V-1 Rebuild 2020

probably best I keep my mouth shut then

I fear there is no LED because something is burned out, hence the odour. I may be wrong but some cheap rx are not proof against the ESC plug being put in the wrong way round.
It is marked but the markings are not in the plane of the end pins so it is open to 'interpretation'. The positioning of the markings is of course sensible for top or no pins. Both these configurations of this rx are available.

Soldering the pins onto the rx seems to have worked ok. Definitely not as neat as done properly with a solder bath but all the channels work and continue to do so even when trying to wiggle the whole pin block.
So work can resume completing the V-1 except LH aileron servo did not move. Its all built in and has been there untouched for nearly 7 years. Drat and double drat!
So with two small skin cut outs the servo and its long wire could be extracted leaving a string pull through behind.
The wire was cut off close to the servo and a plug soldered on but still no joy with a servo tester. A new servo added (last 3.7g!) to the existing wire and it worked. With the new servo glued in and the wire drawn back using the pull through it was tested again allowing the skin made good.

With the new rx installed and everything tested again the upper portion of the nose is glued on.

Just a battery hatch to make and the nose cone to glue on and it will be ready to hang back on the wall for 4 weeks.

That will conclude all my 'broken' planes. What next?

Might I suggest having a rummage through the spares dept, seeing what you've got, & start from there ?

The final picture of the 2020 rebuild, ready to go but hanging on the wall.

I do actually have one more 'crashed' plane. Its in the roof so 'out of sight out of mind'.
The VTO V-2 with wings (A4B).

It is now in a very sorry state as its EDF blew up and the blades (all of them!) did quite a bit of structural damage to the rear end as they left and some 600 mm of the nose was lost as it dived in.


Impressive but ridiculously fragile. Every time it flew I had the feeling it was on borrowed time.

Any idea what caused the fan to let go Simon? Always amazes me how much stored energy things have, when the rubber motor went on my swallow (right next to my head!) it sounded like a gun shot!

paul
Basically is was a 3s fan and I was running on 4s! :woohoo:
I judged the 1.5 m long motor wires would drop the voltage a bit and of course full power was only applied for a few of seconds before it was in danger of being OOS! It went up pretty fast as it had a thrust to weight of 2:1.
The one factor I had overlooked was the additional forces on the blades generated from instantly slamming the throttle full open. I am pretty sure this was the mode of failure as there was just a big bang with no vibration as the EDF blew at about 10ft off the ground. Inertia took it to 20 ft when it 'toppled' and dived in. It was all very realistic.
I was using an AEO 70 mm 3 s EDF simply because it was the lightest available, a vital attribute with the EDF in the tail. The 1800 mAh 40C 4s had to be right in the nose for balance.

Blimey! that must have been a shock letting go so close! would having the motor further up the body and having a augmentor tube work? providing it gets rebuilt of course.

The result of its first flight after the 2020 rebuild. :woohoo:

As explained in the Fying thread it was slightly tail heavy and the ESC kept cutting out and with is high thrust line resulted in a severe nose up pitch. With no power and slightly tail heavy made the pitch up severe. Nursed it for a while but eventually a full stall meant a nose plant.
Apart from the nose cone and the first 5 formers no other damage.
The reprinted formers on temporary 'keel' strips ready for 3 mm planking.

The battery will be positioned so it fits right into the nose cone to move the CofG forward a bit.

The 'half' nose complete.

It is actually the bottom half. It makes installing the Battery, ESC, elevator servo and Rx much easier before the top half skin is added.

I also discovered why the EDF kept cutting out . It draws 36A at full power and I am pretty sure it is a 30A ESC! :woohoo:
The strange bit it is the same ESC that has flown without trouble for about 3 years.
The upper ESC in the picture is the original 30A. It does have a substantial finned heatsink which might explain how it survived for so long.
The lower one is the 40A replacement with a more thermally efficient 'fingered' heatsink.

is there anyway the esc could be surface mounted?
All the brushless buggys I work on have fan cooled esc's and cant remember having to change one that had seen normal use,may be worth thinking about.

Paul
The original and the new were/will be mounted with their heat sink fins standing proud in the airstream.
This arrangement has certainly works on my other similarly powered EDFs.

To be honest I was amazed at the 36 A reading. In fact as I write this I am getting concerned as all the info I can find on 55 mm EDFs, although this particular one is no longer made, suggest even the current 8 blade version only draws 21A on a 3s! :woohoo:

I fear I may have made a classic mistake in assuming it was the ESC that was over loaded rather than the load itself may have changed!
I will have to investigate further.

Update
I have just run the identical fan in my HP 115 and it draws 24A max. So the answer its V-1's EDF that is at fault! It certainly runs ok but may be over time the fan has 'grown' at bit and the blades are touching. If they are it would certainly ramp up the amps with little loss in performance.

I think this does rather confirm there is something amiss with the fan.

I doesn't look like just gentle scoring either!


Anyway the nose half shell is glued on and the battery box built in.

So much easier when you have unrestricted access.

Just to add to the fun my expensive and rather small sheets of 2 mm Depron have arrived so work can restart on the 'fan forward' nacelle of the HE162.

Perhaps the duct has been squashed ever so slightly, somewhere in it's lifetime! :evil:

I agree Eric, much more likely the duct has deformed.