Because this Blog is updated regularly it is a good idea to visit at least once a week so as not to miss anything. If however you are not a regular visitor, please use the archive links, at the bottom of the side bar on the right, to view postings that have moved off the main page. Or type a key word in the search block in the black bar at the top left and click on "SEARCH BLOG" and it will take you to the posting within our Blog. (For instance, type "Jart" and all the post that mention Jart will open) The Label at the bottom of a post can also be used. Click to get all posts with the same label together!
This BLOG is best viewed at a screen resolution of 1024x768. Click here to get instructions on how to adjust your monitor to these settings.



Wednesday, August 01, 2007

SCALE DG 505

DG 505 ORION GLIDER

There has been a lot of interest in this new project and I was surprised at the response to the 2 x photos posted. Once again it becomes apparent that many modellers are interested in building techniques , so there will be a series of posts demonstrating the methods used.



PROJECT OVERVIEW


The choice of this subject was made based on the DG 1000 which is a state of the art 2 seater designed to compete with gliders such as the DUO DISCUS , after gathering lots of articles on the internet I decided to change to the DG505 as it used a wing planform that better suited my ideas on building a 8mtr plus wing. The intended outcome is a one off aircraft in the
15-20 kg weight class and wings in the region of 8mtrs span (4 pieces) with a fairly light wing loading. As before the goal is not to achieve scale perfection but rather an acceptable stand off scale appearance and good flight characteristics.


GETTING STARTED

If possible a good set of plan views is a must , I chatted to Paul from ETB about his FOX also scratch built and if you can get a set of plans enlarged to the size you want to build this is first prize , this is how Paul set about his project. The alternative is to scale up the drawing you have and mark up the sizes on the project using a calculator and tape measure.


These plan views will be a constant reference.
Some time ago I started collecting materials ,such as polystyrene foam from packaging and the for free part really helped, being resourcefull can lower building costs(to give you an idea a large scale , fully moulded kit of this size advertised in the USA would cost excluding shipping R45000.00 , although this glider is not in the same league , It is a goal to build this craft complete with airborn radio gear RX ,servos and battery pack for under R10000-00)








The foam is shaped out roughly with a hot wire and then moved to the sanding, take care the sander eats the foam at an alarming rate .The denser foam sands the best , after getting the basic shape right the foam is covered with packaging tape and waxed , this will aid removal
later. You will just see a centre line marked on the foam , this aids with sanding the sides the same.


The fuselage will be a one off , so the foam will be removed and discarded , due to its size it is not going to be melted out with thinners , but scooped/broken up and removed via the cockpit aperture.








The boom part of this fuselage is not made with foam, trying something a little new, a rigid cardboard tube was bonded into the foam , and a light cardboard rolled into a tube over the inner tube which is for surport and held in place with bits of tape.





A bit of care is now required as the tube is very flexable, it is also covered in tape and waxed,


the first layers of glass cloth and resin will "lock in the shape".

Only one layer of 163gr cloth is applied and it will have ridges in it as it drapes over the uneven packaging tape, I will show you how we handle these in the next part.

No comments: