Working on Chapter 13 - Step 10
updated: 25/11/2010
Step 4
– Installing the Box Assembly onto the Fuselage
The M19 drawing is not very clear on the actual shape and size of Bulkhead F-0, so I used the Featherlite supplied Nose cone to mark the shape of the F-0 bulkhead onto a piece of 0.25in thick; tan medium-density H100 PVC Divinycell Foam. Wicks part No. F500-055. I marked centre lines on the foam, front & back, before proceeding with applying the single layer of BID onto the aft face. At this point I did deviate from the plans method for attaching the F-0 bulkhead to the assembled NG-30 panels. With the F-0 bulkhead flat on the bench top, the one ply of BID still wet and the NG-30 edges floxed, I carefully placed the up ended panels onto F-0, using the centrelines to ensure everything was nicely centred. The 2-ply BID tapes were then applied inside and out, peel plied and left to cure.
After cure I trimmed the edges and moved onto marking out and cutting the F-5 Bulkhead. I did not use the sizes provided in the plans as they are incorrect, since recommendations were made to widen the NG-30 panels. I took the measurements for F-5 directly from the assembled NG-30's.
Before moving onto mounting the NG-30 assembly onto the fuselage, I carefully checked that the fuselage was still level from front to back. There is not a lot of options for clamping the NG-30 to F22, so this is what I did:-
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I used a 1/2" drill bit inserted through the aft hole already drilled through the NG-30's for the rudder torque tube and using two clamps securely clamped NG-30 against the F22 bulkhead. This can be seen in the attached photos.
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I also clamped a piece of straight 1"x1" wood underneath the fuselage to ensure that the NG-30 panels lined up nicely with the bottom of the fuselage.
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I then cut a piece of wood the same size as the inside dimension of the two NG-30 panels and clamped this to the F22 bulkhead. The NG-30 sides were then clamped to the wooden block.
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I also placed a trestle underneath F0 and shimmed to ensure the whole assembly remained level.
Using the centre line already marked on the Front nose wheel strut, which I installed before moving onto mounting the NG-30, I checked to ensure that the NG-30 assembly lined up with the centre lines on the bottom of the fuselage, as well as F22. With all the clamps in place it is almost impossible to flox and apply the Bid tapes in one operation, so I decided to flox the NG-30 to F22 first and let cure over night. The next day all the clamps were removed and the 2x Bid tapes applied.
