adding flaps to an arf
08-24-2008, 05:23 PM
#101
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RE: adding flaps to an arf
Hey gents, excellent info. I just recently purchased a Hanger 9 .60 ARF F4U Corsair. I really want to put flaps on this thing and wanted to know if you guys have you any tips before I start cutting or if you have seen any other forums talking about modifying a .60 ARF Corsair?
Thanks
Thanks
08-25-2008, 11:31 AM
#105
RE: adding flaps to an arf
I would look at connecting the servo to the center flap to avoid any excessive binding forces. I would have planed out how to tie the three flap together. I’ve thought about doing this many times since I lost my Zeroli, but the retracts available for this size model are poor at best so I just watch for now. I’ve been considering if building a nyrod into the center flap and then drilling a hole in the ones it mates up with for the nyrod to go through and hardening the hole with CA would do the trick. It fits KISS real well, my main concern is the flexibility may be too much.
Also there is not a lot of room there for a servo so I would look for room mounting the servo in the wheel well and putting a concealed control horn inside the wing on the top of the center flap. That should keep all the linkages and retracts from tangling together.
Good luck, please post your progress here I’m interested to see how it works out.
Joe
Also there is not a lot of room there for a servo so I would look for room mounting the servo in the wheel well and putting a concealed control horn inside the wing on the top of the center flap. That should keep all the linkages and retracts from tangling together.
Good luck, please post your progress here I’m interested to see how it works out.
Joe
08-26-2008, 04:06 AM
#106
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RE: adding flaps to an arf
Ok just kidding , I have my second one new in box .
Plan -1)cutting flaps from wings with nife , not dremil cutting tool , while dremil is great it will create a gap and I want to see how much of the original wing/flap I can use .
2)plan on tapeing my area off taht will be cut keeping the flap 100% solid until removed from wing
3)would like to keep the servos ahead of the cg , that will keep the average of 1.2 oz per servo =2.5 to 3oz ahead of CG , important considering wheels impact CG when retracted .
4)I am going to evalute two options , 1)one HD servos driveing bell cranks similar to the original RED box Top Flight set ups and connecting to center flap as suggested or two servos -standard with center flap connection .
5)hollow out flaps in scale manner as applacable so that internal slats will slide as flaps are extended .
Plan -1)cutting flaps from wings with nife , not dremil cutting tool , while dremil is great it will create a gap and I want to see how much of the original wing/flap I can use .
2)plan on tapeing my area off taht will be cut keeping the flap 100% solid until removed from wing
3)would like to keep the servos ahead of the cg , that will keep the average of 1.2 oz per servo =2.5 to 3oz ahead of CG , important considering wheels impact CG when retracted .
4)I am going to evalute two options , 1)one HD servos driveing bell cranks similar to the original RED box Top Flight set ups and connecting to center flap as suggested or two servos -standard with center flap connection .
5)hollow out flaps in scale manner as applacable so that internal slats will slide as flaps are extended .
11-03-2008, 12:57 PM
#107
RE: adding flaps to an arf
Well my evergreen p-51d has 30hr of airtime on it and is really showing its age. I’ve stripped it of all covering and found a couple of things I want to comment on.
First – I believe the plane was covered with ultra coat, at least I bought a role of silver/grey/aluminum (SAG, what ever they called) it and it matched exactly. The SAG would curl at the tips al the time to the point I put a strip across the LE, TE, and wing tip to stop it. Then after a while the strip started to curl so when that got bad enough I removed it and layed another fresh strip down. While all this was going on with the SAG the yellow required no maintenance at all, No curling, no tears, no pulled seams. But the most important thing I noticed is that when I removed the covering I got no separation. When removing 4+ year old monokote quite often the color portion of the covering stays with the plane and only the clear Mylar sheet peals up. This would require sanding and/or solvents to remove if a lighter color is going over it. But non of that here! The SAG showed no UV imbritlement while the yellow did on the top side covering.
I knew the right H. stab LE had broken several times I had re-glued it by ironing the covering on the bottom of the stab right to the LE then removing a small sliver right over the crack and filling that with thin CA and let it wick into the wood each time it broke. It turned out that the TE was also broken and as soon as the covering was removed the stab came apart. The wood is really punky and not what I would have picked for a structural member. I still have not decided how to handle this because I do not want to remove the empennage.
The canopy had cracked several times. And deformed very badly from UV light as well. I wrote raiden about replacing the cowl and canopy but have never herd back. So I purchased a flop tite p-40 canopy to turn this into a B, then found the flop tite p-51d to b conversion kit. Oh well.
We have a lot of fuel soaking also.
I’ll post some pic’s when I get them.
Joe
First – I believe the plane was covered with ultra coat, at least I bought a role of silver/grey/aluminum (SAG, what ever they called) it and it matched exactly. The SAG would curl at the tips al the time to the point I put a strip across the LE, TE, and wing tip to stop it. Then after a while the strip started to curl so when that got bad enough I removed it and layed another fresh strip down. While all this was going on with the SAG the yellow required no maintenance at all, No curling, no tears, no pulled seams. But the most important thing I noticed is that when I removed the covering I got no separation. When removing 4+ year old monokote quite often the color portion of the covering stays with the plane and only the clear Mylar sheet peals up. This would require sanding and/or solvents to remove if a lighter color is going over it. But non of that here! The SAG showed no UV imbritlement while the yellow did on the top side covering.
I knew the right H. stab LE had broken several times I had re-glued it by ironing the covering on the bottom of the stab right to the LE then removing a small sliver right over the crack and filling that with thin CA and let it wick into the wood each time it broke. It turned out that the TE was also broken and as soon as the covering was removed the stab came apart. The wood is really punky and not what I would have picked for a structural member. I still have not decided how to handle this because I do not want to remove the empennage.
The canopy had cracked several times. And deformed very badly from UV light as well. I wrote raiden about replacing the cowl and canopy but have never herd back. So I purchased a flop tite p-40 canopy to turn this into a B, then found the flop tite p-51d to b conversion kit. Oh well.
We have a lot of fuel soaking also.
I’ll post some pic’s when I get them.
Joe
..
06-23-2009, 01:56 PM
#110
RE: adding flaps to an arf
Putting flaps on that would use the same process as laid out here, just with more fixturing up front. You have a very thin TE and strip ailerons so you will need to increase the width (LE to TE of the control surface). So first you need to calculate the amount of aileron you have on one panel (length times width). Take 70% of that number (for the new ailerons, you can go to 100% of the strip area but that will give a really snappy aileron) and draw the ailerons and flaps on the wing with a felt tip marker. When you have it drawn so that you like it then draw the U channel TE in place. You will need at least ½ inch sheeting to support the added stress. This will tell you where you have to put the ¼ in square balsa crutch. The crutch is CA’ed to the top and bottom of the wing to keep everything the same while you work on the wing. You obviously want it out of your way when working so it has to be at lease ¼ in away from the sheeting. I don’t think it will leave a lot of the original covering. But from that point on you will have to make new ailerons, flaps, servo mounts for each and the new TE.
Joe
Joe
02-08-2013, 12:19 PM
#114
RE: adding flaps to an arf
2010 I converted it to electric, I used:
Turnagy 5065-350 turning an 16x10 APC-e
Opto – 120A
8s5k20c batteries
This setup worked very well, I used battery placement to get the same CG. With a standard setup, not a pumped engine, you would have to move the CG forward to account for the unburned fuel in the tank after you land. I usually start at .25in forward.
I flew it that way till july of 2011 when at Gilbertsville for one of their Flyin’s it took off with a ton of right aileron so I went high to retrim. Once happy with it, about a minute later, I tried a high down wind full bore pass. Everything was good. Throttled back to half rolled into a split – S and came out on the field for a low full power pass. When I reached full power the plane did not acknowledge. I still had all other controls but no T, and I was hot, so I needed to bleed off speed so I climbed to 20ft as it passed me. That’s when I, and everyone else, noticed the smoke billowing out of the cowl. Well I can’t justify keeping it over the runway so I did a 180 degree turn and landed just off the runway, clean. Once the plane came to rest it continued to smoke as we walked out to it, what ever was burning stopped by the time we got there but it smelled like a electrical fire so I stripped all the electronics off. So I stuffed it in the shed and forgot about it for months. Looked at the components and they all failed, the motor turned like all the leads were grounded together, and the speed control was on fire enough to burn most of the red soldier making away and ash most of the components.
Then one day in the winter I brought it in, it no longer stank, so I stated fitting new motor and speed control to it:
Turnagy 5065-380 that I just replaced the shaft on thinking it was bent.
Dlux 80A and 15x8 APC-e
That setup flew great till the end of June 2012 when I had to remove the true turn spinner to keep it from going ape at full throttle. Then as the time went by it would get picky at full throttle without the spinner. So I tore it down. Found that the die cast turnagy engine mount had cracked, once replaced I put 5 flights on it in nov without the spinner. March or april will be the first flight with the spinner. Even with all the problems it is up to 45hr of air time.
Joe
Turnagy 5065-350 turning an 16x10 APC-e
Opto – 120A
8s5k20c batteries
This setup worked very well, I used battery placement to get the same CG. With a standard setup, not a pumped engine, you would have to move the CG forward to account for the unburned fuel in the tank after you land. I usually start at .25in forward.
I flew it that way till july of 2011 when at Gilbertsville for one of their Flyin’s it took off with a ton of right aileron so I went high to retrim. Once happy with it, about a minute later, I tried a high down wind full bore pass. Everything was good. Throttled back to half rolled into a split – S and came out on the field for a low full power pass. When I reached full power the plane did not acknowledge. I still had all other controls but no T, and I was hot, so I needed to bleed off speed so I climbed to 20ft as it passed me. That’s when I, and everyone else, noticed the smoke billowing out of the cowl. Well I can’t justify keeping it over the runway so I did a 180 degree turn and landed just off the runway, clean. Once the plane came to rest it continued to smoke as we walked out to it, what ever was burning stopped by the time we got there but it smelled like a electrical fire so I stripped all the electronics off. So I stuffed it in the shed and forgot about it for months. Looked at the components and they all failed, the motor turned like all the leads were grounded together, and the speed control was on fire enough to burn most of the red soldier making away and ash most of the components.
Then one day in the winter I brought it in, it no longer stank, so I stated fitting new motor and speed control to it:
Turnagy 5065-380 that I just replaced the shaft on thinking it was bent.
Dlux 80A and 15x8 APC-e
That setup flew great till the end of June 2012 when I had to remove the true turn spinner to keep it from going ape at full throttle. Then as the time went by it would get picky at full throttle without the spinner. So I tore it down. Found that the die cast turnagy engine mount had cracked, once replaced I put 5 flights on it in nov without the spinner. March or april will be the first flight with the spinner. Even with all the problems it is up to 45hr of air time.
Joe
03-22-2013, 04:44 PM
#115
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RE: adding flaps to an arf
Joe,
Ran across your very informative thread while searching a way to add flaps to my Seagull PC-9 120 size. Took your advice and made the cut just now. Going to pick up some hinges over the weekend.
Thanks for the valuable info.
Ran across your very informative thread while searching a way to add flaps to my Seagull PC-9 120 size. Took your advice and made the cut just now. Going to pick up some hinges over the weekend.
Thanks for the valuable info.
03-25-2013, 02:48 PM
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RE: adding flaps to an arf
If the trailing edge of the wing is a plywood secondary spar (see photo), can the robart hinges be installed directly? Or do I still need to glue a piece of balsa block behind it? I can't really get access to the inside of wing unless I start cutting into the sheeting.
03-26-2013, 08:35 AM
#118
RE: adding flaps to an arf
Steph,
So you can understand what’s going on here. On a War Bird it is common to land with 45-50 degrees of flap. If you pop it down at full tilt hopefully your servo will stall. If it does not you will damage the flap system or the plane just from the amount or energy involved. This can be anything from breaking the epoxy free on one or more hinges ( most common) to the flap coming off the plane (never sean, but read about). So we slow to 60mph then feed in the flap to reduce the stress on the system. The most common form of initial failure is hinge loosening up on one side (breaking free of the bond), I usually fix that with a drop of CA.
So will the ply alone work? Yes. But…
- First I would screw a sheet metal screw into one side of the ply where I can rap something around it to remove it. Then cut all the sides as free as I can with a sharp x-acto. Then use the screw to pull it out of place. If that proves to be to difficult, there is something else attached to it behind it, I would repair all cuts with CA. and continue on.
- If it comes out install the balsa blocks and button it back up with CA.
- If it does not come out I would look for ways to support the hinge by more than just the ply. One of my favorite tricks is to install the hinge point right on the side of a rib. Then when the hinge is installed drill a hole in the ply to add epoxy to hold the hinge point to the rib. Then foam the area after that. I use two part boat foam, but the rattle can house insulation foam is cheaper and more structural.
Without the balsa you have to use epoxy to fix loose hinges which will cause a lot more work. an ounce of prevention here beats having to diddle with it for ever.
Joe
So you can understand what’s going on here. On a War Bird it is common to land with 45-50 degrees of flap. If you pop it down at full tilt hopefully your servo will stall. If it does not you will damage the flap system or the plane just from the amount or energy involved. This can be anything from breaking the epoxy free on one or more hinges ( most common) to the flap coming off the plane (never sean, but read about). So we slow to 60mph then feed in the flap to reduce the stress on the system. The most common form of initial failure is hinge loosening up on one side (breaking free of the bond), I usually fix that with a drop of CA.
So will the ply alone work? Yes. But…
- First I would screw a sheet metal screw into one side of the ply where I can rap something around it to remove it. Then cut all the sides as free as I can with a sharp x-acto. Then use the screw to pull it out of place. If that proves to be to difficult, there is something else attached to it behind it, I would repair all cuts with CA. and continue on.
- If it comes out install the balsa blocks and button it back up with CA.
- If it does not come out I would look for ways to support the hinge by more than just the ply. One of my favorite tricks is to install the hinge point right on the side of a rib. Then when the hinge is installed drill a hole in the ply to add epoxy to hold the hinge point to the rib. Then foam the area after that. I use two part boat foam, but the rattle can house insulation foam is cheaper and more structural.
Without the balsa you have to use epoxy to fix loose hinges which will cause a lot more work. an ounce of prevention here beats having to diddle with it for ever.
Joe
03-26-2013, 09:39 AM
#119
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RE: adding flaps to an arf
Joe,
Thanks for your very thorough explanation. Based on the heavy wing loading and streamline shape of this plane, I think I better not take a chance with a mediocre flaps job. I checked the wing root and may be able to squeeze a couple balsa blocks in there. I was thinking of using a long music wire to position it, but do you have any other tricks to do this?
Based on what you say, it looks like I will need a pretty heavy duty servo for the flaps as well. Would something with similar torque as aileron servos work, or does it need more sturdy servos?
Thanks again.
Stephen
Thanks for your very thorough explanation. Based on the heavy wing loading and streamline shape of this plane, I think I better not take a chance with a mediocre flaps job. I checked the wing root and may be able to squeeze a couple balsa blocks in there. I was thinking of using a long music wire to position it, but do you have any other tricks to do this?
Based on what you say, it looks like I will need a pretty heavy duty servo for the flaps as well. Would something with similar torque as aileron servos work, or does it need more sturdy servos?
Thanks again.
Stephen
03-27-2013, 04:53 AM
#120
RE: adding flaps to an arf
Steph, for servo torque calculations I go to here:
http://mnbigbirds.com/Servo%20Torque%20Caculator.htm
IDK what your control surface dimensions are but the max surface deflection is 45 and 50 degrees. The max servo deflection is 60 degrees. I do the calculation for all the speeds I think the plane can do so I know what the affect of to much speed when I deploy will be (because we always make mistakes).
To do your other surfaces:
Surface max. movement will be between 10 and 20 degrees. Max servo movement on a servo will be 30 degrees. Just as examples, so you can see the stress on your other surfaces/servos.
My rule of thumb is A,E,R 1.5x what this shows if run by two servos, 2x if run by 1. Flaps are best fit and be mind full of when you are close to stalling the servo.
Joe
http://mnbigbirds.com/Servo%20Torque%20Caculator.htm
IDK what your control surface dimensions are but the max surface deflection is 45 and 50 degrees. The max servo deflection is 60 degrees. I do the calculation for all the speeds I think the plane can do so I know what the affect of to much speed when I deploy will be (because we always make mistakes).
To do your other surfaces:
Surface max. movement will be between 10 and 20 degrees. Max servo movement on a servo will be 30 degrees. Just as examples, so you can see the stress on your other surfaces/servos.
My rule of thumb is A,E,R 1.5x what this shows if run by two servos, 2x if run by 1. Flaps are best fit and be mind full of when you are close to stalling the servo.
Joe
03-28-2013, 07:22 PM
#121
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RE: adding flaps to an arf
Ok I finished my first flaps conversion. I didn't have any matching red ultracote so I used the white Monokote I had laying around. It's not the prettiest conversion, but functionally it's 100%. Thanks again to Joe for your detailed instructions!
03-29-2013, 06:41 AM
#122
RE: adding flaps to an arf
Steph, your not done yet.
Those control horns are … well … junk. The screw is in the middle of the bearing surface (not a good location for positive control) so over time the wood in the attachment point and the plastic in the control horn will deform allowing it to rock. Then your controls start to get mushy. You can put a screw in the front and back of that horn to prevent this but before you do that take a look at my post #17 specifically the placement of the control horn. Notice it is a ½ inch back from the L.E. of the flap that gives more movement of the flap and better control. You can accomplish this by turning your horns so they look backwards.
Joe
Those control horns are … well … junk. The screw is in the middle of the bearing surface (not a good location for positive control) so over time the wood in the attachment point and the plastic in the control horn will deform allowing it to rock. Then your controls start to get mushy. You can put a screw in the front and back of that horn to prevent this but before you do that take a look at my post #17 specifically the placement of the control horn. Notice it is a ½ inch back from the L.E. of the flap that gives more movement of the flap and better control. You can accomplish this by turning your horns so they look backwards.
Joe
03-29-2013, 06:53 AM
#123
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RE: adding flaps to an arf
Joe,
Yes I did remember seeing your post about that. I was in a hurry and not only did I forget this valuable tip, I also mounted the servos opposite to each other (like aileron), so I will need to reverse one of them. [:@]
The ply I put inside is big enough so I should be able to move the horn back without issues.
BTW those Robart pin hinges were difficult to source locally. Had to drive to 3 different hobby shops before finding some. Too bad there aren't many builders around to keep the demand up.
Thanks again.
Yes I did remember seeing your post about that. I was in a hurry and not only did I forget this valuable tip, I also mounted the servos opposite to each other (like aileron), so I will need to reverse one of them. [:@]
The ply I put inside is big enough so I should be able to move the horn back without issues.
BTW those Robart pin hinges were difficult to source locally. Had to drive to 3 different hobby shops before finding some. Too bad there aren't many builders around to keep the demand up.
Thanks again.
04-03-2020, 10:10 PM
#124
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this is a ancient thread but deserves another look, it inspired me to buy the Marie by H-9 and do some basic mods to it before taking a major break from the hobby due to Personal issues.
I recently acquired another H-9 Marie 60 completely stock and in really decent shape from my initial inspection, stock wing is in great shape and I may mate it with my original fuse for a completely stock air frame powered by a OS 91 Surpass, part of my intro back into the hobby.
It came with a Saito 91, which I am not really all that thrilled with because I am not familiar with this engine we shall see I'm more of a OS guy,my plan is to replace it with a OS 120 pumped engine,do the paladin flap mod on my original Marie wing that I have electric retracts and wheel wells already installed on, and convert this new Fuse to a P-51 C Malcolm hood version which is my favorite Mustang version.
I happen to have a Topflite P-51B conversion kit I will clone,just got some new blades for the scroll saw, and a awesome P-51 C canopy I got years ago that's been in my stash just waiting to be used thanks to a RC Universe builder.
I know Bobby had a mod thread way back for his clone conversion.
I have yet to fully inspect and break down the fuse for oil damage, but it looks good so far, further inspection is needed for sure I will use a methodical approach and point out any weaknesses in construction and my solutions.
another plan is to relocate the not so scale tail wheel to a semi-scale location I did this to my original Marie and the look is a huge improvement , not sure but I might even do a retractable tail wheel but this requires some major work, we shall see how motivated I get,
I also want to do some mods to the tail feathers as I rebuild the turtle deck some more scale bits, hopefully this inspires to unpack this great flying model and get it in the air after we all get through this nasty virus situation, Be well and stay healthy while we deal with this situation.
please chime in this thread already has some really cool information and mods.
I recently acquired another H-9 Marie 60 completely stock and in really decent shape from my initial inspection, stock wing is in great shape and I may mate it with my original fuse for a completely stock air frame powered by a OS 91 Surpass, part of my intro back into the hobby.
It came with a Saito 91, which I am not really all that thrilled with because I am not familiar with this engine we shall see I'm more of a OS guy,my plan is to replace it with a OS 120 pumped engine,do the paladin flap mod on my original Marie wing that I have electric retracts and wheel wells already installed on, and convert this new Fuse to a P-51 C Malcolm hood version which is my favorite Mustang version.
I happen to have a Topflite P-51B conversion kit I will clone,just got some new blades for the scroll saw, and a awesome P-51 C canopy I got years ago that's been in my stash just waiting to be used thanks to a RC Universe builder.
I know Bobby had a mod thread way back for his clone conversion.
I have yet to fully inspect and break down the fuse for oil damage, but it looks good so far, further inspection is needed for sure I will use a methodical approach and point out any weaknesses in construction and my solutions.
another plan is to relocate the not so scale tail wheel to a semi-scale location I did this to my original Marie and the look is a huge improvement , not sure but I might even do a retractable tail wheel but this requires some major work, we shall see how motivated I get,
I also want to do some mods to the tail feathers as I rebuild the turtle deck some more scale bits, hopefully this inspires to unpack this great flying model and get it in the air after we all get through this nasty virus situation, Be well and stay healthy while we deal with this situation.
please chime in this thread already has some really cool information and mods.
04-06-2020, 07:43 AM
#125
hi bigtime, and welcome! my p-51 in posts 112 & 113 I finally gave up on. it was being used to test rebuilt motors and I put a motor my son said would run just long enough to complete the upwind turn on takeoff. that's exactly what it did, I got it back to the runway and landed gear up. everything was fine till we walked up on it and saw the wings all laying on the runway (no dihedral). the plane was well soaked in oil and the ribs had been vibrating apart with the grain for years. when I recovered it I put cross grain supports on the ribs in front and aft of the main spar (where I could) but in the wheels up landing the balsa between the main spars was gone and the spars where free in that box. so I retired it.
mine also had a os 1.2 pumped I had bought in the 1980's maybe early 90 and spent the majority of its life in it. it had the pump fail and I could not get parts for it. hope they improved that! I finally put after market pump on it and continued on till I got out of liquid fuel.
I always liked the marie, it was a great beginner wood warbird once it had flaps. my son found a said to be h9 marie with flaps but when we unboxed it it was built even lighter than mine photos earlier so it just sits and festers in his attic. keep us apprised of your progress please.
Joe
mine also had a os 1.2 pumped I had bought in the 1980's maybe early 90 and spent the majority of its life in it. it had the pump fail and I could not get parts for it. hope they improved that! I finally put after market pump on it and continued on till I got out of liquid fuel.
I always liked the marie, it was a great beginner wood warbird once it had flaps. my son found a said to be h9 marie with flaps but when we unboxed it it was built even lighter than mine photos earlier so it just sits and festers in his attic. keep us apprised of your progress please.
Joe