Scat-Cat 1st flight(s)
02-14-2004, 10:23 AM
#26
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RE: Scat-Cat 1st flight(s)
Daven,
I'm surprised to hear the Fuse on the Viper is narrower than the Scat. The Scat Fuse is the minimum allowed with respect to width, height, & cross sectional area for the Q500 Rules as of 20 years ago. I guess they changed the rules. A little over 90 sounds right with a 25SX. The Combo I sent to Razor was radared at 146 MPH, 20 years ago.
Q-Ball
1) Build it light, The Scats I raced in Q-500 were right at the minimum allowed 3.5# Razors is a little more than that with the 7.5 & Pipe
2) Forget the rudder and shape the empannage and wingtips like Razors, Trailing edges sharp and Leading edges > .050" Radius.
3)Make sure Engine Thrust Line, Wing, & Horiz Stab Incidence are all at 0 degrees. I used a small amount of Vert Stab offset for pylon racing but suggest you put it on straight for a sport plane.
4) Setup with CG 2.4" behind LE. Set Aileron total throw at .330" and Elevator at .750 use exponential with thes settings. If you use linear reduce the Elevator throw to .600"
5) Get a Foremost Airflo 40 engine mount. These are still listed on Sheldons Website for $7.50. Fair the mount into the fuse.
6) Use some of that airfoil shaped fairing on the gear struts and use 2.25" O-ring racing wheels.
Have Fun and send us photos!
I'm surprised to hear the Fuse on the Viper is narrower than the Scat. The Scat Fuse is the minimum allowed with respect to width, height, & cross sectional area for the Q500 Rules as of 20 years ago. I guess they changed the rules. A little over 90 sounds right with a 25SX. The Combo I sent to Razor was radared at 146 MPH, 20 years ago.
Q-Ball
1) Build it light, The Scats I raced in Q-500 were right at the minimum allowed 3.5# Razors is a little more than that with the 7.5 & Pipe
2) Forget the rudder and shape the empannage and wingtips like Razors, Trailing edges sharp and Leading edges > .050" Radius.
3)Make sure Engine Thrust Line, Wing, & Horiz Stab Incidence are all at 0 degrees. I used a small amount of Vert Stab offset for pylon racing but suggest you put it on straight for a sport plane.
4) Setup with CG 2.4" behind LE. Set Aileron total throw at .330" and Elevator at .750 use exponential with thes settings. If you use linear reduce the Elevator throw to .600"
5) Get a Foremost Airflo 40 engine mount. These are still listed on Sheldons Website for $7.50. Fair the mount into the fuse.
6) Use some of that airfoil shaped fairing on the gear struts and use 2.25" O-ring racing wheels.
Have Fun and send us photos!
02-14-2004, 02:59 PM
#27
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RE: Scat-Cat 1st flight(s)
The maximum width is the same on both planes (Roughly 2 7/8"). When I say that it is skinnier, I mean that it is tapered much more towards the nose, and towards the tail from the widest point of the fuze ( 2 7/8"). Kinda like an overstuffed guppy.
02-14-2004, 04:52 PM
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RE: Scat-Cat 1st flight(s)
Ok EW,
You'll find I ain't no rocket guy when it comes to the serious side of racers.
I was just going to build it stock.Not gonna use it for racing but looks like some of this is simple and I don't mind simple.Kinda like KISS..lOL
OK,what is empannage??
You say make the trailing edge sharp.Aileron also?
If the leading edge is to be somewhat sharp.I'll just sand it down pretty good.Till I think it's starting to look weak.
Throws: Aileron .330? What part of an inch is that? Like 3/16?,1/8?
Elevator .750? Looks like 3/4 of an inch to me...???
You say airfoil shape on the gear legs. You mean make some form of a V and glue it to the front of the strut.
Ok,get off the floor.I know it's funny,but I said I ain't no rocket scientist and math was my worse subject in the one room schoolhouse.I was out to recess when they taught arithetic.
Thanx a mil'
Walt
You'll find I ain't no rocket guy when it comes to the serious side of racers.
I was just going to build it stock.Not gonna use it for racing but looks like some of this is simple and I don't mind simple.Kinda like KISS..lOL
OK,what is empannage??
You say make the trailing edge sharp.Aileron also?
If the leading edge is to be somewhat sharp.I'll just sand it down pretty good.Till I think it's starting to look weak.
Throws: Aileron .330? What part of an inch is that? Like 3/16?,1/8?
Elevator .750? Looks like 3/4 of an inch to me...???
You say airfoil shape on the gear legs. You mean make some form of a V and glue it to the front of the strut.
Ok,get off the floor.I know it's funny,but I said I ain't no rocket scientist and math was my worse subject in the one room schoolhouse.I was out to recess when they taught arithetic.
Thanx a mil'
Walt
02-14-2004, 07:09 PM
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RE: Scat-Cat 1st flight(s)
Thats funny Q-Ball.
You got .750 correct as 3/4" so you are on the right path.
.330 is a hair under 3/8" (Which is .375")
Leading edge should be slightly rounded, but the Trailing edge can be sharp. If I remember correctly, the aileron size that they have you use is quite large. I wouldn't suggest going with anything over 12" in length (each side).
You got .750 correct as 3/4" so you are on the right path.
.330 is a hair under 3/8" (Which is .375")
Leading edge should be slightly rounded, but the Trailing edge can be sharp. If I remember correctly, the aileron size that they have you use is quite large. I wouldn't suggest going with anything over 12" in length (each side).
02-14-2004, 07:31 PM
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RE: Scat-Cat 1st flight(s)
LOL...I got that..
I've havent seen one of these close up at all,but the way your talking is that the kit comes with full length ailerons and you have to cut them to the length you want. I'll go for the 12".If you cut the ailerons short don't that mean your gonna have to use a servo for each one,whereas if you leave the ailerons full length you can use just one...Weight factor??
If I have to cut them,I'd guess that you need about four inches from the tip of the wing to where the aileron starts.Aileron 12", then a long aileron center piece (trailing edge).Rite?
I'm gettin'there.
Thanx Walt
I've havent seen one of these close up at all,but the way your talking is that the kit comes with full length ailerons and you have to cut them to the length you want. I'll go for the 12".If you cut the ailerons short don't that mean your gonna have to use a servo for each one,whereas if you leave the ailerons full length you can use just one...Weight factor??
If I have to cut them,I'd guess that you need about four inches from the tip of the wing to where the aileron starts.Aileron 12", then a long aileron center piece (trailing edge).Rite?
I'm gettin'there.
Thanx Walt
02-15-2004, 09:54 AM
#31
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RE: Scat-Cat 1st flight(s)
Q-Ball,
Daven has already answered most of your questions.
"Empannage" refers to Vertical Stabilizer, Rudder, Horizontal Stabilizer, and Elevator. Same as term "tailfeathers"
Empannage Leading edges should be small radius like a pencil lead. Trailing edges should be as sharp as you think you can get away with from a durability point of view. Thats why I inlaid harder wood on the trailing edges. What might be easier and work just as well would be to sand the balsa to a sharp TE then put some thin CA Adhesive on it to toughen up.
The aileron throws I gave you were for ailerons as shown on the original Fliteline plans. .330" is between 5/16th and 3/8th. Be sure to seal gap with Monokote.
The airfoil shape on the gear legs is just a moulded plastic piece that slips over the 1/8th music wire before you put the wheels on. It was a rubbery plastic like weatherstripping and all the hobby supply outlets used to carry it. If it is no longer available; just use a piece of balsa 1/8th triangle stock grooved to fit up against rear of 1/8th Gear. Then just put a piece of heatshrink tubing over it and shrink to form.
Hace Fun!
Daven has already answered most of your questions.
"Empannage" refers to Vertical Stabilizer, Rudder, Horizontal Stabilizer, and Elevator. Same as term "tailfeathers"
Empannage Leading edges should be small radius like a pencil lead. Trailing edges should be as sharp as you think you can get away with from a durability point of view. Thats why I inlaid harder wood on the trailing edges. What might be easier and work just as well would be to sand the balsa to a sharp TE then put some thin CA Adhesive on it to toughen up.
The aileron throws I gave you were for ailerons as shown on the original Fliteline plans. .330" is between 5/16th and 3/8th. Be sure to seal gap with Monokote.
The airfoil shape on the gear legs is just a moulded plastic piece that slips over the 1/8th music wire before you put the wheels on. It was a rubbery plastic like weatherstripping and all the hobby supply outlets used to carry it. If it is no longer available; just use a piece of balsa 1/8th triangle stock grooved to fit up against rear of 1/8th Gear. Then just put a piece of heatshrink tubing over it and shrink to form.
Hace Fun!
02-15-2004, 11:09 AM
#32
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RE: Scat-Cat 1st flight(s)
You got it exactly.
I would start the ailerons 4" from the center of the wing, and extend each of them for 12" from that point.
For sport use, you could make the ailerons a little bigger, but I definately would leave at least 6" of Trailing edge material at the outboard edges of each wing tip.
You can still use 1 servo for the ailerons with torque rods in the center.
I would start the ailerons 4" from the center of the wing, and extend each of them for 12" from that point.
For sport use, you could make the ailerons a little bigger, but I definately would leave at least 6" of Trailing edge material at the outboard edges of each wing tip.
You can still use 1 servo for the ailerons with torque rods in the center.
