I constructed a Small Built in Trophy Case. It's 30Lx50Hx6D. It's about 48 Inches off the floor. I made it in my basement, so I could remove it and get behind it for my gas meter and water shut off, kind of like a hidden compartment. Looking for a way where I can secure this and take it in & out easy. I was looking at some draw slides, Rv struts & Pocket door slide with hinges. I'm down to cutting 3 pieces of wood for the above the top & below the botton on angles (45 to the left & right with and piece in the middle matching) to be able to slide it in and out. Any ideas out there?

No problem Tommy.

No problem Tommy. Rick, That was inspiring, but what about my case? Any insight?

All depending on weight and material case is constructed of.

You can use by-pass door hardware mounted to wall above opening or you could use pocket door hardware mounted to the ceiling if case extends to ceiling. Either way you will need unobstructed wall space to one side.
You can hinge it (piano hinge) but case will only open to 90 degrees.

If it is light weight, and you want to lift and set it aside, you could use French cleat or key holes and screws.

I tried the "French Cleat" to slide it in and out, since the design is built in the wall. Something must be off square because it's a really tight fit and if the wife had to get to it, she wouldn't be able to move it.

Don't understand the
slide it in and out part, do you mean lift in and out?

Yes

Don't understand the part, do you mean lift in and out?

I constructed the case after I had framed out the wall and left an opening for it. My original idea was to have it hinged where I could pull it and it would swing open. (Didin't think of how to do this before construction) When I finally got around to it, I thought it would be easier to just have it slide in and out, which I tried to do with a french cleat. My mitre saw isn't 100% and the angles on the cleaat stick. My wife tried it and couldn't move it even though it only weights 20-25lbs. Just trying to get it in and out easier. Thanks.

Angles of cleats don't have to match, just have to be angled in correct direction and don't have to be all that sharp.
The cleats are naturally going to pull the case toward the wall from the weight. The sharper the angles the more the case will be wedged in. Remove one cleat and cut it more obtuse.

Angles A will have a tendency to get wedged in more than B or C. If you make the cleat on the wall a little thicker than the one on the case the case should hang close to but not touch the wall (at the top) and the case should not get wedged in.

C doesn't look all that good but will probably work the best. All the weight is suspended at one point and very little surface to get wedged.

Yprofes