[cabinetman]

I have a few questions...

Since you don't want the 2 beds attached to the wall(s), how do you want them supported...legs?

When set up as 2 beds will they be in a straight line or "L" shape.

Can the 3rd mattress be stored somewhere when not in use?

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[cabinetman]

Here's an idea. Under the platform for the two beds, you have a full piece of ¾" plywood the same size. You make a track on the ends to carry the ends of the plywood, and an under guide for the long edges. When you want to add the middle mattress, you pull out both sections from the outer beds, and they meet in the middle. Half of the plywood is still supported under the two outer beds. The long guide on the long edges will carry the length. Where they meet, the two could be fastened (I'm workin' on that).

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