Ive been thinking of making a simple wooden box with a door for hanging the wet 5x4 negatives in, something similar to my mockup below.

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On the top I was going to drill a hole in the centre and place a heppa filter over the hole which would be the intake.
On the bottom, I was going to drill the same size hole in the centre for the output.
Around the front where the door would close, I was going to place some draught excluder tape so the door would fit nice and snug up against it.

I am not overly concerned about force air or heat drying.

Question:
Can anyone see any flaws in this setup?