Phoenix VIII build
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Phoenix VIII build
Couple questions for you all.
1. Main landing gear location for tail dragger. The plans show tricycle gear.. We are going to do a tail dragger. Any ideas how far ahead of the CG the gear should be located?
2. Aileron servos.. We have built in "barn door" style aileron's. Wondering about concerns as to using JR 3711 HV mini servos (86 in/oz torque) out there..one each aileron of course.
3. Engine... we have a Rossi 60 side exhaust. does anyone sell piston/rod/sleeve parts for the old Rossi's? Or should I just buy a new Nova Rossi Rex engine and start fresh?
Thanks for comments..
Randy
1. Main landing gear location for tail dragger. The plans show tricycle gear.. We are going to do a tail dragger. Any ideas how far ahead of the CG the gear should be located?
2. Aileron servos.. We have built in "barn door" style aileron's. Wondering about concerns as to using JR 3711 HV mini servos (86 in/oz torque) out there..one each aileron of course.
3. Engine... we have a Rossi 60 side exhaust. does anyone sell piston/rod/sleeve parts for the old Rossi's? Or should I just buy a new Nova Rossi Rex engine and start fresh?
Thanks for comments..
Randy
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Take a profile view of the fuse with the CG position accurately shown. Position the view so that the fuse is in level flight attitude.
With the fuse in level flight attitude, draw a line straight down from the CG, then measure an arc of 15 degrees forward of the vertical line that drops down from the CG. Draw a line through the 15 degree point; locate the axle of the main gear along the line that goes through the 15 degree mark.
To get the prop clearance that you need, adjust the position of the axle along the 15 degree line.
The above works well for paved surfaces; if you will be flying from grass surface use 17 degrees instead of 15 degrees.
With the fuse in level flight attitude, draw a line straight down from the CG, then measure an arc of 15 degrees forward of the vertical line that drops down from the CG. Draw a line through the 15 degree point; locate the axle of the main gear along the line that goes through the 15 degree mark.
To get the prop clearance that you need, adjust the position of the axle along the 15 degree line.
The above works well for paved surfaces; if you will be flying from grass surface use 17 degrees instead of 15 degrees.
Last edited by Jim Oliver; 09-29-2015 at 03:18 PM. Reason: additional detail
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Hi Randy,
your aileron servos have plenty of torque! About twice as much as the servos in the original P8 (and it only had one aileron servo with torque rods). I don't think you'll find original part sot fit your Rossi and I don't know if parts from the new versions will fit, but a new R60F from SMT Distributing is only $129 which is about what you would pay for the replacement parts; so a new engine seems like a reasonable alternative. I prefer taildraggers, myself :-)
your aileron servos have plenty of torque! About twice as much as the servos in the original P8 (and it only had one aileron servo with torque rods). I don't think you'll find original part sot fit your Rossi and I don't know if parts from the new versions will fit, but a new R60F from SMT Distributing is only $129 which is about what you would pay for the replacement parts; so a new engine seems like a reasonable alternative. I prefer taildraggers, myself :-)
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Randy,
for what it's worth, the old Rossi and new NovaRossi will have the same mount pattern spacing (25 mm) and width (52 mm if memory serves). However, the crankcase length of each engine is different with the current NR's being a fair bit more compact than its other Italian predecessors.
If you are using a glass engine mount, you can swap engines by simply using two identical mounts and locating the NR further forward on the beams, or, perhaps better yet, making some 1/8" ply spacers for the engine mount when using the NR and just use the same mount.
It might be a bit of a moot point as the NR will be immeasurably more impressive than the vintage Rossi - despite Cesare being at the helm in the design of each...
David
for what it's worth, the old Rossi and new NovaRossi will have the same mount pattern spacing (25 mm) and width (52 mm if memory serves). However, the crankcase length of each engine is different with the current NR's being a fair bit more compact than its other Italian predecessors.
If you are using a glass engine mount, you can swap engines by simply using two identical mounts and locating the NR further forward on the beams, or, perhaps better yet, making some 1/8" ply spacers for the engine mount when using the NR and just use the same mount.
It might be a bit of a moot point as the NR will be immeasurably more impressive than the vintage Rossi - despite Cesare being at the helm in the design of each...
David