CY/ET Yak 3U/Yak 11 96"
06-21-2016, 04:16 AM
#76
Thread Starter
Have not taken any more pictures than the ones earlier in this thread :-)
No nast things from this plane unless you make it tail heavy....just like all other planes :-)
I have removed some lead in the nose because it felt like was nose heavy.
Will see tomorrow.
No nast things from this plane unless you make it tail heavy....just like all other planes :-)
I have removed some lead in the nose because it felt like was nose heavy.
Will see tomorrow.
06-21-2016, 08:24 PM
#78
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HI Guys,
It has been a while since I last posted on this thread. I apologize for not providing those gear block measurements. I must have had a mental blank and missed that post completely.
My Yak 3U build is progressing well I have installed and hooked up all the servos but the rudder/pull-pull and tailwheel. Only Items remaining are final fitting of retracts and covers into wings and mounting the engine, though I will need to modify and shorten the engine box. The plywood is quite thin also so I may just beef this up.
I have noticed there were a number of dry joints between the fiberglass walls and the plywood formers and cross plates intersections. So I have used Hysol to go over this completely as I do not want any issues downtrack or during the models lifespan.
I am looking forward to completing this project as it has been on the to do list for quite some time as I have been distracted with other projects.
I will be using JR 28X transmitter with JR DMSS 11ch powersafe receiver along with RPM and Temperature telemetry sensors.
The servos I have used are Power HD 1218TH 6V, 0.18sec/60deg, 18kg or 7V, 0.16sec/60deg, 21kg. I have run some tests on these on the servo tester and they appear to work well.
I was going to install a lado retractable tailwheel but I may just stick with the stock fixed tailwheel at least for now. I can always later add the lado retract tailwheel.
I will post some photos of my build soon.
It has been a while since I last posted on this thread. I apologize for not providing those gear block measurements. I must have had a mental blank and missed that post completely.
My Yak 3U build is progressing well I have installed and hooked up all the servos but the rudder/pull-pull and tailwheel. Only Items remaining are final fitting of retracts and covers into wings and mounting the engine, though I will need to modify and shorten the engine box. The plywood is quite thin also so I may just beef this up.
I have noticed there were a number of dry joints between the fiberglass walls and the plywood formers and cross plates intersections. So I have used Hysol to go over this completely as I do not want any issues downtrack or during the models lifespan.
I am looking forward to completing this project as it has been on the to do list for quite some time as I have been distracted with other projects.
I will be using JR 28X transmitter with JR DMSS 11ch powersafe receiver along with RPM and Temperature telemetry sensors.
The servos I have used are Power HD 1218TH 6V, 0.18sec/60deg, 18kg or 7V, 0.16sec/60deg, 21kg. I have run some tests on these on the servo tester and they appear to work well.
I was going to install a lado retractable tailwheel but I may just stick with the stock fixed tailwheel at least for now. I can always later add the lado retract tailwheel.
I will post some photos of my build soon.
06-22-2016, 12:47 AM
#79
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Be very careful with those Power HD servos, I had them in a P-51 as flap servo's and they got so hot the plastic case was melting. I heard from other modellers that they had the same experience.
I only buy Hitec 645MG servos for my warbirds and these are very rubust and reliable.
I only buy Hitec 645MG servos for my warbirds and these are very rubust and reliable.
06-22-2016, 09:07 AM
#80
Thread Starter
Great day out today, and it still is awesome in the air.
Will have to build a cockpit for it soon, and install the gear doors on the landing gear
https://www.youtube.com/watch?v=IiOr-k5tRic&feature=youtu.be
Will have to build a cockpit for it soon, and install the gear doors on the landing gear
https://www.youtube.com/watch?v=IiOr-k5tRic&feature=youtu.be
06-22-2016, 02:26 PM
#82
Thread Starter
Yea, realy happy with it. Its still breaking in, and feels better after each flight. I can begin to lean it a bit soon. The guys realy like the sound of it, and new poeple allways come over to see what it is :-)
And it realy sips fuel...... Runs for ever on a tank
And it realy sips fuel...... Runs for ever on a tank
06-22-2016, 09:29 PM
#84
Join Date: Jun 2008
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Hi Guys,
Thanks for the heads up with the HD Servos. I will do some more testing. I have experienced an issue once before which was quality control. I have inspected a few of the servos I have installed into the Yak and they appeared fine. I will keep a close eye on these ie: rx voltage telemetry for any issues.
I did a bit more work on my Yak last night and completed the rudder pull pull hookup. Yes the overspray as you can see in the photo is disappointing and I may even repaint the areas of concern or bite the bullet and redo entire plane. That said I will complete the model and fly as is for now.
The tail wheel install needs to be completed but I had a problem with the plastic arm brass collet thread stripping. So I have decided I will make a metal horn and solder it on
I have also noticed I have an earlier version kit with the alloy style control horns. I had to do a bit of additional work to get the flaps to seat with the inside skin of the wing as otherwise the bolt heads and washers would have prevented the flaps from retracting fully. I simply countersunk the screws into the flap hard wood. There appeared to be plenty of wood for the bolts to cradle.
I also opted to rotate the retract legs so the trailing links face forward just like the prototype aircraft. In doing so I have boxed up the channels to tidy this up and just need prime and paint white to match the underside.
I will have another look over the Evolution 160 radial as I want to get this running on the bench properly. Previous attempts the motor only ran for short time before quitting.
Thanks for the heads up with the HD Servos. I will do some more testing. I have experienced an issue once before which was quality control. I have inspected a few of the servos I have installed into the Yak and they appeared fine. I will keep a close eye on these ie: rx voltage telemetry for any issues.
I did a bit more work on my Yak last night and completed the rudder pull pull hookup. Yes the overspray as you can see in the photo is disappointing and I may even repaint the areas of concern or bite the bullet and redo entire plane. That said I will complete the model and fly as is for now.
The tail wheel install needs to be completed but I had a problem with the plastic arm brass collet thread stripping. So I have decided I will make a metal horn and solder it on
I have also noticed I have an earlier version kit with the alloy style control horns. I had to do a bit of additional work to get the flaps to seat with the inside skin of the wing as otherwise the bolt heads and washers would have prevented the flaps from retracting fully. I simply countersunk the screws into the flap hard wood. There appeared to be plenty of wood for the bolts to cradle.
I also opted to rotate the retract legs so the trailing links face forward just like the prototype aircraft. In doing so I have boxed up the channels to tidy this up and just need prime and paint white to match the underside.
I will have another look over the Evolution 160 radial as I want to get this running on the bench properly. Previous attempts the motor only ran for short time before quitting.
Last edited by Ozflyboi; 06-22-2016 at 09:33 PM.
06-23-2016, 12:36 AM
#85
Thread Starter
Looks good.
I could not install the wheel well linings because of the angle of the wheels are when they are retracted. Try install the strut and wheel, and align the wheel so it tracks streight, and yoy will see that when retracted, the leading edge of the wheel is much deeper in the wheel well than the aft portion of the wheel. I even raised the retracts by shimming them, and had to dremel a bit of the rib on the top surface of the skin to fit the big tire. Buying slimmer Dubro wheels would help here
I could not install the wheel well linings because of the angle of the wheels are when they are retracted. Try install the strut and wheel, and align the wheel so it tracks streight, and yoy will see that when retracted, the leading edge of the wheel is much deeper in the wheel well than the aft portion of the wheel. I even raised the retracts by shimming them, and had to dremel a bit of the rib on the top surface of the skin to fit the big tire. Buying slimmer Dubro wheels would help here
06-24-2016, 01:26 PM
#88
My Feedback: (8)
Looks good.
I could not install the wheel well linings because of the angle of the wheels are when they are retracted. Try install the strut and wheel, and align the wheel so it tracks streight, and yoy will see that when retracted, the leading edge of the wheel is much deeper in the wheel well than the aft portion of the wheel. I even raised the retracts by shimming them, and had to dremel a bit of the rib on the top surface of the skin to fit the big tire. Buying slimmer Dubro wheels would help here
I could not install the wheel well linings because of the angle of the wheels are when they are retracted. Try install the strut and wheel, and align the wheel so it tracks streight, and yoy will see that when retracted, the leading edge of the wheel is much deeper in the wheel well than the aft portion of the wheel. I even raised the retracts by shimming them, and had to dremel a bit of the rib on the top surface of the skin to fit the big tire. Buying slimmer Dubro wheels would help here
06-30-2016, 12:59 AM
#90
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Sonnich,
Does the plane have any tendency to nose over during landing? Do you advice to add some wood on the backward gear trail IOT bring the wheels more forward?
Nice work on those gear doors!
Does the plane have any tendency to nose over during landing? Do you advice to add some wood on the backward gear trail IOT bring the wheels more forward?
Nice work on those gear doors!
Last edited by patrick verlinden; 06-30-2016 at 01:01 AM.
06-30-2016, 01:11 AM
#91
Thread Starter
Hi Patrick.
It depends on where your CG is :-)
When I first flew it, I thought the elevator was very sensitive, and assumed it was tail heavy, so I added weight in the nose......lots.....
It did make it fly more stable
But that caused the plane to be very light on the tail wheel, and I was concerned that it would nose over....I would not dare taxi it back after landing because it was so close to nosing over.
So I shimmed the landing gear slightly on the rear mouns to get them forward. And that solved the problem.
But after flying the plane alot more, I have removed alot of the nose weight again, and reduced elevator throw, and put some expo on it too.
The plane now flys more neutral. But I do have some down elevator for level flying.
Going to do some more dive test with the motor at idle to see if I need more down thrust on my engine, as I feel the CG is realy good now.
But now, when flying level, and I chop the throttle, the plane does not seem to change attitude....
So it is up to where you have the CG.
But I would say it is fine as it is. you can always change it later on.
It depends on where your CG is :-)
When I first flew it, I thought the elevator was very sensitive, and assumed it was tail heavy, so I added weight in the nose......lots.....
It did make it fly more stable
But that caused the plane to be very light on the tail wheel, and I was concerned that it would nose over....I would not dare taxi it back after landing because it was so close to nosing over.
So I shimmed the landing gear slightly on the rear mouns to get them forward. And that solved the problem.
But after flying the plane alot more, I have removed alot of the nose weight again, and reduced elevator throw, and put some expo on it too.
The plane now flys more neutral. But I do have some down elevator for level flying.
Going to do some more dive test with the motor at idle to see if I need more down thrust on my engine, as I feel the CG is realy good now.
But now, when flying level, and I chop the throttle, the plane does not seem to change attitude....
So it is up to where you have the CG.
But I would say it is fine as it is. you can always change it later on.
06-30-2016, 10:22 AM
#92
My Feedback: (8)
Hi Patrick.
It depends on where your CG is :-)
When I first flew it, I thought the elevator was very sensitive, and assumed it was tail heavy, so I added weight in the nose......lots.....
It did make it fly more stable
But that caused the plane to be very light on the tail wheel, and I was concerned that it would nose over....I would not dare taxi it back after landing because it was so close to nosing over.
So I shimmed the landing gear slightly on the rear mouns to get them forward. And that solved the problem.
But after flying the plane alot more, I have removed alot of the nose weight again, and reduced elevator throw, and put some expo on it too.
The plane now flys more neutral. But I do have some down elevator for level flying.
Going to do some more dive test with the motor at idle to see if I need more down thrust on my engine, as I feel the CG is realy good now.
But now, when flying level, and I chop the throttle, the plane does not seem to change attitude....
So it is up to where you have the CG.
But I would say it is fine as it is. you can always change it later on.
It depends on where your CG is :-)
When I first flew it, I thought the elevator was very sensitive, and assumed it was tail heavy, so I added weight in the nose......lots.....
It did make it fly more stable
But that caused the plane to be very light on the tail wheel, and I was concerned that it would nose over....I would not dare taxi it back after landing because it was so close to nosing over.
So I shimmed the landing gear slightly on the rear mouns to get them forward. And that solved the problem.
But after flying the plane alot more, I have removed alot of the nose weight again, and reduced elevator throw, and put some expo on it too.
The plane now flys more neutral. But I do have some down elevator for level flying.
Going to do some more dive test with the motor at idle to see if I need more down thrust on my engine, as I feel the CG is realy good now.
But now, when flying level, and I chop the throttle, the plane does not seem to change attitude....
So it is up to where you have the CG.
But I would say it is fine as it is. you can always change it later on.
12-14-2016, 10:34 PM
#94
Join Date: Oct 2016
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Hi Kim,
I have the same kit of LA-7 and think about exactly the same mod on landing gear.
Which length of leg did you fix ? Same than on the David Andersen drawing ? Close to 300 mm if I remember well.
Is your LA-7 still flying ?
Thanks
Olivier
I have the same kit of LA-7 and think about exactly the same mod on landing gear.
Which length of leg did you fix ? Same than on the David Andersen drawing ? Close to 300 mm if I remember well.
Is your LA-7 still flying ?
Thanks
Olivier
12-18-2016, 01:24 AM
#96
Join Date: Oct 2016
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Thanks.
I have the Electron retract with 85 degree blocks. I didn't get the kit with stock struts.
I will probably machine my own struts.
I plan to install an old radial Seidel ST 7-70 and I will aslo to build it as light weight as possible...
I have the Electron retract with 85 degree blocks. I didn't get the kit with stock struts.
I will probably machine my own struts.
I plan to install an old radial Seidel ST 7-70 and I will aslo to build it as light weight as possible...
12-19-2016, 10:01 AM
#100
Not completely sure. I used 90 degree in mine. however I don't see why 85 degree wouldn't work. mine seem to be toed out.
Here are pics of my la7 and my cy bf109.also getting ready to start the 96" p51 in miss america dress.
We also sell the cy line up. what i do is test a model they offer and suggest minor improvments, check them for overall performance and quality, then market them. I did do a build thread also on the yak3u. it was a wonderful flying airplane.
Here are pics of my la7 and my cy bf109.also getting ready to start the 96" p51 in miss america dress.
We also sell the cy line up. what i do is test a model they offer and suggest minor improvments, check them for overall performance and quality, then market them. I did do a build thread also on the yak3u. it was a wonderful flying airplane.
Last edited by taildragger21; 12-19-2016 at 10:04 AM.