Subject: Twin project
From: Rotary Engine
Date: 4/13/2010, 1:56 AM
To: AAA Put this in the To box



 Paul and Jean, Scaling the 3Dm surface model is a single
 command operation
 if you are scaling to the same scale.I looked up a few Piaggio
 designs and
 found the listed airfoil as a NACA 23012 at the root and a 4412 at
 the tip
 on both the main wing and the stabilizer and a NACA M-12 on
 their P7
 series. You may want to leave the wing scaled down less than the
 fusaloge. Hopefully the DXF files will have the airfoil
 elements plotted with
 the flap amd aleiron % of chord, if not the ordinates can be
 downloaded. I
 search ae.illinois.edu canard airfoils and use the reverse
 directory to find out what is used on airframes of similar
 designs, then the
 main list for the ordinates. Personally I like the Harry Riblett
 airfoilson the main wing, and Rontz on the canard.
 Have you got any idea what prop clearance you need at
 the rotation
 point on take off. I am thinking at the stall angle of attack of the
 canard something like 8" clearance. It is not as much angle as
 it seems
 since the incidece on the canard has 3 degrees more incidence The
 full size
 version has five blade props so you will likely need a minimum of
 threeblades with one RH and one LH to get the disk diameter scaled
 down to a
 workable size.
 We will need to know if the CNC foam cutting shop wants
 the airframe
 sliced into workable size pieces or would want it as a complete
 solid that
 he can devide up at his location. As I remember the depth of the
 machineaccomodates 20" deep sections and the width and length are
 something like 5
 feet by 20 feet
 When you start looking for Glass cloth you might want
 to call
 Steve Thayer at thayercraft.com in High Point NC. I get 73 inch
 wide from
 him which reduces the number of seams. He has 3 million yards on
 hand and
 probably that much more lost to the inventory system. They ride
 bicycles to
 check stock quantities. He is building a Cozy and flies a Cessna 175

 george grimes

 Do you guys have a shop picked out for making the mold Bucks?
 The cnc
 machine I use is
 able to cut 20" deep x 80" x 18ft long, longer if the mold can
 be put on an
 angle [depending
 on the o/a width of the buck but upwards of 20ft would be
 possible]. I'm in
 the process of
 getting a 5 axis head [head/head style] designed and built for
 it, should
 make building
 molds/bucks that much easier over my current 3 axis system.

 Interestingly enough, I've actually designed my own 'Piaggio'
 type aircraft
 but have never built
 it to date. I'll send some pics of the model later today.

 Jarrett Johnson

 Hi Jarret where are you located and could you forward some
 photos of the
 equipment

 Jean Prudhomme


 Jean, I'm located just north of the MT/ND boarder where it hit's
Canada [in
 Canada]

 I've not got any photo's of the machine here [I'm at my day job
right now]
 but I do have a
 Youtube membership where you can see it in action.

 http://www.youtube.com/watch?v=nQytmfvUc7M

 Also have a website at www.innovention-tech.com [which needs
updating one of
 these days as
 there have been alot more projects down the pipe than are listed
there :) ]

 I've got to get some actual pic's of my mill on the site at some
point. First
 I need to clean it up a bit.
 It's amazing how far 75 cubic feet of foam will fly, it
currently looks like
 I had a snow storm in the shop!
 I've actually just finished installing a large industrial type
cyclone w/
 HEPA dust filters so the snow
 storms should stop, once I get the electrical interfaced [on/off
controlled  by] the machine.

 Btw, I do have a pic here of my Piaggio design [which I'll
attach here]

 Best

 Jarrett


 Very interesting design and do you have some dimensions of your
design.
I am waiting for the 1/6 scale scad design dvd of PIAGGIO

I check on youtube and i also see a big rotor of Robotic CNC Solutions

on YOU TUBE http://www.youtube.com/watch?v=1JcvCZFG0L0&NR=1


Jean Prudhomme            

The model is 34ft span and 29 ft long.  I didn't really follow the Piaggio design
to closely, I've found in the past that more often than not, scaling an existing
design runs a person into issues, so in this instance it was pretty much a
ground up design, based on passengers and usable load.

Lots of Cnc vid's on youtube... I've been known to spend hours [waste hrs
is more like it] looking at stuff there... pass's the time while traveling at least :)

Jarrett