My IQ is not enough to conclusively solve this by myself, so here I go...

I have an antique piece of furniture that has 2 doors of unequal size on the front, depicted in green. The doors used to sit in a rectangular opening which with time became a parallelogram, depicted in red in the diagram. The angles are exaggerated, but accurately reflect the direction of the tilt.

I have a suspicion that this was caused by sitting on an uneven floor for decades which twisted the whole piece. Plausible?

And then is it possible to slowly twist it back by wedging 1 or 2 corners that sit on the floor? Where with time and gravity it would take original shape.

 

That could work -- but if it took decades for the twist to happen, it might take decades for it to straighten out.

There are lots of ways you could apply the needed torque to undo the twist. A lot depends on the particulars of the piece of furniture, its material, condition, strength, etc.

 

Put a clamp between the bottom left and top right corners to apply gentle but firm pressure. Then steam well on the inside with a boiling kettle. Close it up and let it dry out for 24 hours.

 

That's an interesting trick with the boiling kettle. It would sure speed up the process. I was fine with it sitting on wedges for 10 years to straighten it out naturally. I just can't decide which corners would need to be propped up. Probably 2 opposing corners, so then there is only 2 possible combinations.

I was thinking about not a clamp but a piece of wood wedged inside pushing it into shape. But then if it holds shape after some time, perhaps I'm fixing only one dimension. Maybe an uneven flood caused distortion in multiple dimensions and only wedging bottom corners in an opposing way would fix all dimensions.

What I'm having trouble with is visualizing in my head if an uneven floor could have caused the opening to parallelogramize. Which corner or corners would have had been resposible for causing that shape.

 

Are you sure that it was ever square? I made a gun rack in high school with a couple of doors on the compartment on the bottom and they started out with a similar mismatch because the frame wasn't quite square.

 

That's an interesting trick with the boiling kettle. It would sure speed up the process. I was fine with it sitting on wedges for 10 years to straighten it out naturally. I just can't decide which corners would need to be propped up. Probably 2 opposing corners, so then there is only 2 possible combinations.

I was thinking about not a clamp but a piece of wood wedged inside pushing it into shape. But then if it holds shape after some time, perhaps I'm fixing only one dimension. Maybe an uneven flood caused distortion in multiple dimensions and only wedging bottom corners in an opposing way would fix all dimensions.

What I'm having trouble with is visualizing in my head if an uneven floor could have caused the opening to parallelogramize. Which corner or corners would have had been resposible for causing that shape.

If you use a wedge, make it top left to bottom right. Wedge it near the front unless it is distorted the same at the back. Then wedge it half way back from the front. Distort it a little bit more than what you need to make it square again because it will spring back a little when you remove the wedge. It may take a couple of tries. Don't worry too much about making the whole cabinet perfectly square, as long as the doors fit properly again.

 

Are you sure that it was ever square?

I would imagine so. It doesn't have wear on the frame where the doors rub, so it probably was straight at the beginning of its life when it was actually used as intended. And then it became an antique decorative piece where the doors weren't used, hence no wear.

 

Put a clamp between the bottom left and top right corners to apply gentle but firm pressure. Then steam well on the inside with a boiling kettle. Close it up and let it dry out for 24 hours.

Yes, clamps are the way to go. Once you get it 90-deg, you can consider reinforcing the angle by gluing some small blocks in the interior corners.

 

"All about wood"

 

My IQ is not enough to conclusively solve this by myself, so here I go...

I have an antique piece of furniture that has 2 doors of unequal size on the front, depicted in green. The doors used to sit in a rectangular opening which with time became a parallelogram, depicted in red in the diagram. The angles are exaggerated, but accurately reflect the direction of the tilt.

I have a suspicion that this was caused by sitting on an uneven floor for decades which twisted the whole piece. Plausible?

And then is it possible to slowly twist it back by wedging 1 or 2 corners that sit on the floor? Where with time and gravity it would take original shape.

View attachment 339343

Why not just use a shelf cross on the back side ?