Wooden/Magnetic "Door Halfway-Open" Holder

This is a device to hold the door open halfway in breezy conditions. (It will not work in a high wind, but it works most of the time.)  We need to hold the door open when we are cooking, in order to ventilate the trailer.  We often do not want to open the door all the way -- too cold!  So this does the job without letting in too much cold air.

It is just a curved piece of oak lath (steam bent), with strong magnets at each end.  (I made an earlier version of this out of metal -- it was clunky and hard to deploy.)  It's curved in order to approximate the arc of the door jamb as it swings open -- a straight piece of wood would not do the job. (I tried it already.)

The magnets are on opposite sides of the lath.  One magnet sticks to the strike plate on the door frame, and the other sticks to the metal plate on the door that surrounds the bolt.  The magnets are taken from old computer hard drives.  The mounting plates already had screw holes, but I enlarged them slightly.

Here is the curved lath:

This shows how the magnets are attached to the lath.  The screws are very short -- about a quarter inch.  Note the green tape -- the ends are color-coded for convenience:

This is the inside end, which makes contact at the strike plate on the door frame -- note the red tape:

This is a view of the holder from the inside of the trailer:

And this is a view of the holder from the outside:

When not in use, the holder sticks to a small metal plate on the wall of the trailer, just inside the door.