I have added another layer of glass on two occasions. Both times were first builds of new to me design and my swag was off. Figured I had nothing to loose, mine were way to light to cut off a couple of inches. I don't recall the beginning weight but mid twenties I think, I added .030 glass and turned out around fifty pounds. Still shooting well after several years. If you only need a few pounds I would try piking but, if not well, nothing to lose.