You can't. You would be losing material when sawing, the amount depending on the saw kerf width, But you can easily thin your stock down to 1/8" thick on a belt sander or by hand lapping it on a sheet of coarse sandpaper. A table saw or bandsaw would make short work of thinning. Now if you had maybe 3/8" thick stock and you had a particularly steady hand and eye, maybe you could saw your material into two 1/8"+ thick pieces.