Looking for a home for a Diamond Machine wood lathe in working order. Will trade for bowl blanks.

Hi all. I’m new to turning and a recently joined member. I’m having a horrible time getting started. I’ve had 4 bowls go flying and ruined some pretty expensive wood!! One 12” maple bowl flew off 3 times. I attributed the first 2 times to my straight sided one way jaws so I bought a set of #2 dovetail jaws to get a better hold in the bowl. Next my 12” maple bowl went flying due to a broken tenon. I attributed this to the fact that I glued on a piece of pine to the bottom of the bowl to make the tenon and the pine broke. I assumed that the pine was just too soft and weak to make a strong enough tenon. Next I was working on an 8” African mahogany bowl and the tenon was turned integral to the bowl blank. That one broke too!! Another bowl destroyed!! It was a 2 1/4” dovetail tenon that was 3/8” long with a nice flat shoulder. I mounted it in my oneway chuck and made sure the tenon didn’t bottom out in the chuck and it was seated nicely on the shoulder. The bowl was turning true with no visible wobble. While working on the inside of the bowl with my 1/2” bowl gouge I was getting vibration whenever I cut even though I was going slow. Due to the vibration, I tried my brand new sharp round nosed carbide scraper and I was still getting vibration when cutting slowly. Then the tenon snapped off and the bowl went flying. I’m at my wit’s end and ready to give up turning!! Any thoughts? I’ll be at the next meeting and I’d be happy to have any advice I can get. I really want to do turning but I’m losing hope. I’d be happy to pay for someone’s time to come to my shop and help me figure this out. My email is Peter_Hicks@waters.com or you can reach me by text at 508-561-9566. Any advice would be greatly appreciated. Pete