With the airbrake installed in the RH wing, the D box has now been skinned and a bit of other skinning applied behind the main spar to the point where I have run out of ply again!!
However, more will available after the weekend & a softwood LE strip will be fitted & profiled, rather than try to bend ply around the LE.
Meanwhile, the RH wing has been refitted to the fuselage to check the fit of the aluminium sheet wing retainer which is epoxied into the root ribs & projects from the wing root. The tongue slides through a slot in the fuselage root rib during rigging & is clamped onto the fuselage top plate by an M4 bolt in a captive nut as shown below.
I have slotted the tongue to allow it to move away from the bolt in ‘extremis’.
Photo of retainer in the wing root also shows some of the balsa strip skin supports added behind the main spar (& other places) where skin panel sections are butt jointed.
Meanwhile, an instrument panel has arrived from Cliff at Laser Cut Sailplanes
Also, the 2nd brake mechanism has been made up, ensuring that it is a mirror image of the RH unit. This unit will now be fitted to the LH wing once the brake box width has been increased as for the 1st wing.
Not sure if I mentioned it on the first brake build, but I am using 1.6mm wire pins for the blade hinge axles, running in brass tubes epoxied into the arms. The actuation pushrod fits into an M2 ball link running on a 2mm axle epoxied into the arm crank. All of the above axle pins need to finish fairly flush to the mount in order to prevent a projection catching on an adjacent blade or brake box edge during operation.
I have now received an updated 3 view drawing which shows Jilles’ amended CoG position, which is 157mm behind the LE - so just as well that I reduced the nose cone ballast load before fixing it in place
- RH wing partially skinned
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- Wing retention method
- Retainer in wing
- Instrument panel