.
ANYWAY YOUR PLANE LOOKS GREAT. AT THIS RATE IT WILL BE JUNE FOR OUR MAIDENS, WITH ALL THE SNOW NOW. [:'(]
LATER EWAN
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RE: Balsa USA 1/4 Sopwith Pup build
Wow Guys. Thanks for the nice comments. I spend a lot of time building and trying to do the best I can with what I have. It is good to know that people appreciate this stuff.
I'm using Solertex from BUSA. It is expensive, but is easily the best covering I have ever used. It's color is a part of the fabric, not a part of the glue. It's seems to have more glue than other covering I have used. That seems to make a big difference in how it adheres to the structure. It holds on like grim death. It also shrinks and stretches better then most I have tried. The fabric itself is about as strong as Sig's Koverall, and if you have ever used that you know how tough it is. Some of the colors are translucent, and others are solid. The rolls I bought were long enough so there were no different shades.
I know what you mean about a spreader bar. One hard landing will put the wheels right into the bottom of the wing. I'll come up with something, I just haven't worked it out. I would like it to be flexible and shock absorbing.
I hoping to be able to run this engine at low speeds. The sound of a screming two stoke in this airplane just isn't appropriate, but I couldn't afford the engine I really wanted to put in it.
Regards, Dale
I'm using Solertex from BUSA. It is expensive, but is easily the best covering I have ever used. It's color is a part of the fabric, not a part of the glue. It's seems to have more glue than other covering I have used. That seems to make a big difference in how it adheres to the structure. It holds on like grim death. It also shrinks and stretches better then most I have tried. The fabric itself is about as strong as Sig's Koverall, and if you have ever used that you know how tough it is. Some of the colors are translucent, and others are solid. The rolls I bought were long enough so there were no different shades.
I know what you mean about a spreader bar. One hard landing will put the wheels right into the bottom of the wing. I'll come up with something, I just haven't worked it out. I would like it to be flexible and shock absorbing.
I hoping to be able to run this engine at low speeds. The sound of a screming two stoke in this airplane just isn't appropriate, but I couldn't afford the engine I really wanted to put in it.
Regards, Dale
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RE: Balsa USA 1/4 Sopwith Pup build
here's a good example of a easy spreader bar with rubber bands (not mine but one I photographed) from a good friends (cliffs ) puppy
#242
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RE: Balsa USA 1/4 Sopwith Pup build
ORIGINAL: ALO 111
Some pics of the pull-pull as promised .
Also finished rib stitching and roundels. I like the weathered oily look .
Some pics of the pull-pull as promised .
Also finished rib stitching and roundels. I like the weathered oily look .
The pictures are showing a very nice workmanship.
I am just curious ___you do not seem to have used the Ackerman principle in your pull-pull installation.
Zor
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RE: Balsa USA 1/4 Sopwith Pup build
Zor,
You have made me curious.
How do you apply the ackerman principal to a pull-pull system on single surface like a rudder or elevater?
Please explain.
You have made me curious.
How do you apply the ackerman principal to a pull-pull system on single surface like a rudder or elevater?
Please explain.
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RE: Balsa USA 1/4 Sopwith Pup build
5blue,
How is the spreader bar on your example held to the landing gear strut? It appears to be only by the rubber band. Is that the case?
DW
How is the spreader bar on your example held to the landing gear strut? It appears to be only by the rubber band. Is that the case?
DW
#245
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RE: Balsa USA 1/4 Sopwith Pup build
ORIGINAL: senrak
Zor,
You have made me curious.
How do you apply the ackerman principal to a pull-pull system on single surface like a rudder or elevater?
Please explain.
Zor,
You have made me curious.
How do you apply the ackerman principal to a pull-pull system on single surface like a rudder or elevater?
Please explain.
First an explanation about my comment.
Looking at your first pic on the left, you have an arm on the servo on which the lines to the feather is on a straight line (apparently) with the axis of the servo rotation. That measns that the pulling line and the give line travel the same linear length.
Again, I often post "how I do certain things" and it does not mean that I am ordering people around. Anyone can do what they like. So here is how I install a pull-pull system.
I want the lines such that they do not put lots of tension on the bearings of the servo output shaft.
I do not want any slop and I use some flexible stainless steel lines about .020" dia. Something rated at 20 lbs or more on tension. I instatl some guides and frictionless supports pretty well at all fuselage formers and route for a traight line all the way.
Servos with ball bearing on the output shafts can stand more tension than those with bushings. (wear factors).
I use threaded clevis to adjust the slight tension in the servo neutral (centered) position.
When the servo rotates I want the give line to travel just a tiny bit more than the pull line without becoming loose. .
Thus the analogy to the Ackerman principle in which the inner front wheel of a turning vehicle follows a smaller circle than the outer wheel. The inner wheel turns more degrees than the outer wheel.
To achieve this the lines to the featherare installed on the servo arm a bit more forward thanthe servo rotation axis. Typically about 5 degrees so the front angle is 170 degrees and the rear angle is 190 degrees.
It is easily done using a circle piece (ususally supplied with a purchased servo) and drilling the two tiny holes.
This geometry makes that the giving line passes the 90 degree point going backward and has a bit more motion than the pulling line according to the sine of the rotation angles.
Some guys may disagree but it will not bother me.
Cheers,
Zor
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RE: Balsa USA 1/4 Sopwith Pup build
Hey Zor,
Okay, I see what you're getting at. But what advantage would there be to a setup like that?
The only possible advantage I can to see is maybe less pressure on the shaft bearing, and then only at certain times.
DW
Okay, I see what you're getting at. But what advantage would there be to a setup like that?
The only possible advantage I can to see is maybe less pressure on the shaft bearing, and then only at certain times.
DW
#247
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RE: Balsa USA 1/4 Sopwith Pup build
ORIGINAL: senrak
Hey Zor,
Okay, I see what you're getting at. But what advantage would there be to a setup like that?
The only possible advantage I can to see is maybe less pressure on the shaft bearing, and then only at certain times.
DW
Hey Zor,
Okay, I see what you're getting at. But what advantage would there be to a setup like that?
The only possible advantage I can to see is maybe less pressure on the shaft bearing, and then only at certain times.
DW
I posted how I do it.
You do it the way you feel like doing it. ( This line is just repeating myself ).
I did not claim any advantage.
My apologies for asking if you had considered it.
My intention was not to criticize what you had already done.
All I did is respond to your question how do I apply the principle.
Sorry for my big mouth. I would have considered it impolite to not bother replying to your question.
Zor
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RE: Balsa USA 1/4 Sopwith Pup build
ORIGINAL: Zor
Why repeat myself ?
I posted how I do it.
You do it the way you feel like doing it. ( This line is just repeating myself ).
I did not claim any advantage.
My apologies for asking if you had considered it.
My intention was not to criticize what you had already done.
All I did is respond to your question how do I apply the principle.
Sorry for my big mouth. I would have considered it impolite to not bother replying to your question.
Zor
ORIGINAL: senrak
Hey Zor,
Okay, I see what you're getting at. But what advantage would there be to a setup like that?
The only possible advantage I can to see is maybe less pressure on the shaft bearing, and then only at certain times.
DW
Hey Zor,
Okay, I see what you're getting at. But what advantage would there be to a setup like that?
The only possible advantage I can to see is maybe less pressure on the shaft bearing, and then only at certain times.
DW
I posted how I do it.
You do it the way you feel like doing it. ( This line is just repeating myself ).
I did not claim any advantage.
My apologies for asking if you had considered it.
My intention was not to criticize what you had already done.
All I did is respond to your question how do I apply the principle.
Sorry for my big mouth. I would have considered it impolite to not bother replying to your question.
Zor
Wow. Easy. I wasn't criticizing anyone and I didn't think you were either. The example you are looking at wasn't even my post. They belong to ALO 111. I have never used a pull-pull, and was only trying to learn.
Sorry, I didn't mean to piss you off.
DW
#249
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RE: Balsa USA 1/4 Sopwith Pup build
ORIGINAL: Zor
Why repeat myself ?
I posted how I do it.
You do it the way you feel like doing it. ( This line is just repeating myself ).
I did not claim any advantage.
My apologies for asking if you had considered it.
My intention was not to criticize what you had already done.
All I did is respond to your question how do I apply the principle.
Sorry for my big mouth. I would have considered it impolite to not bother replying to your question.
Zor
ORIGINAL: senrak
Hey Zor,
Okay, I see what you're getting at. But what advantage would there be to a setup like that?
The only possible advantage I can to see is maybe less pressure on the shaft bearing, and then only at certain times.
DW
Hey Zor,
Okay, I see what you're getting at. But what advantage would there be to a setup like that?
The only possible advantage I can to see is maybe less pressure on the shaft bearing, and then only at certain times.
DW
I posted how I do it.
You do it the way you feel like doing it. ( This line is just repeating myself ).
I did not claim any advantage.
My apologies for asking if you had considered it.
My intention was not to criticize what you had already done.
All I did is respond to your question how do I apply the principle.
Sorry for my big mouth. I would have considered it impolite to not bother replying to your question.
Zor
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RE: Balsa USA 1/4 Sopwith Pup build
ORIGINAL: 5blue
here's a good example of a easy spreader bar with rubber bands (not mine but one I photographed) from a good friends (cliffs ) puppy
here's a good example of a easy spreader bar with rubber bands (not mine but one I photographed) from a good friends (cliffs ) puppy
Doug