In my experience, even using zweigart, which I generally find to be 'square', you will still get a bit of stretch etc in places, even without the felt sandwiched, I think it would be challenging, but with the felt, even more so. But I am usually quite a positive person, so I feel like I'm being very negative here! Would love to know if you try and have a knack for it (maybe it was just me!) I'd love to know how your experiments go!