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  • #852
    Brookes745
    Moderator

    After a nights drying the blanks were curved enough to be glued into place on the front decking, an easy job using cyano, and then the front faces cut to the correct angle…..

    #853
    Brookes745
    Moderator

    Next the leading edge piece attached….

    #854
    Brookes745
    Moderator

    And carved roughly to shape…..

    #855
    Brookes745
    Moderator

    Before adding the 1/2 inch top decking……

    #856
    Brookes745
    Moderator

    Time to think about mounting the motor. The model is designed to have 2 degrees of right thrust built in, this is to counteract torque reaction and is the same regardless of what type of propulsion you use (unless you use contra-rotating propellers like they do in F3A).  I decided not to build any right thrust into the fuselage by off setting the firewall, choosing instead to use an offset motor mount box. First step for this was to make a mount for the motor back plate out of 1/8 ply…..

    #857
    Brookes745
    Moderator

    Next the rest of the box was constructed while trying to add lightness where possible. This shot is looking into the box at the rear part that will bolt to the firewall…

    #858
    Brookes745
    Moderator

    To achieve the offset the box in 1/8 inch shorter on the right side and I’ve tried to show this here……obviously this is shown from below.

    #859
    Brookes745
    Moderator

    Finally the front plate placed in position but not yet glued as it will make life a lot easier later on…..

    #861
    Brookes745
    Moderator

    While wait for some longer M4 bolts and T nuts to turn up, I added a slot to the 3/8 ply firewall for cooling and to allow the motor cables to run and I also enlarged to centre hole to match the hole in the motor box. Shown here with the cooling slot marked up….

    • This reply was modified 1 year, 5 months ago by Brookes745.
    #863
    Brookes745
    Moderator

    This next shot shows the cutting done and some structure added to the top which will be part of the hatch retaining system…..

    #864
    Brookes745
    Moderator

    On to the hatch system. The front will be two locating dowels that will slot into a former incorporated it the structure mentioned above, attached to the hatch. The dowels are usually made from hardwood dowel but I didn’t have any of the right size so made some up using aluminium tubing with a hardwood core, shown here glued to the front of the hatch…..

    #865
    Brookes745
    Moderator

    And shown here from underneath in situ….the gaps will be filled later.

     

    #866
    Brookes745
    Moderator

    For the rear mounting, there are various possible methods such as magnets or a latch system but I decided to go for the same set up as was used on my Wind S, which is two retaining bolts, one each side of the fuselage. The bolts screw into T nuts on plywood tongues glued to the hatch. First off the holes in the fuselage were marked up, drilled and plastic sleeving inserted to make it more durable…..

     

    #867
    Brookes745
    Moderator

    Next the tongues were cut from 1/8 ply and the t nuts added…..

    #868
    Brookes745
    Moderator

    Slots were cut in the underside of the hatch which was then taped in place. The tongues were then offered up, adjusted so the holes lined up and tack glued in place….

Viewing 15 posts - 31 through 45 (of 112 total)
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