Using magnetic drill for drilling holes in spar

My focus for the last few months has been to complete spar construction.Most of the holes were drilled and match drilled into the doublers using my mill to insure that the holes were perpendicular. However some holes near the root were left  deliberately left undone because of uncertainty in the plans. .Once the spar was clecoed together I had a better understanding of the hole locations and needed to drill those out.

Despite my best efforts it was not going to be practical to setup a fully clecoed spar in the mill. I also really did not want to disassemble the spars to drill the holes if I could help it. Hand drilling something like this is out of the question for me. I could not drill a perpendicular deep hole by hand if my life depended on.

Fortunately I have a magnetic drill press I had purchased for drilling holes in steel plate. It has just enough reach and clearance to drill the holes. I slid a piece of 1/4" steel plate under the spar, with appropriate spacers so the spar would not touch the very dirty and rusty plate. The drill was placed on the plate and the magnet turned on. I now have a quick and dirty drill press for drilling my holes in place on the workbench..

A few downsides with a magnetic drill for this case. The rpms are rather slow. It is really meant for making big cuts in steel, but it works quite nicely here for a few holes. I would not use it for drilling out rivet lines on the edges of an aluminum skin. Because the drill is geared down so low, it is also very loud. Hearing protection is a good idea when using. it.

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