Well,

I am starting off by stating the intent to build an Edge 540. In fact I am starting 2 threads side by side for two different types of constructions. I am not sure which one will take priority as both the models fascinate me

Now, listing some specs of the Edge that I am planning


1) Wing Span = 60 inch, wing root cord = 19 inch, wing tip chord = 9 inch, it will made as 2 part wing

2) Length = 52 - 54 inch(approx)

3) target weight approx 1200-1500gm

4) power approx 400 w motor on a approx 11 inch prop and 3 cell lipo approx 3000mah and 40 amp esc

5) 3.5mm landing struts with 5-6cm dia wheel

6) Construction material would be 5mm biofoam reinforced with CF rods, glass fiber rods, hard wood. covered with cloth and cured with either WBPU or epoxy, canopy would be made from 2lt coke bottle, hatch would be stuck using magnets

7) servos 17gm x 4

downloaded an image from the web attaching as a reference

Given the little time I get and the time I take to complete a model, its going to be a while before we start seeing some images

Pankaj

Pankaj

Do you have the plans for this / could you please share them?

VC, search/google for a model "Polybatic Edge 540". It is a smaller model and the construction would be different than what I plan, but you can use it. I usually take the "borrow" the physical dimension and adapt as I build

Nice .... Nice .... Nice..... good going Pankaj..... best of luck for the new venture....

thanks Divay, well as I said, starting two threads, the link to the other one is here http://www.rcindia.org/electric-planes/building-a-twin-pusher-su-37-super-flanker/msg70437/#msg70437

all the best pankaj...!

Thanks, RC Vish

Some progress after all. Decided to cut foam for wings. Got hold of thermocol 1.5 inch and cut four pcs for the wings. Its huge.... supposed to be 17 inch at the root and 9 inch at the time and about 28 inch for half the wing that will make the wings as 56 and the fuse width would be around 4-5 inch. So the total span would be 60inch

The problem is that this would be my first attempt at hotwire cutting for wing foils. Lets see how this goes.

This will be a good one, all the best Pankaj
That's a beautiful piece of foam BTW

good going ! all the best Pankaj 

 

That is some medium density thermocol (not biofoam). Cost me Rs 85-90 for a sheet of 1m by 1m. I bought 2 of these for 4 panels for the wings

Very interesting, keep posting updates...

Well, installed a trial version of a aerofoil designer, printed out the two ends of the wing aerofoil, pasted it on a biofoam sheet and cut a profile. Used it to transfer the shape on a strip of wood and with some bit of chisel and sand paper, achieved the following shapes.

First building the tail fins. For a foamie this size, decided to sandwich two pcs of 3mm biofoam together with a fibre glass rod in the middle and apply a 10mm x 6mm balsa strip all around for strength.

The balsa strip were procured from VKSingh (rcelectro) who laser cut the sheets for me

Enclosing for rudder and elevator

almost finished tail surfaces look like this. the 12" scale to give an idea of the size. The vertical fin is yet to be finalized. Think I will finish it last.

Pankaj... you Rock !!!

Nice too see you back with such a great build Pankaj sir!

Divay/Ujjwaana,

Thanks for the encouragement. Lets hope I can do justice to the build

Folks,
Decided to put up some build pictures.

For starters, this is somewhat semi finished pictures - not fitted the ailerons or the canopy, but should give you guys an indication on what this is going to look like

The problem that I have is that of storage. Given the dimension of the plane, its more than 44inch in length and more than 60 inch wingspan. So when I started building, the main concern was - "where the hell am I going to store this thing?" Then I decided to build the fuse in 2 parts and the wings in 2 parts.

When I started thinking about this, the next concern was that of strengthening the parts so that the bird does not break in flight (at least thats the thought)....

This meant additional weight....So how did I achieve this?

The fuse has a 1.5inch thermocol running length wise.

looking good

Fuse construction.....

Fuse construction

How I thought/implemented 2 part fuse..

The frame is built around the 1.5inch thick high density thermocol. So on the block, pasted some 3mm MDF pcs carefully laser cut (including the holes) by VK of rcelectro.

notice the parts and how it ends up. These decision on how to implement have been the most difficult part of the scratch build.

This was my first attempt to hotwire a wing.... turned out to be quite a disaster. The wing is tapered and then given the length, the two edges of the wing (base and tip) need to be cut in different speeds. Tried my best, but was not good enough.

here take a look. Lot of grooves and uneven surfaces...

Now the question was, how to join the wings?

The main spar is a 5mm CF rod. Along the 10-11mm mark from the LE. This is probably the CG location as well. So thought about cementing a sheet of 3mm MDF and joining them using a wooden strip like this...

So after joining the top and bottom end of aerofoil, the wing section looks like this.

Then the TE has been strengthened using 1.5mm balsa strip and the entire wing is covered with cloth and diluted fevicol. I used fevicol as I am having difficulty in locating WBPU.

The 2nd picture shows the wing dry fitted on the front portion of the fuse.

The 5 part plane.....

2nd pic is of the top dec. This is made from 0.5 inch depron (1 inch peeled into two along the joint)

Lots of finishing lets .... the nose needs to be finished. Ailerons need to be joined.. will keep posting as I go along.

as of now, the weight is coming to 1kg. So installing all electronics will take the AUW close to 2kg mark - a good 4-500 above the initial target.....

Awesome craftsmanship!! You detachable parts plane has inspired me to start thinking about a 3 meter "portable" flying wing; some very nice tips and tricks in this thread
From a picture in the first page, it looks like you have already finished covering the wing, can you please share what material you have used.

@sls.
The picture in first post is what i am aiming for. Not my model

I'm talking about this picture.

That is still not finished. Just sanded the wings with 220 grit paper. The deep cracks were first covered with a 2inch celotape and the wings then covered with cotton cloth "dhoti material" with diluted fevicol. Sanded again after drying.
Am not getting wbpu so trying various materials.

pankaj
you will need anti rotation pin, else the rigging will get compromised over a period

Hi Pankaj

I was on a lookout for Ecofresh Aqua Satin this weekend. I have found a dealer who has this in stock but he says it is defective (as he has recieved complaints of sedimentation from previously sold cans). In the mean time I have purchased a water based wood varnish ( white liquid) from him. Will let you know the result. Will use a mix of Epoxy+Hardner and Varnish on a fiberglass cloth on a test foam piece.

Here is the contact of the dealer :

The Paint people
342, Raviwar peth,
Bohri Ali, Pune
Ph : 24471532,24476626,24466062
email : support@aahakim.com
Website : A.A. Hakim

Well,
Update. Finally finished the build with basic finishing with primer and white acrylic paint.
As the width of the fuse is more than 6inch at the nose, attaching a 11 inch prop did not seem a good idea So the prop increased, this also meant that the current consumption increased and in turn meant bigger ESC and Battery.

So now, with 60am ESC and 4S 4000 mAH battery, the target weight is is 2350gm..... Way above the original target of 1500gms.

Anyway.. conducted field trials last Sunday.

Static test - the bird was way too much tail heavy so needed weight upfront. Divay managed to insert a 2200mah battery to somewhat correct the weight. We tried with 11x7 prop. Even though I had butterflies in my stomach, putting up a brave stoic face, asked Divay to maiden her. It did manage to get up in the air at full throttle and landed heavily after a short flight. On landing the wheels collapsed thereby the prop hit the ground and the motor mount came out. Nothing major and a big thank you to Divay.

But the 15 seconds flight was enough to convince all that 1) need more power - currently around 400W 2) need to strengthen the UC and motor mount.

Power I can add, but the question is how to secure a mount on a foamie when the motor is above 600-700W?

Pankaj

Update
Since the first test flight was under powered, went in for a another power source NTM 42-58 http://www.hobbyking.com/hobbyking/store/uh_viewItem.asp?idProduct=19610

This is a monstor of a motor and at 6S with a 14x8 prop is delivering 1300W of power. Imagine this on a foamie....

However, the weight has gone up further and close to 2.8Kgs because of the extra motor and battery weight.

There is substantial flex in the wings, that need strengthening, but for now, this is how it looks.

Picture clicked by Manish yesterday

 

Ideas welcome on how to remove wing flex without rebuilding entire wing afresh

Hello Pankaj,

Extremely nice build and really inspiring..Would be great to see some more pics, a video maybe..

Apart from all the things that are happening on our forum lately..this is so far the best thread..

peace..

Sir, I don't want to use an icon to say this...hatsoff to that build, and the paint job is supersome

Atul/Girish,
Thanks for the appreciation.....
I still am not capable to fly this, Divay has been doing the testing.... We did take the video last Sunday, lets see if I can post it.

regards
Pankaj

Fantastic build and color job.
What have u coated wings with ? If nothing then flex would be there ....
Try coating with fevicol and brown paper ( trust me it will make the wing strong). Put beeding sticks 5x30mm you get from any carpenters store. Put that along fuse also both sides. That should be enough I suppose.
Saurabh

Nope. That would still be weak!!!
Remember this is a 3kg foamie. Each half of the wing has a 5mm CF tube. The wibg is coveted with cloth and fevicol...
This bird needs more rigidity

yup i read your thread later..... in that case 5mm spar was a bad choice .. it should have been 15-20mm can you still do that .... or add another spar!!!

Sir go for minimum 12mm spar in this plane. You have seen how i make my duel 6mm spar flex in the air.