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Old Jan 18, 2013, 07:42 AM
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Thanks, At the moment the turbine thrust is exactly parallel to the datum line of the fuse so no inclination at all, again showing my ignorance of turbine builds, do you think it should have a degree of inclination?
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Old Jan 18, 2013, 11:01 AM
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judging by the fact that full size has 3 degrees of incidence on the main wing and zero on the tail I am personally looking to put some down thrust in to compensate for it as a start 2 degrees. I will look at being able to adjust if necessary considering the length of jet pipe, like you this will be my first scratch built jet .In the past I have had to put down thrust on turbines to trim my Jets but with a turbine and a short pipe its easy. It keeps the old gray matter working
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Old Jan 18, 2013, 05:38 PM
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wing and tail should be 00 degrees, with a tail pipe that long you wont need to or really be able to put any down thrust, The tail pipe in the one i built was 950mm long.

Heli_madken that thrust line is perfect for the strikemaster.
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Old Jan 19, 2013, 05:01 AM
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I have checked my documentation and the wing root incidence on the full size was 3 degrees and 0 at the tip giving in effect 3 degrees of washout, I agree with you if you set the model at 0 degrees at the root the thrust line will be the same, 0. where as I am looking to build mine to the original 3 degrees it will effect the thrust line. Thinking on the full size and looking at drawings the turbine would of been quite central in the air-frame due to its size hence the thrust line angle, and wing incidence. As I see it the only difference will be the angle of attack the aircraft flies at but then taking into account the non scale weight differences between the model & full size this would change things, possibly to eliminate the wing root incidence on the model. You have me now doubting building to true scale in these areas. This is what forums are for.
Quote from Skytamer .com "Dihedral 6, Incidence 3 at root, 0: at tip. All-metal structure, with main and
subsidiary spars, having three-point attachment to fuselage. Metal-covered
ailerons ..."
cheers Dave
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Old Jan 19, 2013, 06:52 PM
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Well put it this way, the strikemasters we have built are 0 degrees at the root and are using a 1/4" of washout at the tip. Thrustline is as pictured above and the aircraft required no more than a couple clicks of trim.

Dont over think this, keep it simple.
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Old Feb 17, 2013, 03:20 AM
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Hi all, how are things progressing, I have decided to scale down my plans to 1/6 to use a spare Wren 70 I have and because of restrictions where I fly. Total change of plan for the build using foam core 3 piece wings for speed of build and a semi scale fuzz to start with to test fly. Then possibly a scale molded fuzz & built up wings in the future.
Wing span 1871 mm and 1711 mm long which will be far more manageable. I should get the wing panels in a couple of weeks.
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Old Feb 17, 2013, 02:16 PM
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SDF
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Hi, Machine Man. That's still a good size. How are you changing the fuse from scale? I think the three piece foam wing will be fine. No need for a molded wing at that scale.

Will
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Old Feb 17, 2013, 03:06 PM
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Provost

Work on mine started about a year ago, all the the CAD/CAM work on the formers wings etc are complete.
Work has started on the Plug for the fuselage which will be made using epoxy composites. Same as my other Thorjet kits, Its a 6ft wingspan version for Wren 70 or similar turbine.

The wings are 2 piece foam (Plug in) to the composite wing stubs, tailplane and fin is foam. All formers will be supplied CNC cut. Also supplied with Canopy and instructions etc.

File below was early drawings for the positioning of the turbine.
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Old Feb 17, 2013, 03:20 PM
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Hi will, I intend to build the fuzz with scale length & width etc but make it a bit more boxlike for ease of build. I want it to look something like the outline but simple in construction, big hatches & easily repaired for those senior moments on landing and of course fun to fly without worrying about cost & time spent building.

MM
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Old Feb 17, 2013, 03:35 PM
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Thorjet, looks great, now I know where to go for a more scale fuzz in future. As I posted before I am not too keen on a 2 piece wing because the wing is so low in the fuzz and with 6 degrees of dihedral its a problem getting a tube through and the wheel wells don't help, I like Kens idea with two spars, one either side of the wheel well, these will work great with foam wings. I will be designing a scale retract set soon, will keep you posted.

MM
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Old Feb 17, 2013, 04:52 PM
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MM

Retracts sound great, that is one area I don't have a lot of time to deal with due to all the work on the airframes. Will keep you updated on the fuzz.

Russ
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Old Feb 23, 2013, 04:05 AM
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I have been busy getting things together, wings ordered, retracts started tires for wheels arrived and fuzz under design. I have been looking at the thrust line & incidences again and through a mate who worked on JP's I have decided to go with the 3 degrees of incidence on both wing & tail with the same thrust line. This will give a slight nose down attitude when flying which I am told is correct, it also gives more room around the turbine and does not interfere with the wing. Another mate is making a pair of conformal tanks to suit , thrust tube to be a max of 890 mm long. This may shorten when we finalize the turbine position after balancing. Pic of layout being set up on the profile showing wing incidence and proposed turbine position.
Hows your coming along Ken.

MM
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Old Mar 10, 2013, 04:49 AM
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My Jet pipe arrived yesterday so I can finalize the fuzz design, not got my wing yet.The retract units are nearing completion then onto the oleo's. How is your build coming along Ken.
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Old Mar 13, 2013, 02:59 PM
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Looks great! Get working on it and show some pictures!
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Old Mar 17, 2013, 12:11 AM
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Work on mine continues. Getting closer to something I can mill in my CNC machine.
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