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Old Sep 09, 2012, 10:43 PM
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Will do- I sure appreciate the input.
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Old Sep 18, 2012, 09:51 PM
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Quick update

Just in the middle of sanding more than I ever thought possible. The horizontal stabilizer and vertical stab have been sanded to shape. Now just need to add a reinforcement bar- either CF or wooden dowel. Those of you chiming in- do you think 2 will be necessary per stabilizer? The plan was to try to embed one at midline along the leading edge. The fuselage has a while to go- a lot of sanding still to do.
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Old Sep 19, 2012, 01:17 AM
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Just in the middle of sanding more than I ever thought possible. The horizontal stabilizer and vertical stab have been sanded to shape. Now just need to add a reinforcement bar- either CF or wooden dowel. Those of you chiming in- do you think 2 will be necessary per stabilizer? The plan was to try to embed one at midline along the leading edge. The fuselage has a while to go- a lot of sanding still to do.
WOW Riebaraon Look'in GREAT! Excellent work Sir!
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Old Sep 23, 2012, 07:28 PM
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Question:

So I am in the process of sanding down the fuselage-actually starting to look good- pictures to come. I am planning to sand around the tail and leave the horizontal stabilizer attachment flat- like on the full size jet. My question is what angle of attack should I have? The stab will not be adjustable. It's not the most pressing matter right now as I am not attaching them yet but for sanding purposes it would be nice. Input from all of you pros?
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Old Sep 23, 2012, 07:53 PM
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Originally Posted by rlebaron View Post
So I am in the process of sanding down the fuselage-actually starting to look good- pictures to come. I am planning to sand around the tail and leave the horizontal stabilizer attachment flat- like on the full size jet. My question is what angle of attack should I have? The stab will not be adjustable. It's not the most pressing matter right now as I am not attaching them yet but for sanding purposes it would be nice. Input from all of you pros?
My Personal opinion Sir would be to leave the Main Stabilizer itself at a Level Horizontal angle of attack with no plus or minus leave it level with the fuselage, the reason I would do this is simple if you where to add a n"negative" angle of attack with the stab pointing down your 747 will always want to climb, and if you have a positive angle of attack with the stab pointing up she'll always want to dive.

But I'm sure everyone here on RCG has their own thoughts on this so I would not base your decision on one opinion Sir.
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Old Sep 23, 2012, 08:11 PM
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+1 the only time I have seen someone add positive AOA on the stab was to try and make a more scale approach (nose-up) and he did achieve that but at the same time the plane needed down trim the faster it went which caused drag and made the model unpleasant to fly. I wouldn't add any angle of attack.

This is just my opinion though and I think it would be worth it to hear from more people.

Ethan
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Old Sep 23, 2012, 09:22 PM
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' 0' on the H Stab and +1 or +2 degrees on the main wing, you can't go wrong with these angles.
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Old Sep 23, 2012, 09:38 PM
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Here you go with B747 cross sections, now don't worry about it being 100/200 series as most fuse cross sections will work with strategic placement through out ur fuselage. This is before you sand ur fuse by guesstimate....

http://www.rcgroups.com/forums/showt...1734624&page=4

Here are fuselage station drawings of the B747-400 and will give proper profile shape of the fuselage, vertical fin and tailcone section. Now you can accurately fix any errors in profile shape of you model.

I'm going to look for crosssection drawings of B744 or B743 for ya...
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Old Sep 23, 2012, 10:49 PM
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Originally Posted by Concordefan View Post
Here you go with B747 cross sections, now don't worry about it being 100/200 series as most fuse cross sections will work with strategic placement through out ur fuselage. This is before you sand ur fuse by guesstimate....

http://www.rcgroups.com/forums/showt...1734624&page=4

Here are fuselage station drawings of the B747-400 and will give proper profile shape of the fuselage, vertical fin and tailcone section. Now you can accurately fix any errors in profile shape of you model.

I'm going to look for crosssection drawings of B744 or B743 for ya...

So first of all thank you all for the help the on the horizontal stabs- right at 0 degrees will be the plan.

Thanks for the cross sectionals- I looked at that thread a ton but somehow missed the one thing I needed. They will definitely help at this point when I am doing the final fuselage shaping. Next will be to cut it into 3-4 sections and core it out.

Another question- Any opinions on overall finish- i.e. glassing the plane vs just the wings and stabilizers vs other options to keep things relatively light (laminate epoxy or minwax polycryilic)?
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Old Sep 24, 2012, 05:25 AM
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' 0' on the H Stab and +1 or +2 degrees on the main wing, you can't go wrong with these angles.
+1, I agree, but there is only one thing I would add to thisis the wings should have some washout built in. at least 1-2 degrees to add stability in stall mode. Like Sam pointed out 1-2 degrees positive at the root and at least the same amount but negative at the tips so the tips will be 0-deg AoA. This promotes stall at the root section of the wing instead of at the tips.

Eric B.
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Old Oct 03, 2012, 10:10 PM
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Update

So an update on some aspects of the build:

1) Wings and stabilizers. All wire cut and sanded to shape essentially. Carbon fiber rods have been embedded-need to fill in with light weight spackle. I am working on the wing box and will hopefully get the wings attached this weekend. For those of you pros- does the amount of CF seem sufficient or do I need more?
2) Fuselage- Cut into three pieces and sanded to shape based on cross sections. I am in the process of hollowing/coring out the sections.
3) Retracts and wheels are on there way- probably get trucks put together in Colorado this next week.

And thanks for the input on the stabilizer and wing angles of incidence.
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Old Oct 04, 2012, 08:32 AM
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Originally Posted by rlebaron View Post
So an update on some aspects of the build:

1) Wings and stabilizers. All wire cut and sanded to shape essentially. Carbon fiber rods have been embedded-need to fill in with light weight spackle. I am working on the wing box and will hopefully get the wings attached this weekend. For those of you pros- does the amount of CF seem sufficient or do I need more?
2) Fuselage- Cut into three pieces and sanded to shape based on cross sections. I am in the process of hollowing/coring out the sections.
3) Retracts and wheels are on there way- probably get trucks put together in Colorado this next week.

And thanks for the input on the stabilizer and wing angles of incidence.
Freak'in amazing Rlebaron!
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Old Oct 04, 2012, 08:59 AM
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Awesome Progress ... BTW nice dog..
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Old Oct 04, 2012, 02:28 PM
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Design Question

So after being up all night with a headache followed by Excedrin tension- Had some ideas for the nose and tail sections- more so just floating ideas. The tail section would essentially be the same thing as DD does on his aircraft- cutting off the lower portion so as to allow easy internal rudder and elevator servo placement, access and adjustment. I was thinking of doing the same thing in the nose section being as I have to place a retract servo and steering servo(never done this before-anticipating it to be a little tricky). Anyhow by having the bottom aspect detach I assume it would be a lot easier to set up, adjust and replace any parts should it become necessary. This section effectively just has the force from landing-nearly vertical- so I imagine it would be structurally sound with both magnets for position and 2-4 nylon bolts. Refer to image below. Any thoughts or input? Also any resources on how to attach the steering servo to a basic HK steerable retract.
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Old Oct 04, 2012, 02:45 PM
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Originally Posted by rlebaron View Post
So after being up all night with a headache followed by Excedrin tension- Had some ideas for the nose and tail sections- more so just floating ideas. The tail section would essentially be the same thing as DD does on his aircraft- cutting off the lower portion so as to allow easy internal rudder and elevator servo placement, access and adjustment. I was thinking of doing the same thing in the nose section being as I have to place a retract servo and steering servo(never done this before-anticipating it to be a little tricky). Anyhow by having the bottom aspect detach I assume it would be a lot easier to set up, adjust and replace any parts should it become necessary. This section effectively just has the force from landing-nearly vertical- so I imagine it would be structurally sound with both magnets for position and 2-4 nylon bolts. Refer to image below. Any thoughts or input? Also any resources on how to attach the steering servo to a basic HK steerable retract.

Excellent design Work Rlebaron. . . .Your teaching me some tricks as well!
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