jwws is right that Builder’s Hardware might be able to locate something that will work.
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I used to work in the boat building industry and I have a feeling the “part” you are looking for MAY be sitting in a marine hardware store.
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They make sliding rods for holding hatch covers partially raised. Kind of hard to explain – but in essence what you are doing is taking a piece of hardware designed for a vertical application and adapting it to be used in a horizontal mode.
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And if you would be satisfied with a solution that allows the top half of the door to be locked in a non adjustable open position (say 6″ open) then the solution becomes even easier.
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You will still be able to come and go as you please with the upper portion locked in relation to the lower portion.
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Feel free to PM if you want more info. Sounds like we are both Arbor Heights neighbors.
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