FOAMSLAYER
New member
any good ez pack designs on the forum recommendations?
Anybody else scratch building tonight?
- Thread starter K3V0
- Start date
Bo123
Elite member
Thanks, its very underpowered tho so I need to work on that.
shadeyB
Legendary member
Epic little flyer and sounds sweet too
congrats buddy
Foamforce
Well-known member
Nice. I was just out fooling around with mine yesterday. Did you do your paper on or off? Did you scale it to fit DTFB or adjust the slots?
luvmy40
Elite member
Paper on, mostly. I only scaled the slots and did have some fit issues. Mostly with the firewall mounting. Which, I'm thinking was the main reason I had a dismal maiden experience.
This was my first time flying a pusher. First time flying an Elevon plane. First time adjusting plans to fit DTFB. A lot of firsts and, as I said, a dismal failure.
Foamforce
Well-known member
Oof. Looks tail heavy? The COG points on this design are about a half inch long vs the dots that we’re used to. I took that to mean it was a range of COG with most acrobatic toward the back and most stable toward the front. I went right in the middle. Regarding the motor placement, my 1806 motor was apparently shorter than what the original design used, so I had to add two extra pieces of foam under the firewall to center the prop in the slot.
Did you try a glide test?
mastermalpass
Elite member
Ooh dear, sorry to hear that went so awry, I designed this thing specifically to avoid such mishaps. It is certainly eliciting a tail-heavy characteristic, despite your reports of it being nose-heavy. Then again, with mine, I cannot get it to be any less nose heavy than just about balancing on the leading corners of the notches, but even then, this plane is meant to be steady on the pitch and the CoG is indeed supposed to be gradient.
I'm surprised your motor came up too short, it's designed to use an Emax racing quad motor, can you supply a close up pic of your motor mount arrangement? I'm wondering if I can spot any issues there.
Mr NCT
Site Moderator
You will love the Spitfire. It's a joy to fly.
luvmy40
Elite member
I didn't take any detail pics before the maiden.
Basically, the rear of the upper and lower fuse did not line up with the rear edge of the motor mount vert. insert. The foam backing on the 3D printed mini firewall was glued to the X created by the wing and insert. No perimiter support. It looked(to the naked eye) like it was straight and square to the assembly, but I'm sure there was a good bit of flex there. The prop looked to be in the correct position, i.e., centered in the slot area.
I was running a 3S 1300mAh battery and had to push it back as far as it would go to not have it super nose heavy. Of course, I was just using my finger tips as a balance and may have been at the back of the slots rather than the middle or front.
I do plan on cutting another soon and trying again.
Foamforce
Well-known member
Here’s mine. I just added a couple pieces of foam under the motor mount. I used a FT mini firewall. The motor is a generic 1806-2200. Flies great!
Attachments
mastermalpass
Elite member
I didn't take any detail pics before the maiden.
Basically, the rear of the upper and lower fuse did not line up with the rear edge of the motor mount vert. insert. The foam backing on the 3D printed mini firewall was glued to the X created by the wing and insert. No perimiter support. It looked(to the naked eye) like it was straight and square to the assembly, but I'm sure there was a good bit of flex there. The prop looked to be in the correct position, i.e., centered in the slot area.
I was running a 3S 1300mAh battery and had to push it back as far as it would go to not have it super nose heavy. Of course, I was just using my finger tips as a balance and may have been at the back of the slots rather than the middle or front.
I do plan on cutting another soon and trying again.
I think I might adjust the CG notches forward a bit on the design. The first version was all over the place when tail heavy, but nose-heavy can be worked with. I did a version of the Delta which had a KF-2 Airfoil on the main wing, but not the canards. All that added lift aft of the CoG made it really 'nose heavy', so much so I too had to put a 3S battery as far back as I could. It then still needed a fair bit of trim but once that was figured out, it flew a really nice straight and level. The version was overstable and a little squirelly when trying to turn and so the KF edition was scrapped, but the point is, the safe side is, as usual, nose heavy.
By the way, a 1500mAh 3S is a bit on the heavy side. That's almost double the weight of the 800mAh 3S it was tested with and that was more than enough supply for it. Do you have a lighter battery you can use?
Foamforce
Well-known member
The 2s 650 is probably good. I fly mine with a 2s 450 and a 3s 550. The weight of a 2s 650 is right between those. The 2s 450 flies better, but the 3s 550 makes up for it with ridiculous speed.
A 3s 1300 weights over 4x more than a 2s 450. The all up weight of mine (including the battery) is 163g. The weight is the 3s 1300 alone is 122g. I think weight might be your biggest issue.
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