Shrike 40 with thinner airfoil
12-06-2012, 08:52 PM
#77
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RE: Shrike 40 with thinner airfoil
Here is mine.
The airfoil is thinned to 8%, wingspan shortened by one rib bay, fully sheeted, carbon tube spars, fuse thinned to 1/2" above and below wing,
new fin shape, Tettra tank, quickie landing gear, small winglets, glassed and painted. Paint is PPG DBC with House of Color Ultra Mini flake at 10%.
Looks wild in the sun. I had a Jett SS .40 on it, but had to sell it any many others. Sometimes life bites!
Will soon have a TT .46 with Jett tuned muffler. Still have not flown it.
Tony
The airfoil is thinned to 8%, wingspan shortened by one rib bay, fully sheeted, carbon tube spars, fuse thinned to 1/2" above and below wing,
new fin shape, Tettra tank, quickie landing gear, small winglets, glassed and painted. Paint is PPG DBC with House of Color Ultra Mini flake at 10%.
Looks wild in the sun. I had a Jett SS .40 on it, but had to sell it any many others. Sometimes life bites!
Will soon have a TT .46 with Jett tuned muffler. Still have not flown it.
Tony
12-09-2012, 11:49 PM
#83
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RE: Shrike 40 with thinner airfoil
I never built a stock Shrike 40, so I have no idea what one might weigh.
Mine is dimensionally smaller, however, it is fully sheeted, epoxy glassed and painted.
We had a house built and have just moved in. My hobby stuff comes after we get settled in.
I'll weigh it then ad let you know. Should be after the holidays.
Thanks for the interest, I had fun with the modifications.
Tony
Mine is dimensionally smaller, however, it is fully sheeted, epoxy glassed and painted.
We had a house built and have just moved in. My hobby stuff comes after we get settled in.
I'll weigh it then ad let you know. Should be after the holidays.
Thanks for the interest, I had fun with the modifications.
Tony
12-10-2012, 12:11 PM
#84
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RE: Shrike 40 with thinner airfoil
ORIGINAL: Speedy-Gonzales
Well here are some pics of my new SHRIKE on the board.
Mods include:
Nose shortened by 1.5'' and spinner size reduced to 2'' diameter. The fuselage has also been reduced in height by 3/8'' top and bottom 3/4'' total.
As you can see I have now incorporated 3/8'' diameter CF tubes for the spars and you can see the new ribs in the picture that have been reduced in height by 40% from the original.
This is not a ''balls out'' effort but an attempt to see how the SHRIKE will perform in this configuration comparred to stock. If this works out well I will take it another step and do another build with more mods.
Oh yes....engine is a ''tweaked'' K/B 6.5 series II Q500 with mini pipe.
Should run in the 20K range on a prepped Rev-Up 8.625D x 7.0P . Nice thing about the K/B ''metrics'' is that I can drop in a tweaked 7.5cc if wanted.
Well here are some pics of my new SHRIKE on the board.
Mods include:
Nose shortened by 1.5'' and spinner size reduced to 2'' diameter. The fuselage has also been reduced in height by 3/8'' top and bottom 3/4'' total.
As you can see I have now incorporated 3/8'' diameter CF tubes for the spars and you can see the new ribs in the picture that have been reduced in height by 40% from the original.
This is not a ''balls out'' effort but an attempt to see how the SHRIKE will perform in this configuration comparred to stock. If this works out well I will take it another step and do another build with more mods.
Oh yes....engine is a ''tweaked'' K/B 6.5 series II Q500 with mini pipe.
Should run in the 20K range on a prepped Rev-Up 8.625D x 7.0P . Nice thing about the K/B ''metrics'' is that I can drop in a tweaked 7.5cc if wanted.
Yours look very good so far , please post some pics on here when you have it done.
Picture show ribs of mine , stock and after mods.
12-10-2012, 12:14 PM
#85
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RE: Shrike 40 with thinner airfoil
ORIGINAL: NoOneFlysAtMyClub
Here is mine.
The airfoil is thinned to 8%, wingspan shortened by one rib bay, fully sheeted, carbon tube spars, fuse thinned to 1/2'' above and below wing,
new fin shape, Tettra tank, quickie landing gear, small winglets, glassed and painted. Paint is PPG DBC with House of Color Ultra Mini flake at 10%.
Looks wild in the sun. I had a Jett SS .40 on it, but had to sell it any many others. Sometimes life bites!
Will soon have a TT .46 with Jett tuned muffler. Still have not flown it.
Tony
Here is mine.
The airfoil is thinned to 8%, wingspan shortened by one rib bay, fully sheeted, carbon tube spars, fuse thinned to 1/2'' above and below wing,
new fin shape, Tettra tank, quickie landing gear, small winglets, glassed and painted. Paint is PPG DBC with House of Color Ultra Mini flake at 10%.
Looks wild in the sun. I had a Jett SS .40 on it, but had to sell it any many others. Sometimes life bites!
Will soon have a TT .46 with Jett tuned muffler. Still have not flown it.
Tony
I really like the mods you did there , the paint looks GREAT too.
Can you please share more pics of yours would be great to see it from other angles.
12-10-2012, 06:11 PM
#86
My Feedback: (202)
RE: Shrike 40 with thinner airfoil
SpeedBoy,
The ribs do look very close. I know the stock thickness of the #1 rib in height before sheeting is 1-7/8". The stock wing finishes out at 2" with sheeting ( UGH!!). I wanted a finished thickness of close to 1.5" and calculated using 70% ( 0.70 ) as my multiplier. My root rib is 1-5/16" in height before sheeting. I will be sheeting the entire wing with 3/32" sheet but will be sanding at least 1/32" off to get a super smooth contoured wing with no bumps,humps, or dips. Sometimes starting with 1/16" sheet ends up being not enough. When bar sanding you can tell when the sheeting is getting too thin...it starts to bulge outward and then you have real problems.
I buy all my carbon tube from CST. I have found their materials to be the best in strightness and quality.
I'll post more pictures soon but I try to build my planes to go fast....... I do not build them fast. When you maiden a new plane and you don't need to dial in any trim.....you know you have something special and well worth the extra time to get it right.
My previous number of a 40% reduction is incorrect. 30% would be correct.
SALUTE Hombre!!!!
Speedy-Gonzales
The ribs do look very close. I know the stock thickness of the #1 rib in height before sheeting is 1-7/8". The stock wing finishes out at 2" with sheeting ( UGH!!). I wanted a finished thickness of close to 1.5" and calculated using 70% ( 0.70 ) as my multiplier. My root rib is 1-5/16" in height before sheeting. I will be sheeting the entire wing with 3/32" sheet but will be sanding at least 1/32" off to get a super smooth contoured wing with no bumps,humps, or dips. Sometimes starting with 1/16" sheet ends up being not enough. When bar sanding you can tell when the sheeting is getting too thin...it starts to bulge outward and then you have real problems.
I buy all my carbon tube from CST. I have found their materials to be the best in strightness and quality.
I'll post more pictures soon but I try to build my planes to go fast....... I do not build them fast. When you maiden a new plane and you don't need to dial in any trim.....you know you have something special and well worth the extra time to get it right.
My previous number of a 40% reduction is incorrect. 30% would be correct.
SALUTE Hombre!!!!
Speedy-Gonzales
12-13-2012, 05:09 PM
#87
My Feedback: (202)
RE: Shrike 40 with thinner airfoil
I just got to thinking about engine thrust and have a question.
Most all of my speed planes have 0-0 engine thrust. The traditional thought is to error in the direction of right and down.
OK....I'm fine with that.
Now let's consider planes that require "right and down" engine thrust to counteract torque.
When you roll inverted that "right and down" becomes "left and up" engine thrust AND the plane, if trimmed and balanced properly (and let's assume the airfoil is symetrical ), continues to fly in straight and level flight.
Comments??
Most all of my speed planes have 0-0 engine thrust. The traditional thought is to error in the direction of right and down.
OK....I'm fine with that.
Now let's consider planes that require "right and down" engine thrust to counteract torque.
When you roll inverted that "right and down" becomes "left and up" engine thrust AND the plane, if trimmed and balanced properly (and let's assume the airfoil is symetrical ), continues to fly in straight and level flight.
Comments??
12-13-2012, 08:04 PM
#88
RE: Shrike 40 with thinner airfoil
A high wing plane has the thrust mounted beneath it. If it is too far below the airframe's "vertical CG" the thrust will have an upward push on the plane, causing it to try to climb. So, the pilot has to compensate with a tiny bit of down trim....pure drag.
A low wing design with high thrust line will do the opposite. Upon hand launch these planes will tend to dive until up to flying speed.
The best speed design places the thrust line pretty much even with the airframe's "vertical CG".
The "vertical CG" is a DYNAMIC concept that takes into consideration the pitching moments that are created by aerodynamic forces in flight.
The best you can do is make a tight design, build it straight, then evaluate it after a few flights to see if the engine needs to be shimmed or not.
A low wing design with high thrust line will do the opposite. Upon hand launch these planes will tend to dive until up to flying speed.
The best speed design places the thrust line pretty much even with the airframe's "vertical CG".
The "vertical CG" is a DYNAMIC concept that takes into consideration the pitching moments that are created by aerodynamic forces in flight.
The best you can do is make a tight design, build it straight, then evaluate it after a few flights to see if the engine needs to be shimmed or not.
12-14-2012, 09:58 AM
#89
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RE: Shrike 40 with thinner airfoil
the Rossi 10MM carb neck is identical in diameter, so its a drop fit on the Picco, I have several large piccos and the 10 MM carb wakes it up! the Mac's 11CC marine pipe is the best open pipe for this setup. looks good!
12-14-2012, 11:08 AM
#90
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RE: Shrike 40 with thinner airfoil
ORIGINAL: Speedy-Gonzales
SpeedBoy,
The ribs do look very close. I know the stock thickness of the #1 rib in height before sheeting is 1-7/8''. The stock wing finishes out at 2'' with sheeting ( UGH!!). I wanted a finished thickness of close to 1.5'' and calculated using 70% ( 0.70 ) as my multiplier. My root rib is 1-5/16'' in height before sheeting. I will be sheeting the entire wing with 3/32'' sheet but will be sanding at least 1/32'' off to get a super smooth contoured wing with no bumps,humps, or dips. Sometimes starting with 1/16'' sheet ends up being not enough. When bar sanding you can tell when the sheeting is getting too thin...it starts to bulge outward and then you have real problems.
I buy all my carbon tube from CST. I have found their materials to be the best in strightness and quality.
I'll post more pictures soon but I try to build my planes to go fast....... I do not build them fast. When you maiden a new plane and you don't need to dial in any trim.....you know you have something special and well worth the extra time to get it right.
My previous number of a 40% reduction is incorrect. 30% would be correct.
SALUTE Hombre!!!!
Speedy-Gonzales
SpeedBoy,
The ribs do look very close. I know the stock thickness of the #1 rib in height before sheeting is 1-7/8''. The stock wing finishes out at 2'' with sheeting ( UGH!!). I wanted a finished thickness of close to 1.5'' and calculated using 70% ( 0.70 ) as my multiplier. My root rib is 1-5/16'' in height before sheeting. I will be sheeting the entire wing with 3/32'' sheet but will be sanding at least 1/32'' off to get a super smooth contoured wing with no bumps,humps, or dips. Sometimes starting with 1/16'' sheet ends up being not enough. When bar sanding you can tell when the sheeting is getting too thin...it starts to bulge outward and then you have real problems.
I buy all my carbon tube from CST. I have found their materials to be the best in strightness and quality.
I'll post more pictures soon but I try to build my planes to go fast....... I do not build them fast. When you maiden a new plane and you don't need to dial in any trim.....you know you have something special and well worth the extra time to get it right.
My previous number of a 40% reduction is incorrect. 30% would be correct.
SALUTE Hombre!!!!
Speedy-Gonzales
We have almost the same reduction , the rib# 1 of mine is 1-1/4" in height this is just 1/6" thinner than yours ( I reduce 5/8" from original) I think your wing and mine should behave very similar on flight.
I think the same way than you , build without any hurry , do it once but right , then when you have all the control surfaces at 0° and you airframe is flying straight and level at full throttle you know it worth the extra time you invested ,besides you dont have 2 "brakes" killing the porpose of your project ( one your incides incorrect and the other your compensation trim ) as combatpigg said pure drag.
Take your time and make it faster. [8D]
Salud mi amigo !!
12-14-2012, 12:19 PM
#91
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RE: Shrike 40 with thinner airfoil
My last 2 speed planes ( 1 "Shrike" and 1 "Screamin Demon") had an issue with harmonic feedback to the servos causing servo life to be shortened and ultimate full failure. Most often on the throttle ( no biggie ) and on the elevator. Luckily I detected the elevator failures due to erratic flight and could back off the throttle and bring it in. One such episode I was not so lucky and put my Shrike straight in at WOT. [:@]
I was left with a rebuildable engine but everything else ( and I mean everything ) was a total loss. The throttle/engine servo was INSIDE the Tetra tank! All servos were gone and the receiver was trash also. I wouldn't even consider trying to reuse any radio components after a crash like that.
Have any of you experienced problems with harmonic feedback? I have experienced it with both analog and digital servos. Hitec,JR, and Spektrum. Maybe I need to go to Hitec HS-5625's" I was told to stay away from metal gear servos with my Q500's so I have been using the JR/Spektrum DS-821's for all.
Suggestions?
I was left with a rebuildable engine but everything else ( and I mean everything ) was a total loss. The throttle/engine servo was INSIDE the Tetra tank! All servos were gone and the receiver was trash also. I wouldn't even consider trying to reuse any radio components after a crash like that.
Have any of you experienced problems with harmonic feedback? I have experienced it with both analog and digital servos. Hitec,JR, and Spektrum. Maybe I need to go to Hitec HS-5625's" I was told to stay away from metal gear servos with my Q500's so I have been using the JR/Spektrum DS-821's for all.
Suggestions?
12-14-2012, 02:07 PM
#93
RE: Shrike 40 with thinner airfoil
Nope...they are probably EZ hinges [maybe nylon "real" hinges?] that are centered in the gap. I cover the whole plane after the elevons are hinged in one fell swoop..so the gaps are sealed in one step.
I just bevel the elevon side of the gap and I do not cut much of a bevel for speed plane control surfaces that don't need much travel.
I did do skin hinges on a speed plane that hasn't flown yet. They are made from lightweight kevlar cloth.
I just bevel the elevon side of the gap and I do not cut much of a bevel for speed plane control surfaces that don't need much travel.
I did do skin hinges on a speed plane that hasn't flown yet. They are made from lightweight kevlar cloth.
12-14-2012, 03:44 PM
#94
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RE: Shrike 40 with thinner airfoil
harmonics are hell on servos, the best luck I have had is with 9000 series futaba's and now the spektrum servos... i use core-less servos where possible as they take abuse better, metal gears are fine...look at the car and buggy guys, usage mostly metal gear in the better classes, I have switched to carbon pushrods everywhere, they have soo much less mass, i still use cable with soldered ends for throttles. i like the hitec 225 servos for sport planes but they really degrade centering wise on pylon and such types of airplanes
12-14-2012, 04:54 PM
#95
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RE: Shrike 40 with thinner airfoil
Making some progress. Ribs located and secured on CF spars. the little round "washers" are to secure the ribs to the round tube spars since the original wood spars were square and the holes in the ribs are square. Decided to stay with the wood leading edges. I considered using CF tubes for the LE but I weighed them on a gram scale and comparred to the hard balsa the CF was heavier! I would not even consider using balsa main spars so if there was a weight difference it was overcome with the consideration of strength. The CF tube spars also make for a very straight wing.
I like using old flourescent light ballasts for building weights.
I learned in elementary school that the round peg will go in the square hole!
I like using old flourescent light ballasts for building weights.
I learned in elementary school that the round peg will go in the square hole!
12-14-2012, 04:57 PM
#96
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RE: Shrike 40 with thinner airfoil
My .65 Demon has "live" hinging, Fourmost premade hinged TE sections. Control seems tight and secure in the air so far, but it will take a few more flights for the longer term prognosis.
12-14-2012, 05:38 PM
#97
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RE: Shrike 40 with thinner airfoil
MJD,
You got some pics of these hinges? I'm interested in anything new or at least new to me!
Why is the "Speed Freak" forum so dead???
Hey I just thought I would mention that this is the stock K/B 6.5 that I bought off of Flyboy Dave.
I have others NIB but Dave's was the first one I pulled off the shelf.
Please don't tell him I modded the piston and sleeve from stock!! I also reworked the crank.
I'm hoping for 22K on Powermaster 10/22.
Have you done anything with the Shrike plans I sent you??
Did you tell "Santa" I want a SD kit for Christmas???
You got some pics of these hinges? I'm interested in anything new or at least new to me!
Why is the "Speed Freak" forum so dead???
Hey I just thought I would mention that this is the stock K/B 6.5 that I bought off of Flyboy Dave.
I have others NIB but Dave's was the first one I pulled off the shelf.
Please don't tell him I modded the piston and sleeve from stock!! I also reworked the crank.
I'm hoping for 22K on Powermaster 10/22.
Have you done anything with the Shrike plans I sent you??
Did you tell "Santa" I want a SD kit for Christmas???
12-15-2012, 11:58 AM
#99
My Feedback: (202)
RE: Shrike 40 with thinner airfoil
CBP,
Drop me some names for where I might find CF props in this range from custom manufacturers? I'm always concerned about throwing a blade above 22K with standard GFN APC's. I'm still running on a few 12 packs of RevUp wood pylon props and massaging them with a Prather pitch gauge.
Yeh...I've been around the block a few times but I still have a full head of hair. This old dog is still however always willing to learn new tricks.
Rain all weekend up here in N/W Ohio so I should be able to get some building time in on the Shrike.
Drop me some names for where I might find CF props in this range from custom manufacturers? I'm always concerned about throwing a blade above 22K with standard GFN APC's. I'm still running on a few 12 packs of RevUp wood pylon props and massaging them with a Prather pitch gauge.
Yeh...I've been around the block a few times but I still have a full head of hair. This old dog is still however always willing to learn new tricks.
Rain all weekend up here in N/W Ohio so I should be able to get some building time in on the Shrike.
12-15-2012, 12:13 PM
#100
RE: Shrike 40 with thinner airfoil
Steve Wilk
Eliminator Props
763-531-0604
This is the guy I use.
His props are $14 unfinished and he has filled every order of mine within 2 or 3 weeks.
He has a huge selection of old proven designs for speed planes.
Eliminator Props
763-531-0604
This is the guy I use.
His props are $14 unfinished and he has filled every order of mine within 2 or 3 weeks.
He has a huge selection of old proven designs for speed planes.