Edge 540 - Please feel free to comment

[TheFlyingBrit]

Okay, I finally got to evaluate the Edge following last weeks diabolical flight attempt.
I connected the power meter today using the original Turnigy plush 32 - 40 amp ESC, I also refitted the original 12x6 prop and used a 3s 2200mAh battery supply.
Interesting result, first point of interest the vibration was back - so obviously a prop imbalance problem (yipee my spinner is probably okay).
I spooled up the motor, initially the voltage was 11.7v. As I reached full throttle the current peaked at 25-26 Amps and the wattage reached 260-270 max, average was around 260 Watts.
There seemed plenty of thrust, but something wasn't right (besides the prop vibration).
I checked the motor spec (Emax GT2812/09 1060kv).
1) A 3s battery with 11x5 prop should pull around 25 amps with 1350g thrust.
2) A 3s battery with 12x6 prop should pull around 34 amps (hence my 40 amp ESC selction), the expected thrust should be 1450g of thrust.

So my setup is producing less power than the specification to start with, that is one concern.

Secondly I noticed that the motor seemed to be pointing downwards, which is odd as I seem to remmember there was no down thrust when I first built it.
I repaired the motor bay and power pod section a while back. This was following a belly land where the prop hit the ground first, damaging the motor mounting.
I am 99% certain I have flown it since then with no issues, although I am getting old and senile so who knows .
Being naturally analytical, I had to check the motor for movement and discovered there was some flex of 5mm up and down. I realsied at this point that the down thrust was probably more pronounced than I first thought.

Next Job, remove the cowl, sensibly as it needs to go back on eventually. I always thought it should have been removable, bad design flaw having it fixed.
I can then access the motor mounting properly and decide if I should level out the motor angle ? I would like some advice on this from other builders.

Before anyone ask's I didn't recalibrate the ESC and didn't get chance to try out the new Hobby wing 50amp either, as the bullet connectors where too small for connecting to the motor leads.
Thats a job for tomorrow I suspect and a re-run of the power test with the new 50amp ESC.

 

[TheFlyingBrit]

Okay, I finally got to evaluate the Edge following last weeks diabolical flight attempt.
I connected the power meter today using the original Turnigy plush 32 - 40 amp ESC, I also refitted the original 12x6 prop and used a 3s 2200mAh battery supply.
Interesting result, first point of interest the vibration was back - so obviously a prop imbalance problem (yipee my spinner is probably okay).
I spooled up the motor, initially the voltage was 11.7v. As I reached full throttle the current peaked at 25-26 Amps and the wattage reached 260-270 max, average was around 260 Watts.
There seemed plenty of thrust, but something wasn't right (besides the prop vibration).
I checked the motor spec (Emax GT2812/09 1060kv).
1) A 3s battery with 11x5 prop should pull around 25 amps with 1350g thrust.
2) A 3s battery with 12x6 prop should pull around 34 amps (hence my 40 amp ESC selction), the expected thrust should be 1450g of thrust.

So my setup is producing less power than the specification to start with, that is one concern.

Secondly I noticed that the motor seemed to be pointing downwards, which is odd as I seem to remmember there was no down thrust when I first built it.
I repaired the motor bay and power pod section a while back. This was following a belly land where the prop hit the ground first, damaging the motor mounting.
I am 99% certain I have flown it since then with no issues, although I am getting old and senile so who knows .
Being naturally analytical, I had to check the motor for movement and discovered there was some flex of 5mm up and down. I realsied at this point that the down thrust was probably more pronounced than I first thought.

Next Job, remove the cowl, sensibly as it needs to go back on eventually. I always thought it should have been removable, bad design flaw having it fixed.
I can then access the motor mounting properly and decide if I should level out the motor angle ? I would like some advice on this from other builders.

Before anyone ask's I didn't recalibrate the ESC and didn't get chance to try out the new Hobby wing 50amp either, as the bullet connectors where too small for connecting to the motor leads.
Thats a job for tomorrow I suspect and a re-run of the power test with the new 50amp ESC.

Well there will be no progress today on my project as I am looking after a very arractive, dark haired young lady who is very demanding




My sons dog - Shiva, the German Shephard (she is 12 months old now how time fly's)

 

[Matthewdupreez]

Well there will be no progress today on my project as I am looking after a very arractive, dark haired young lady who is very demanding




My sons dog - Shiva, the German Shephard (she is 12 months old now how time fly's)
View attachment 212484

 

[The Fopster]

My motor is straight - no down/side thrust as far as I can see.

Another idea - I built mine with the front cowl removable. It slides on and is secured simply with a bit of tape on either side. I seem to remember adding a simple bit of added structure that it aligns to, and it just slides straight on. Once you’ve got your cowl off might be worth trying a non-permanent reinstall. I’ve needed to take mine off several times due to ”issues” with the speed at which I hit the ground at the end of a flight... 🤣

 

[Tench745]

Okay, I finally got to evaluate the Edge following last weeks diabolical flight attempt.
I connected the power meter today using the original Turnigy plush 32 - 40 amp ESC, I also refitted the original 12x6 prop and used a 3s 2200mAh battery supply.
Interesting result, first point of interest the vibration was back - so obviously a prop imbalance problem (yipee my spinner is probably okay).
I spooled up the motor, initially the voltage was 11.7v. As I reached full throttle the current peaked at 25-26 Amps and the wattage reached 260-270 max, average was around 260 Watts.
There seemed plenty of thrust, but something wasn't right (besides the prop vibration).
I checked the motor spec (Emax GT2812/09 1060kv).
1) A 3s battery with 11x5 prop should pull around 25 amps with 1350g thrust.
2) A 3s battery with 12x6 prop should pull around 34 amps (hence my 40 amp ESC selction), the expected thrust should be 1450g of thrust.

So my setup is producing less power than the specification to start with, that is one concern.

Secondly I noticed that the motor seemed to be pointing downwards, which is odd as I seem to remmember there was no down thrust when I first built it.
I repaired the motor bay and power pod section a while back. This was following a belly land where the prop hit the ground first, damaging the motor mounting.
I am 99% certain I have flown it since then with no issues, although I am getting old and senile so who knows .
Being naturally analytical, I had to check the motor for movement and discovered there was some flex of 5mm up and down. I realsied at this point that the down thrust was probably more pronounced than I first thought.

Next Job, remove the cowl, sensibly as it needs to go back on eventually. I always thought it should have been removable, bad design flaw having it fixed.
I can then access the motor mounting properly and decide if I should level out the motor angle ? I would like some advice on this from other builders.

Before anyone ask's I didn't recalibrate the ESC and didn't get chance to try out the new Hobby wing 50amp either, as the bullet connectors where too small for connecting to the motor leads.
Thats a job for tomorrow I suspect and a re-run of the power test with the new 50amp ESC.

I would suggest trying this test again with a fully charged battery first; a charged 3S should be at 12.6V.
After that I'd recalibrate the ESCs and try it again to see what kind of change you get.

 

[TheFlyingBrit]

I would suggest trying this test again with a fully charged battery first; a charged 3S should be at 12.6V.
After that I'd recalibrate the ESCs and try it again to see what kind of change you get.

Well spotted and a good point made. Unfortunately, I didn't have a fully charged 3s battery at the time, as all my batteries are in storage at present.
The selected battery I used was in a storage state, it could have had some impact on the result.

 

[TheFlyingBrit]

My motor is straight - no down/side thrust as far as I can see.

Another idea - I built mine with the front cowl removable. It slides on and is secured simply with a bit of tape on either side. I seem to remember adding a simple bit of added structure that it aligns to, and it just slides straight on. Once you’ve got your cowl off might be worth trying a non-permanent reinstall. I’ve needed to take mine off several times due to ”issues” with the speed at which I hit the ground at the end of a flight... 🤣

I was fairly certain there was no down thrust, but thanks for confirming . I am definitely modifying the existing cowl to a removable version, as its just impractical when you need to do maintenance on the motor. There is no access space from the front, I'm not surprised I screwed up the power pod angle during my repair, after all I am not a gynecologist.

 

[TheFlyingBrit]

Okay I finally got around to some more power testing today, this time with a fully charged 3s battery.

First up was the Turnigy 40amp 32plush ESC - Peak power 290 watts, average 280 watts, amps 26.
Second was the Hobbywing 50amp ESC - Peak power 300 watts, average 284 - 290 watts, amps 27.

A marginal difference between them really, which is good because it tells me the Turnigy ESC is working okay, as its comparable with a freshly calibrated Hobbywing ESC.

Now the Motor and ESC have been vindicated, I was back to the down thrust being the problem. I know that I am getting old and suffering short term memory loss but I was certain I flew it after the power pod and mounting former repair although now I am doubting my own sanity and memory.

Next job was removing the cowl with surgical precision, as it is going back on eventually but as a removable version. The down thrust is visible with the naked eye (sorry admin I used the word naked). If you can see it, there is definitely too much down thrust, so next job modify the mounting to give a zero thrust angle.
Once that's done I can work on making the cowl removable and finish off the other minor repairs needed to get it airborne again.

I also need a new prop balancing rig in the new year, more expense .

 

[TheFlyingBrit]

Okay, I finally got to evaluate the Edge following last weeks diabolical flight attempt.
I connected the power meter today using the original Turnigy plush 32 - 40 amp ESC, I also refitted the original 12x6 prop and used a 3s 2200mAh battery supply.
Interesting result, first point of interest the vibration was back - so obviously a prop imbalance problem (yipee my spinner is probably okay).
I spooled up the motor, initially the voltage was 11.7v. As I reached full throttle the current peaked at 25-26 Amps and the wattage reached 260-270 max, average was around 260 Watts.
There seemed plenty of thrust, but something wasn't right (besides the prop vibration).
I checked the motor spec (Emax GT2812/09 1060kv).
1) A 3s battery with 11x5 prop should pull around 25 amps with 1350g thrust.
2) A 3s battery with 12x6 prop should pull around 34 amps (hence my 40 amp ESC selction), the expected thrust should be 1450g of thrust.

So my setup is producing less power than the specification to start with, that is one concern.

Secondly I noticed that the motor seemed to be pointing downwards, which is odd as I seem to remmember there was no down thrust when I first built it.
I repaired the motor bay and power pod section a while back. This was following a belly land where the prop hit the ground first, damaging the motor mounting.
I am 99% certain I have flown it since then with no issues, although I am getting old and senile so who knows .
Being naturally analytical, I had to check the motor for movement and discovered there was some flex of 5mm up and down. I realsied at this point that the down thrust was probably more pronounced than I first thought.

Next Job, remove the cowl, sensibly as it needs to go back on eventually. I always thought it should have been removable, bad design flaw having it fixed.
I can then access the motor mounting properly and decide if I should level out the motor angle ? I would like some advice on this from other builders.

Before anyone ask's I didn't recalibrate the ESC and didn't get chance to try out the new Hobby wing 50amp either, as the bullet connectors where too small for connecting to the motor leads.
Thats a job for tomorrow I suspect and a re-run of the power test with the new 50amp ESC.

It wasn't the ESC good news the turnigy 40amps okay

 

[mastermalpass]

Next Job, remove the cowl, sensibly as it needs to go back on eventually. I always thought it should have been removable, bad design flaw having it fixed.

Unless I'm building something small and simple, my planes are built to be disassembled, or they end up having hatches cut in them. Planes just so often need maintenance! Even the Bipe Pipe, though intended to be small and simple got a hatch cut in the side 'cause I did a bad job of soldering the ESC wires to the motor wires.

When I imagine building a plane with flaps, retracts and tip lights, I imagine building the wings with a cable channel inside and hatches to access everything. When deciding where to put servos, a voice in my head is always ready to ask; 'and how are you going to get to the servo, should you need to adjust anything?' I just hate having to break planes in order to fix them!

 

[TheFlyingBrit]

My good friend Bill taught me a great tip with servos. Wrap them in electricians tape before you hot glue them into position. That way if you need to remove them in the future, just simply cut the electricians tape which remains attached to the glue the servo is then easily be removed.

 

[mastermalpass]

That is a damn good tip!

 

[TheFlyingBrit]

He is full of useful ideas like that

 

[PsyBorg]

The entire nose of the 540 is its weakest point. I had the same issue when I first tried to fly mine. A very miner bump on the nose and that motor mounting system tends to point down. I will say though even though I tried to do as you and fly with down thrust it is still the longest flights I have had on a fixed wing so far. Here is the first attempts to get it in the air. What I didnt realize was I started out gimped with a down thrust angle just from doing the glide test to find neutral CG from a slightly crumbled motor mount that did not show obvious damage since the cowl was not affected.

This is what the motor mount looked like after the maiden. I was surprised I did as well keeping it airborne and level that third attempt in the video. I'm going to guess there was a good 15 to 20 degree down and another 10 - 15 to the right after that maiden attempt. But I took off easily enough with a straight albeit slower roll out than others like.

I rebuilt my motor mount by doubling the foam plate under the mount as well as adding a 3 layer triangle support underneath. I also did a box spar type thing behind the motor so it had double layer of foam all around the box. On hindsight I think I should have just replaced that lower flat section with a piece of balsa ply.

I have also decided to make the cowl at least partially removeable so I reconstructed the lower half and glued that back on. That was as far as I got on the repair.

 

[TheFlyingBrit]

The entire nose of the 540 is its weakest point. I had the same issue when I first tried to fly mine. A very miner bump on the nose and that motor mounting system tends to point down. I will say though even though I tried to do as you and fly with down thrust it is still the longest flights I have had on a fixed wing so far. Here is the first attempts to get it in the air. What I didnt realize was I started out gimped with a down thrust angle just from doing the glide test to find neutral CG from a slightly crumbled motor mount that did not show obvious damage since the cowl was not affected.

This is what the motor mount looked like after the maiden. I was surprised I did as well keeping it airborne and level that third attempt in the video. I'm going to guess there was a good 15 to 20 degree down and another 10 - 15 to the right after that maiden attempt. But I took off easily enough with a straight albeit slower roll out than others like.

View attachment 213010

I rebuilt my motor mount by doubling the foam plate under the mount as well as adding a 3 layer triangle support underneath. I also did a box spar type thing behind the motor so it had double layer of foam all around the box. On hindsight I think I should have just replaced that lower flat section with a piece of balsa ply.

View attachment 213009

I have also decided to make the cowl at least partially removeable so I reconstructed the lower half and glued that back on. That was as far as I got on the repair.

I went for the 1/16 plywood bracing on my re-build but the whole repair was carried out with the cowl in place. So I missed the motor angle problem until recently that is.