Zeus
#1
Thread Starter
Zeus
There is still plenty of interest in IC pattern models. I looked at converting my Amadeus design but it is not really compatible. So a new design was needed to be powered by YS 200 or 50cc class two stroke. I'm calling it Zeus, Henry Piorun used the name but that was a long time ago so I am OK with it. The basic fuselage profile was designed in Autocad and is an Amadeus enlarged 15% in the height axis and then massaged into a final form. The fuselage area is a mighty 1100 sq. inches, bigger than the wing.
#2
Thread Starter
To give you an idea of the motor fit here are a couple of early versions with the YS and DA 50. As you can see there is also plenty of room for a couple of Tcans.
#3
Thread Starter
As usual this will be a molded fuselage. To produce the plug my method has been to transfer the profile onto a sheet of MDF. Glue expanded polystyrene to both sides and hot wire the top view then eyeball the rest. For this one I want to cut extruded foam slices on my CNC foam cutter and mount them on a length of rectangular section ali tube. This would require minimal sanding. I also get to look at the 3D version of the design as it needs to be modeled in a 3D CAD program first. I have recently moved over to Fusion 360 and spent some time getting to know it. This project was a good one to advance my CAD skills. It took a few attempts to work out a strategy in Fusion using the profile view from Autocad. I ended up doing it with 6 lofts, 2 rear fuselage, front fuselage, canopy, chin cowl and fin. I only lofted the right side of the fuselage then mirrored it for the left side. At the end of it my laptop was starting to struggle and it is no slug (8 core i7 16gb ram video card). Once I had the model I was able to massage the look and insert the motors to check for fit. The YS can move a lot rotationaly so was able to allow for that. The cowl may need a little blister to clear the exhaust during large excursions (backfires). Once I had it modeled I was able to work out where to cut the chin cowl and canopy hatches.
Last edited by RodneyFord; 02-13-2018 at 01:00 PM.
#4
Thread Starter
For most of the fuselage I am slicing it up into 95mm sections (100mm foam sheet less a surface skim). Fusion will output a drawing of each end of the slice for the foam cutter. Of course it is not as simple as that as the drawings need processing into the right format for the CNC foam cutter. This has been a learning curve too, but with the help of a few people in Germany and France I have it sorted. For each section 2 files are needed, one for each end. Fusion outputs these drawings which are a series of curves and straight lines. I open each one in Autocad and break the curves down into a series of short straight lines (this is automated). These get rejoined into a single multiline which is the path for the hot wire to follow. This drawing then gets converted (Profscan) into a data file that the CNC machine understands. However as each foam slice has a different drawing for each end they need further processing to make each end have the same number of line segments. This is a clever custom program called Echantillonnage it is in French so there was a fair bit of Google translate going on to learn it. The 2 files are then imported into the foam cutting program (GMFC) aligned and sized correctly then cutting can commence.
Here is a test piece but will end up as a 4 degree wedge at the tail post.
Here is a test piece but will end up as a 4 degree wedge at the tail post.
Last edited by RodneyFord; 02-13-2018 at 01:45 PM.
#5
My Feedback: (121)
Hi Rodney,
I will be watching with great interest! Technology sure facilitates complexity.
As for the name, Geez, how about Ares, the god of war? The Zeus was actually originally designed by a guy named John Nosler who then sold it to Henry. It is a fitting name... for what, I am sure, will be a superlative model!
I will be watching with great interest! Technology sure facilitates complexity.
As for the name, Geez, how about Ares, the god of war? The Zeus was actually originally designed by a guy named John Nosler who then sold it to Henry. It is a fitting name... for what, I am sure, will be a superlative model!
#7
Thread Starter
A battery weighs 1200gm a motor 600 Esc 100+ so that's at least 1900gm. My DA50 and ignition weigh 1560gm and know I can make a reasonably light custom header and can. For the airframe I can push the boundaries harder than commercial models so I am reasonably confident of making weight and have also designed in the lighter YS option. I want the weight to be as close to 5kg as possible and will size the wing/loading to suit. With the weight concentrated in the front I can move the wing forward for the longest possible tail moment.
#11
Thread Starter
More foam cutting. I will get this glued together now and can give it a sand. Doesn't need much. Just the cowl intake to shape by hand. Fin and canopy next.
#12
Thread Starter
Had a great weekend at IMAC comp flying my 42% Slick 360. Back into it, and cut out the canopy parts and glued them together with a bit of weight to hold it flat.
#14
Thread Starter
Spent some time fine tuning the fin. I use Profili pro for airfoils. I have SD8020 9.5% thick with the trailing edge thickened to 10mm at the root and SD 8020 12.5% thick trailing edge 10mm at the tip. Plenty of ribs to support the 3.2mm balsa sheeting.
#16
Thread Starter
Next up is lining the hatches. Put in some hard points so I can screw the hatches in place. I'm going to form the surface of the hatch with ACP (aluminium composite panel). Made a guide to cut out the Chin cowl.
#20
Thread Starter
Thanks Ricardo. Would love to visit in Uruguay. Buenos Aries is a good way to come back from Europe to New Zealand, maybe next time.
Canopy lining and forming the radius to avoid stress risers. All this becomes time consuming. I want to be surfacing next week and I am hopeful that it will be quick due to the already good surface.
Canopy lining and forming the radius to avoid stress risers. All this becomes time consuming. I want to be surfacing next week and I am hopeful that it will be quick due to the already good surface.
#24
Thread Starter
I'm forming the base of the canopy hatch. To allow for some clearance I have heat formed some 1mm styrene and double sided taped it to the fuselage hatch cut out. I have some 4mm threaded rod to hold it in position while the epoxy cures. I use a layer of 200gm glass and a mixture of epoxy and microfibres to form the surface. I'm relying on the release agent to get it off.
Last edited by RodneyFord; 03-07-2018 at 05:45 PM.
#25
Thread Starter
Got the glass and goop on. This has pushed up the front of the canopy hatch a little so it will need reshaping, all my good work undone. However I will treat it as a good thing as I can get more definition between canopy and fuselage.