Post by Burkeomatic on Feb 27, 2023 5:07:08 GMT
Ok, instead of crapping up droneflyer's thread moreso than I already have, I have determined the modifications needed to make the EDF Flerken "sustainable" and that will be discussed here.
Many people are familiar with Ben Harber's not so successful attempt at EDFing a Flerken. I noticed his problem pretty quickly having experience scratch building and designing pushers and jets, his EDFs were above the wings, which would cause a pitch down moment. Anyone who has flown, built, and especially designed a pod mounted pusher can tell you that the center of thrust needs to point down at the center of gravity, and if it doesn't, you probably aren't getting off the ground. I am sure his plane would have flown fine once he got it up, but that was going to be a tough order.
So I had a mostly built flerken, and at the last minute I decided to EDF it. I had not started the design like that from the get go, and that will ultimately play a part on this plane's eventual failure.
My only choices were a 64mm 3S or a 6S 80mm. The 80 was probably too big and I didn't quite know how I was going to fit a 6s in it, so I went with the 64mm.
I built it, and I was amazed. I put 2 packs through it and the plane flew great. I thought I had officially conquered the EDF Flerken beast.
Having already had successful flights with the EDF Flerken, I wanted to upgrade it. I was using a little 3S 64mm Freewing EDF, and while it flew, it was wimpy on power.
I ordered up a new 64mm 4s EDF from value hobby. Now this was a little heavier and a little longer, so I cut about 1/2 of an inch out of the existing area... when I did that, it set me up for a whole host of failures.
Essentially what happened was I cut out all of the rear support, and the EDF, while it held in (mostly, until it didn't) allowed the wings to flex around. I noticed they felt a little mushy from the get go, but this plane never felt that solid.
So this will include a redesign of the rear section and wing reinforcement. You could probably do this if you ordered FT's quick build kit, but the little support pieces we need to leave in are pre cut out. Additionally, I guess I could make a plan section to where the EDF is cut out in the right piece and it includes all of the modified parts.
Additionally, I will be adding some wing reinforcement. A single paint stick would have stopped all of this.
Here is a video where I discuss my findings, review what I am going to do (sorry, I realized quality was poor after I trashed the plane) and I will walk you through building a new one.
Many people are familiar with Ben Harber's not so successful attempt at EDFing a Flerken. I noticed his problem pretty quickly having experience scratch building and designing pushers and jets, his EDFs were above the wings, which would cause a pitch down moment. Anyone who has flown, built, and especially designed a pod mounted pusher can tell you that the center of thrust needs to point down at the center of gravity, and if it doesn't, you probably aren't getting off the ground. I am sure his plane would have flown fine once he got it up, but that was going to be a tough order.
So I had a mostly built flerken, and at the last minute I decided to EDF it. I had not started the design like that from the get go, and that will ultimately play a part on this plane's eventual failure.
My only choices were a 64mm 3S or a 6S 80mm. The 80 was probably too big and I didn't quite know how I was going to fit a 6s in it, so I went with the 64mm.
I built it, and I was amazed. I put 2 packs through it and the plane flew great. I thought I had officially conquered the EDF Flerken beast.
Having already had successful flights with the EDF Flerken, I wanted to upgrade it. I was using a little 3S 64mm Freewing EDF, and while it flew, it was wimpy on power.
I ordered up a new 64mm 4s EDF from value hobby. Now this was a little heavier and a little longer, so I cut about 1/2 of an inch out of the existing area... when I did that, it set me up for a whole host of failures.
Essentially what happened was I cut out all of the rear support, and the EDF, while it held in (mostly, until it didn't) allowed the wings to flex around. I noticed they felt a little mushy from the get go, but this plane never felt that solid.
So this will include a redesign of the rear section and wing reinforcement. You could probably do this if you ordered FT's quick build kit, but the little support pieces we need to leave in are pre cut out. Additionally, I guess I could make a plan section to where the EDF is cut out in the right piece and it includes all of the modified parts.
Additionally, I will be adding some wing reinforcement. A single paint stick would have stopped all of this.
Here is a video where I discuss my findings, review what I am going to do (sorry, I realized quality was poor after I trashed the plane) and I will walk you through building a new one.
