"Today I set the Left and right spar up on the back tiled area of my house and prepared to line up the spars for the first time. I had some small pins made up of rivet stems that had been pulled already. I bent the tips of these and inserted them in the 3 alignment holes on the spars after having levelled the spars roughly on timber. I then checked the holes individually for light and symmetry downwards from above. Once satisfied I clamped the 2 halves together and rechecked them.
I then checked with a level the combined saprs and prepared to drill . I first did the centre hole and then put a temporary bolt through it and tightened it up. I then did either side alignment holes up to 3/16th size. Once happy with these, I proceeded with the wing attach blocks one at a time. I then up sized to 1/4 size on the 3 alignment holes and put a 1/4 bolt through each. I then proceeded with the wing attach blocks upto 1/4 size.
I then inspected the lowere side of the operation and all but one holes were perfect. One wing attach block had a slight ovaloid (?) section, I concluded from the initial drilling per the plans when making the assembly in the workshop. No problems I haveto undo about 8 bolts, 6 from the wing root attach angels ( which need to be removed anyway for the rib installation preparation.) and then the 2 block bolts. I will then remake another block of which I have plenty of stock. I will remake this and drill the 2 bolt holes but leave the wing through hole until it is re-attached to the wing. Once back on the wing I will just drill from the 'pilot' 1/4 hole from the other spar and the host spar of this block. This should allow a perfect hole clean through the block and save skewing again.
