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                                                                             Another mile stone in the project!  In this chapter we build the

                                                                             first flying surface and get to cut some cores with the hot-wire.

                                                                                                

                                                                                       I’ll start right out by confessing that I cut my first canard
                                                                                       up and put it in the trash. I wasn't careless, it just didn't go 
                                                                                       well.  Often times on this project I’ll get discouraged or 
                                                                                       disappointed in how a part turned out, well maybe that 
                                                                                       happened once or twice... Usually the next morning the 
                                                                                       sun comes up, the birds start chirping and things don’t 
                                                                                       look too bad after all!  Well that wasn’t the case on this
                                                                                       one. I slept on it a few nights, talked it over with my wife
                                                                                       and …..tossed it. I have never regretted it. The second 
                                                                                       attempt went very well, the canard is straight and true
                                                                                       with  no twist and no issues to haunt me.

                            

 Here  are a few shots of the Hot wire saw, power supply and your’s truly making a cut. Notice the steady hand and steely nerves!  The power supply was found in a friends garage sale, another friend with a motor rewind business gave me the welder transformer .  I found about 25 VDC worked well for this length of cut. I used .032 safety wire and had no problems. I did have a few broken wires when using the expensive stuff ACS sells. The saw itself is simple to make, maintains tension regardless of temperature and you won’t break a wire if you forget to remove tension after a cut.. I used a #75 spring from the depot and a turnbuckle for initial tension. I would go for a stronger spring next time but this was adequate.     

                                         

                                 Here are some shots of the foam core cutting process, can you see how my wife could have gotten                                                    a hair cut doing this?



     

         

Next the leading edge of each cores are cut off just in front of the spar cap trough, the aft cores are set up on trailing edge and jigged straight using string lines and shims to get it perfect. Aluminum hardpoints for the lift tabs are installed, then the shear web lay-ups are installed. These lay-ups  go from spar cap face, over the front  edge and back over to the opposite spar cap face (trough).         

                                                                              

                                   

                                                                          

                                           Shear web lay-up complete, jigs are trued up using string lines and shims.      

                                                                                      

                                                                        

Leading edge cores are microed in place after attaching the lift tabs. I made my own tabs and used 3/16” 2024 T3 al. I wanted them a little beefier than  1/8”. I know 1/8” is more than adequate but if Nat was concerned  that we don’t even scratch them I figured a little more  material would be in order. Also gives me a  little margin  should corrosion ever get started.

                                                                            

Ready for spar cap glass. The shear web is visible here also.   Spar cap glass is placed in the trough. Getting all the plies installed without getting too high is the challenge here.  One tip for the spar cap glass I learned: Cut a block of wood to use as a squeegee, trace and cut the airfoil curvature onto the bottom of the block and use this to pack the fibers down.  Keep using it after peel ply and again after the masking paper is removed. At this stage you can check the spar cap contour and height against the foam core.  Works very well.

                                                         

 Here you see the bottom skin has been applied, peel ply is put down and wet out using epoxy
 brought up from underneath if possible.

                                        

Here you see the glass to glass bond area. Use care here to ensure you have adequate area for the glass to glass bond.  The 2nd pic is fill & finish using a sanding jig with the airfoil cut into it.

                                                                              

                                                                                       

Nav antenna is installed on top of the glass then covered with 1 ply of light weight cloth  from the hardware store. Look closely and you can see the BNC connector just aft of the lift tab. 

And I'm done with dis guy!                                    

                    

                                                             

                    

                                           

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