|Apr 06, 2007, 03:25 PM|
575 Limit and 700 FlyingWing
Thought I would share with you my latest 2 designs.
The first is based on an older, standard tail version, of the tiny Germania Limit slope soarer. It was enlarged to a 575mm span from an origonal 455mm. It is powered by another cheap chinese motor which is designed to turn a 5x3 prop at 16-18000 revs on 11.1v
Goes well, it is fast and very agile
AUW 81/2 oz with an 800mA 11.1v lipo.
The motor draws about 6A at max power, but it flies well on 1/2 power.
The construction uses a depron skinned wing with an internal spar.
No ribs are used. The rear 1/2" of the wing skins are glued together with POR adhesive, the two skins are glued to the spar which is at the 1/3rd chord position. The depron skins at the front of the wing are pulled together and taped. with care you get a symetrical wing which is more than strong enough
The box Fuz is built of 1/16" balsa or 3mm depron. just like you would build any other fuz.
Tail and tailplane are from 3mm deprom
|Apr 06, 2007, 03:35 PM|
Heres a pic of the motor used.... another good little one at 22gm....
using a 7x3.5 prop you can get 10oz plus thrust. But its best for higher reving with a 5x3 and best used on the faster little models
|Apr 06, 2007, 04:00 PM|
My second model is a 700mm span flying wing. It has been scaled down from a Zagi plan and a fuz added below the wing to make the motor and radio easier to fit
The wing construction is the same as the 575mm limit
The fuz was made with 1/16" balsa but depron would be fine, It is a basic box fuz with a laminated depron nose shape added
I have a set of pictures to show the construction method
NOTE ...the pictures show the first build for the fuz, its position in the build was not good and it was later moved backwards to enable the required COG to be acheived with ease..
In the first build I was working using a scaled down zagi drawing and the indicated position turned out to be too far forward
I then rebuilt the fuz extending out the back and moving the motor 35mm back from the origonal position. The nose was shortened by about 30mm.
By moving the fuz backwards, the cut out for the prop is now not needed.
The ailerons can be lengthened so they go right next to the fuz
I couldnt bother doing this as my wing had already been built
|Apr 06, 2007, 04:17 PM|
Specs.... motor - same as the limit, a 2500K/v 22gm with a 5x3 prop
battery 11.1v 1200mA ...
2x 5gm servos towerpro used
hitec rec hfs 05ms
esc cheapo towerpro 12A
IMPORTANT ..... when launching the wing throw the thing, then power up the motor,,or your fingers will get the chop....OUCH I wont show you the pictures of that...
|Apr 06, 2007, 04:23 PM|
Joined Jul 2006
nice i was just looking for a plane for my c20 and i believe this is it! any more construcion tips?how do you affix the wing to fuse?just went through your drawing/instructions and i think i can pull it off. do you have some more build pics or at least some more angles of the Germania. also not good with mm,what does 575mm translate into inches? Really been wanting to do a mini pylon for a while, ive also seen some of your other designs a havent yet tackled one ,but the mini germania definitely caght my eye.(and imagination)
|Apr 06, 2007, 04:36 PM|
Hi danno the wing on my limit is removable and has a peg at the front for location and a overhanging top decking from the front of the fuz holding the front of the wing down
and there is a catch at the back which is held on with one nylon wing bolt this rotates to hold the rear of the wing.. but a permanent fixing would be ok.
I will be posting a lot of construction pics taken during the 700 wing build.
the method is much the same for the limit
The fuz is glued to the wing with uhu por and further held with packing tape.
All the decor is 2" wide colored sticky tape
the wingspan for the limit was suposed to be 600mm 24" but I must have cut it short when building..still it goes well, and with the front engine there are no launching problems.
will post more tomorrow getting late here....dave
|Apr 07, 2007, 12:30 PM|
They say a picture is worth athousand words...... I hope so, ... here are some construction photos of the 750 wings build.
If anyone wants some different angle shots or close ups of anything please post here and I will try to oblige
there are no build pics for the limit, but the fuz is built like any box fuz with some triangle in the corners and rounded off,
build the wing first then construct the fuz onto that.
I fitted two servos into the wing, just behind the spar side by side.. one for ailerons one for elevator once they were linked I put a false floor just above them for the battery to be fastened to with velcro.
With the limit its the wing shape that make it look good, the fuz can be made fatter or deeper as you like to accommedate the radio gear and you wont notice the difference when alls done
My one was made initialy as a sloper, then converted for elec power, so the radio space was a tight fit, but it went in after a fiddle about
If I were building again, possibly I would make the whole thing a bit bigger say 650mm or 700mm span, the proportionally larger fuz would then take the radio easier
|Apr 07, 2007, 12:36 PM|
1 ...wing skins and spar cut
2 ...spar glued to top panel, glue applied to rear 1/2" of both panels and glue along bottom panel where the spar will go and along the top of the spar
If you are making a tapered wing I recommend the top side of the spar is flat and the spar is tapered along its lower edges, glue the flat of the spar to the top wing first, on a nice flat surface,
Fit the lower skin, still using the flat surface, to make the whole wing flatest along the top surface with the "V" along the lower surface
My spars go from about 10mm at the centre to 5mm at the ends
uhu por for all joints here
|Apr 07, 2007, 12:56 PM|
Using 2" clear packing tape, 1" each for each surface the leading edges are pulled together accurately and fixed
Using 2" coloured packing tape some decor is applied
|Apr 07, 2007, 01:04 PM|
This is where the pics will vary from the recomended build.
I cut out a recess for the prop and fitted the ailerons.
I recommend that you forget the prop cut out and bring the ailerons further in, so as to be adjacent to the fuz.. This is because the fuz was moved rearward to get a good COG position and the prop now is well behind the wing and clears all the bits
|Apr 07, 2007, 01:14 PM|
The aileron servos were fitted in the top surface of the wing, just behind the spars
Recommended ...you can bring them in a bit more towards the fuz now that the ailerons are also closer
A false floor is now fitted to the lower surface of the wing, width of your battery plus a bit..the servo leads are pulled through a hole in the floor.
This floor is stuck to the wing surface at the thickest position and has some laminations of depron at the back to make it roughly line up with the centre line of the wing section
dont forget.. your floor will go 35mm further back, as measured from the centre of the trailing edge on the wing
my motor mount was fitted at this time
|Apr 07, 2007, 01:23 PM|
The fuz is built width and height as you need, but keep to the minimum size for your batteries rather than go too big
The rear of the fuz slopes up a bit to give a bit of shape and the corners here were rounded off as well
again dont forget...these pics show the fuz ends at the prop cut out...
yours should extend for 35mm behind the trailing edge, measured from the centre, with NO prop cut out