I was not planning to fool with this drain hole right now,� but thought it might be a good idea while we were talking about it.
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I gave myself 1 hour to make an attempt,� to avoid using a bunch of time when I should be working on the floors.� haha
My first thought was to use a piece of hard maple as a "hammer form",� and maybe fasten it to the inside,� with screws from the outside.� �I figured wood would be easy to shape.
Then I came across a piece of 1/2 steel with some holes in it.� �I have been wondering how the plasma cutter would do with 1/2" steel (its advertised max),� so decided to try to cut out a form.� �Photo below is the starting point.� �
(well not the starting point, but photo is after a V-notch was cut for clearance from the vertical brace)
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The cutter did fine on the V-notch,� so decided to proceed with cutting the oval.� �Below is photo with the form after cutting,� �plus the other tools used.

The center was cut out� . .� starting with 2 holes.

The form was clamped to inside.� �I was not sure this would be secure enough,� but it seemed� to work fine.� �� Started by tapping with 1/2" ball-peen,� �the switched to smaller body hammer.� �The lips were still not formed enough,� so the wedge was used to force the opening wider.

The inside does not look perfect,� �but for this build is fine.� �If I decide to later,� but might try to make the inside radius a little smaller to look more stock.

From the outside,� I am very happy with the results.

It ended up taking over 1.5 hours,� but I wasted a lot of time,� at least 20 minutes of that was grinding and fitting that V-notch.� �I am glad I did it.� �One more task done.
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