At our last guild meeting we had a meeting in my shop until almost midnight and I learned something new before the day ended from a couple of experienced turners. When you have end grain that will not stop tearing out in the lathe or real punky wood that may crumble when you hit it, you can stabilize it using Minwax Pre-Stain Wood Conditioner. You rough turn the bowl to a 1” or less wall . Then submerge the bowl in it for an hour or fill the inside of it and wait until you see it come all the way through to the outside. It takes a quart or more to do it but you can use over what did not soak in. Then let the bowl dry for at least a week before finish turning. I have often tried to fill bad areas with epoxy but wind up turning it all away to no advantage. This way the wood is stable all the way through .
I have two bowls in it right now and will prove it out in a week!......................Jim
-- Jim Jakosh.....Practical Wood Products...........Learn something new every day!!