Although this is made from wood I hope to spark some imagination into your metal working. Or maybe you will try it in wood.
I made this Kaleidoscope for my wife 17 years ago for our 25th Wedding Anniversary. There is no finish on this peice. I sanded it to 1500 grit paper. It took longer to get the shine than it did to fabricate it.
Only two, American Cherry and Maple. You get the effect on the barrel by turning each segment 90 degrees. I picked eack segment from 5 seperate boards. There is no metal there either. It is held together by threaded dowels. Each of those knobs is also threaded.