A printed plane or not as the case may be!

I have to say that is quite impressive ! I do like the fact that you have used both modern & more traditional methods & materials in the construction. Building that light is an art form, one that I have yet to learn ! :lol:
Look forward to the Mk2 flight video.

Here we go again with the Mk 2 Print Tractor, hopefully making use of the info gained so far.
As expected the fuselage had to be destroyed to release everything along with the wing underside centre tissue!

Next job is to extend the servo wires (and shorten the ESC to rx wire) so motor, ESC and Tx can all be extracted out the front.
I am also considering retaining the wing with rubber bands.

The Mk2 structurally complete.

It looks virtually identical but the printed fuselage is completely new and not even glued together in the same way.
It now weighs 237 g. 2 g lighter than before.
The wing will be held on with rubber bands to allow a bit of 'give' when a wing tip touches on landing which it always does as the fuselage is so shallow and the dihedral so small.
As it as a printed structure it would be quite possible to give it a true gull wing to improve the tip clearance.
I wonder........

If it gets any lighter you could put a string on it & fly it as a kite !:woohoo: :evil:

Although the Mk2 flies well enough its flight characteristics are not 'nice'.
I suspect it is a mix of virtually no dihedral coupled with very limited fuselage side area. In addition the plank constant section wing seems to drop a wing (either!) dramatically at the stall.
So over the last few days I set about a redesign but using the same construction principles.

It now has a modest polyhedral and the wing section is thinner, 10% root to 6% tip, rather than the previous constant 12%. The point of maximum thickness (the spar) has been brought forward from 33% to 28% chord and the spar itself has more taper reducing from 12 mm deep at the root to just 5.3 mm at the tip with the rib depth reduced appropriately.
I does still pass my 'wing tip test' for a 250 g all up weight although it does bend a bit.

I have no idea if these changes will make any difference but it is following the wing design of the sub 250 g Depron Light Tractor that I flew today and that flies very well indeed.

If that doesn't work, could you not modify the plank wing to a "cuffed" wing ? Just a thought.

Seem to be a lot of other non RC jobs that are slowing this down but the ailerons are covered and the servos mounted.

This view shows its mild polyhedral.

It lighter than the first sub 250 g wing as well!

The new lighter wing completed.

It now weighs 227 g down from 240 g.
The whole tail assembly now looks almost 'clumsy' in comparison. Hopefully a few more grams can be saved.

Just before I took the picture I was testing to make sure everything worked but no joy. Not even the LED in the rx light up! ESC failure?
After much checking I even went to the trouble of connecting up a different motor and ESC and even checked that worked using a servo tester but still no joy when connected to the rx . Had the rx lost bind? Then I noticed the 'search' button on the rx.
Since when did 2.4 have a search function?
Then it dawned on me. I was trying to use a 35 meg rx with a 2.4 tx. Doh!
What a plonker!

Despite some flying and the best attempts of my daughter to get me involved in remodelling and re plumbing her kitchen I have managed to continue with the improvements to the Print Tractor.
The original version at 239 g.

With the light weight wing added last week.

To the new light weight V tail this week but not yet flown.

The prop has been changed from a 6 x 3 to a 6 x 4.
It now weighs 219 g'
Not that it really proves anything, other than I must be completely daft, as each gram saved has taken about an hour of 'trial and error' printing to achieve! :woohoo:

You have to be daft to indulge in this crazy hobby, anyway! :woohoo:

Not daft, it's a magnificent obsession!

The Print Tractor with the rebuilt V tail that has the elevator servo in the left hand side so it operates in the same sense as all my other 35 Meg planes.

As far as looks go the difference is minuscule but the construction and finish of the V tail is much improved.
It still weighs exactly 219 g ready to go.

If the weather forecast improves I hope to go to a 'fly in' this weekend but there are gales forecast (40 mph +) in the area for Friday. :woohoo:

As I intended to take th elatest version of the Print Tractor to the Open Day, although the weather forecast is not good and certainly not for a sub 250 g lightweight I decided to 'pretty it up' a bit.

This also rather demonstrates the lunacy of this development.
In its first completed state it looked like this.

It may look pretty similar but in fact the only common part between the two air frames is the tail boom! :woohoo:

After the very unsuccessful maiden yesterday it is all back together and the elevator link rod has been made a bit longer to account for the incorrectly positioned servo arm.
It doesn't look any different but then within the accuracy of the 3D printer it isn't!

In fact all the fuselage ahead of the wing band hooks is new.

Rotten weather forecast for quite a few days.