Brief Description: Part 4: Router method for inspection hole parts
Note: The actually date for this was 11/26. I had to change the date to manipulate sequencing for multiple logs for this date.
I was doing some practice cuts in some scrap in preparation for cutting the wing panel holes. I was using the normal method of drilling the corners with a 1/2" bit then marking and cutting to within 1/4" of the line. After filing the excess off for longer than I care to file anything I got to wondering if the router method could be used on the panel holes.
I decided to make a jig and do some practice cuts. I made the jig the same way as the ring jig except that the outside of the frame did not need to be trimmed. I used a bigger piece of MDF to help support the wing skin better. After several successful practice holes I felt comfortable enough to try it on the wing skin.
To prepare for the router cut I used an extra hole cover that I had made and drilled a #40 hole at each corner radius 1/4" from the edge. I then drilled and clecoed the template to the hole location on the skin panel and marked the edges. Then the template was removed and the corners were drilled with a 1/2" forstner bit using the #40 holes already drilled. Then I used the dremel cutting saw to cut to within 1/8" - 1/4" of the line.
With the hole rough cut the jig was placed under the panel and the corners in the hole were used as a reference to position the jig properly. The router cut out is about 1/32" larger on each side than the template so all you need to do it make sure each corner is inside the jig opening. Once carefully positioned press the panel firmly onto the double sided tape. Very slowly run the router around the jig making sure to hold the router firmly and steadily.
This method made absolute perfect cuts that required no filing and the cover fits perfectly with 1/32" clearance all the way around.
