I've made the cabinet doors out of a solid oak frame and a 1/4" oak
plywood insert. The plywood is a little under a 1/4" and as you've
already guessed, they rattle when I close the doors on the self
closing hinges. It's a terrible noise. Any suggestions on how to fix
this?

I think adding silicon or the like to the backs fo the panels is going to be
the easiest solution, but you will still see a small gap between the door
frames and the panels when you open the door. If you're okay with this,
then I think the best solution is to try what others have suggested and find
a way to either dab some silicon or slip in some very small shims.

But, for another suggestion, what I like to do on door panels is to put
quarter-round molding around the inside of the panels. This adds a very
nice touch, snugs up the panels and hides any gap between the panel and the
door frames. Typically, the quarter-round is 1/16" less than the distance
between the panel and the edge of the door. If your doors are 3/4" thick,
then you'd make the quarter-round 3/16". Make sense?

Since your doors are already finished, applying the moulding will be an
issue. Perhaps you could use a cabinet scraper to remove the finish from
the exposed edges of the door frame. Not the panel though because you don't
want the moulding to get glued to the panels. That would be bad when the
panels shrink/expand from humidity changes.

This solution would be a bit of work, but would look the best IMO when done.
But like I said in the beginning, the silicon slution is probably the
easiest.

Mike Dembroge
Dembroge Woodworks

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