Zephyr1's 50mm F-86 Sabre 125%

[Ranger_107]

@Zephyr1 designed this F-86 Sabre that runs off a 50mm EDF. The original build has a 32-inch wingspan and is 28 inches long. Scaled up its should be a 40-inch wingspan and is 35 inches long. I plan to run it off a 70mm BDF style ducted fan. I plan to run it of a 4s 2200mAh lipo or a 5s 3000mAh lipo. I have landed on the EMAX Eco 2207 2400kv Brushless Motor and the EMAX Formula 45A ESC. I am going to use 5-gram servos to keep the weight and cost down. I am going to put Fowler flaps and retracts. Retracts are coming from the Freewing 80mm F-86. Its an entire gear set so I wont need to get anything but that for the gear. The plans are currently being put together today. I am about halfway done with it.-

PARTS-
EDF Unit-https://www.horizonhobby.com/produc...5c30xGCBpTiAhvfW1R3KnZl441umbeqRoCMy0QAvD_BwE
ESC-https://www.racedayquads.com/produc...8ZJ5lV92Or9z6-ruQWqkBzjRRjWz061hoCb8UQAvD_BwE
Servos-https://www.racedayquads.com/products/emax-es9051-4-3g-digital-mini-servo?variant=31485582508145
Battery (4s 2200)-https://hobbyking.com/en_us/turnigy...i-jC8plix4PE42f4zGxoCxZkQAvD_BwE&gclsrc=aw.ds
Battery(5s 3000)-https://hobbyking.com/en_us/turnigy...zuu6q1axrg7o9nhNWPxoCCqYQAvD_BwE&gclsrc=aw.ds

I am going to be building this over a while and might need some help to decipher what part goes where on the plane.
Please tell me if you dont think that the parts I have chosen will work or if I will need to change some things.

Thanks for any help or advice!!
Nick aka Ranger_107.

 

[Flitedesign 3d]

I have no experience in bdfs but Im certain this plane will be way underpowered with that 2.5" prop, also that motor is meant for 5" props on 4s

 

[Ranger_107]

I have no experience in bdfs but Im certain this plane will be way underpowered with that 2.5" prop, also that motor is meant for 5" props on 4s

Wait. will a 70mm edf fit a 4 inch prop?

 

[Pieliker96]

what does a 70mm edf run?

for 4 cell, generally in the range of 2800-3600 kv, 800 to 1200 watts. That, and EDF blades are usually quite coarse in pitch (optimised for thrust at speed), the props you linked have a pitch of 4 (quite low) and are designed for the low-speed punchiness needed for miniquad flying.

The ESC you linked does not have an integrated BEC, which means you will need an external one to provide the power for the reciever and servos.

A fantastic way to reduce cost and weight is to eliminate complexity, which you've added with retracts and flaps (and their necessary supporting structure). Saving a couple grams with 5g servos but adding the weight of retracts and flaps seems like a contradiction of design philosophies. You could also reallocate funds from the retracts and/or flaps to a proper EDF unit if you don't want to go through the hassle of making a ducted prop and getting it to perform well.

Just some thoughts.

 

[Zephyr1]

Ok,

So a couple things. I love, love, love your enthusiasm for building the Sabre. It is an amazing plane and if it's not overloaded, you'll love it.

1 - 70mm = 2.75 inches. A 4 inch BDF, which is the smallest size at which it is feasible (excluding gremlin sized like Ben's B-52) is a 100mm fan.
2 - 5g servos on a jet this heavy, especially for the elevators is very under-strengthed. If you get going fast, you'll loose elevator authority and crash. I highly recommend 9g servos.
3 - Landing gear is an unnecessary addition. Flaps will work great, but i highly recommend ditching the gear.
4 - Please, please, please, look at my 70mm Sabre plans and if you don't want to deal with their added complexity, that's fine. But please use that elevator. The elevators for the 50mm Sabre are weak but workable. For a 70mm edf, they need to be heavily reinforced and all in one piece. Like this:

5- Lastly, I get wanting to do retracts and making this look great. I fully plan on returning to this jet and using a 90mm edf on 6s, adding flaps, and added the very same landing gear you are planning on using. But it will have been my 4th large Sabre. For your first Sabre, reduce complexity and make this as simple as you can, especially if your newer to jets.

 

[Ranger_107]

Thanks. I chose to do the 50mm because of its simplicity and had already looked at the 70mm Sabre and decided not to do it.
Yea. I decided to ditch the gear because it was going to be too much of hassle. Will a 100mm fan even work with a scaled-up design? for reference the scaled-up would be made for a 65mm edf I think I just realized that the fan files i had were actually 100mm lol I thought they were 70mm lol.

 

[leaded50]

@Zephyr1
EDF Unit-https://www.horizonhobby.com/produc...5c30xGCBpTiAhvfW1R3KnZl441umbeqRoCMy0QAvD_BwE
ESC-https://www.racedayquads.com/produc...8ZJ5lV92Or9z6-ruQWqkBzjRRjWz061hoCb8UQAvD_BwE
Servos-https://www.racedayquads.com/products/emax-es9051-4-3g-digital-mini-servo?variant=31485582508145
Battery (4s 2200)-https://hobbyking.com/en_us/turnigy...i-jC8plix4PE42f4zGxoCxZkQAvD_BwE&gclsrc=aw.ds
Battery(5s 3000)-https://hobbyking.com/en_us/turnigy...zuu6q1axrg7o9nhNWPxoCCqYQAvD_BwE&gclsrc=aw.ds

I am going to be building this over a while and might need some help to decipher what part goes where on the plane.
Please tell me if you dont think that the parts I have chosen will work or if I will need to change some things.

Thanks for any help or advice!!
Nick aka Ranger_107.

If using the 70mm EDF as mentioned (and not a BDF) parts list looks close too ok.. without with a jet, i wouldnt trust 4.3g servos on elevator & rudder, perhaps ok enough for minor use at ailerons. A jet would have more speed and pressure on control surfaces. Or pwerhaps use 1 such servo of each part of the V-tail elevator surface.

The listed ESC is ok, and with BEC : " ref: "80A ESC! Complete with a 5.5V 5A BEC. "

 

[Ranger_107]

If using the 70mm EDF as mentioned (and not a BDF) parts list looks close too ok.. without with a jet, i wouldnt trust 4.3g servos on elevator & rudder, perhaps ok enough for minor use at ailerons. A jet would have more speed and pressure on control surfaces. Or pwerhaps use 1 such servo of each part of the V-tail elevator surface.

The listed ESC is ok, and with BEC : " ref: "80A ESC! Complete with a 5.5V 5A BEC. "

Will the 100mm edf fit in the scaled up version? or do I just need to keep with the 70mm edf?

 

[leaded50]

Will the 100mm edf fit in the scaled up version? or do I just need to keep with the 70mm edf?

who knows? if your readjusted plans to 125% , then it should be easy measure what space you have.
After what ive calculated, and tried check from plans.. nope. an 80mm should go, but thats not accurate tested.

 

[synjin]

By accident, don’t ask me how, I did what you are proposing here. I agree with Zephyr1 that the elevator needs to be made larger. I enlarged mine 125% and it worked pretty well . Unfortunately, I got too close to a tree, and then more unfortunately I got up close and personal with ground. I’ve finally come back to it and I am almost done with the rebuild.

Mine flew on a 3600maH 3S battery. It was a little tricky to find the CG. This picture is from last winter before the fatal spring crash.

 

[synjin]

I’ve been clearing my hobby table this week. Here’s the rebuild. I modified the motor mount using an F-86 balsa plan cross-section I found on the net. I rounded out the fuselage like Zephyr1 has on his newer builds. It probably would have been easier to use his 70mm plans, but I had these wings which were in good shape and are a little larger than the 70mm’s wings. Think I’ll paint it before the remaiden. The EDF is right behind the wings to get the weight more forward. I think it will balance with a 3600maH 3S right under the canopy.

 

[synjin]

Maidened mine today. 15 degrees, little wind, AND the parking lot was plowed making for a good landing area. The previous version needed a 3S 3600maH battery to balance. This one needs only a 3S 2200maH battery.

With ailerons on the wings and elevons in the back it handles well. Rolls, turns, and one loop, though it doesn't have a lot of power running a 3S. I need a bigger 4S to see how that works. I had to run 2/3s throttle to cruise. I will say that it glides like nobody's business. I cut the power at about 30' and got it to the ground by the end of the parking lot, about 200-250'.

Guess after not crashing it I'll have to give it a paint job.

Ranger_107, did you build one?

 

[synjin]

4S is the way to go.

 

[Timmy]

I'm adding this to my build list!

 

[synjin]

So, after banging up my other planes I took the F-86 out today for a fly. Still great fun!