
Help with fabric in a shadow box holding stained glass
So, this is a weird one. I am trying to make a shadowbox for a piece of stained glass a family member made for me. I don’t have a proper window for it (vinyl windows and I live in a basement). I found an off the shelf shadow box that will fit it beautifully, and have placed a hook near the front of the box where the glass is. What I’d like to do is run lights behind it so I can illuminate the glass. My idea was to line fabric behind the stained glass, get it taught and staple it in then have enough of a lip behind the fabric to run the strip lights on the side and back of the shadow box. My issue stems from being able to successfully do this without the fabric looking like total crap. The corners don’t look great, there are waves from where I got one area tight and others not as tight. Is there a better way to do this?
Maybe frosted matte white plastic? I’m not sure. I’m going to try again soon and would like some advice.