Thomas - My father was also a Marine. He fought in WWII at Iwo Jima. I just recently built a flag case for his flag. I got my plans out of a recent issue of Woodsmith magazine. I will look tonight and see which issue that it was in. It was fairly recent, maybe within the past 6-8 months. I finished mine inside and out with polyurethane. I never thought about it, but I think that as long as you use any type of finish that hardens, you should be OK.
When they folded your father-in-laws flag, did it end up with 4 stars showing? I have heard that this is how a display flag should end up. I have mine folded now with 4 stars, although slightly crooked. I have one star at the peak and then 3 stars along the bottom edge.
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