09/03/2008 - Wing Access Plates

Great something different to play with; the wing access plates.  3 per wing and situated on the underside of the aircraft, they provide access to critical element like bell cranks and things that require inspection and maintenance.

Job one is preparing them so that the edges are all deburred and smooth.  The holes that attach the plate to the spar are drilled to size #6 and the rest around the perimeter are drilled #8 and then dimpled to the same sizes to allow for the screws.

Now comes the tricky bit again and there are various methods for countersinking the #6 screw holes, but I stuck to the method I used for the large fuel tank attach points by using a piece of angle to locate the centre of the pilot for countersink.

Step 1, pic 1. setup countersink to correct depth < 0.312" in diameter
Step 2, pic 2. identify the right bits to drill, lol!!!
Step 3, pic 3. center the locating hole and clamp the aluminium angle
Step 4, pic 4, whip crack away !!!!

If all goes to plan and after riveting the plate nuts on then the access plate can be tested. Not sure whether I have the best fit or not from 2nd photo, maybe I need to take another look at the depth of the countersink

Anyway I managed to do another set of plate nuts before calling it a day.  Only 4 more access plates to go !