More Tools in Progress

Here are some of the raw parts that will turn into our Mylar Spooling tool, and the Leading Edge Bending tool.

The Mylar Spooler tool will allow us to spool off several hundred meters (about 10 kg worth) of the specialized 'tensilized' Mylar we plan to use from the 500 kg roll it is currently on.  The two large aluminum tubes in the front of the photo weigh 8 kg (18 lbs) -- they have to be strong to hold up the 500 kg (~1000 lbs) roll.

The Leading Edge Bender will let us form the tight leading edge on our Depron foam leading edges by heating the foam with a heating element that sits inside a 3/4" OD aluminum tube, and bending the Depron around that tube.

Back in the Game

This is the first post in 4+ months.

An unexpected family health emergency put a crimp on any significant work on DaSH since mid-December 2012.

Now we are back on track and working on the plane again, with hopes to finish the bulk of construction and assembly by late-Summer this year (2013).

The next two weeks will be focused on finishing the design of the airplane itself, including 3D CAD layout, as well as completion of a Design Guide detailing the construction techniques for all parts of the plane.  Then early May will be devoted to designing and building the custom tools that will let us build the parts of the plane, including tools for building the wing rib skins and leading edges, the anti-buckling 'biscuits' that go inside the carbon fiber tubes, and for handling the Mylar covering of the plane.  Once these tools are complete and tested, we'll begin the construction of the plane itself.

One of the tools is already underway, the Wing Rib Skin Clamp, which lets us put an appropriate jog in the thin .4mm plywood that is used to skin the wing ribs.  (In front of this jog, the 3mm thick Depron foam leading edge will fully cover the ribs, behind it, the covering is only Mylar).

Here are some photos of the tool Wes is building, currently in progress:

The piece shown is a 24 " long aluminum piece with the 3 mm deep jog with radiused edges running down the center.  This piece will get cut into two 12" pieces, which will mate together to form the clamp for the jog, and guiding pins and bolts at each end will hold the two halves of the clamp together, with an approximately 10" working area.

48 inch long X 10 inch wide strips of the .4mm thickness plywood will be heated, steamed and/or treated with an ammonia/water solution to make them flexible at the jog, then the jog will be formed with the clamp and the pieces allowed to dry.

The resulting pieces will be cut into 2" or 4" wide strips, as appropriate, and then glued to the top and bottom surface of the hot-wired foam rib pieces.  When dry, 6 mm thick ribs will be cut from the assembled rib pieces using a fine-toothed band saw (yielding 5+ pieces from a 2" wide foam rib, or 10+ pieces from a 4" wide piece)