First let me apologise as I didn't take as many photos as I thought I started of with the log you see at the start of this post please note this bowl is end grain
Forgot to take a photo of the next stage but you will see the full shape in a later photo so I started by forming the outside shape I wanted including the foot and spigot to grip the bowl to remove the inside I didnt sand at this stage because it could all be done when I sand the inside as the whole thing is exposed and not covered by the chuck
I used the Robert sorby Sovereign system to hollow the bowl out which is designed for end grain work
Robert Sorby Sovereign Ultima System 22" it is a very good system and £100 cheaper than the roly munro and just as good once it was hollwed out I sanded the whole thing to 600 grit 2 coats sanding sealer and buffed with a cotton cloth 2 coats friction polish then finished of with woodturners stick
Now you can see the bottom which I forgot to photograph at the start the dovetail is 70mm to fit my chuck but it can be made any size to fit your chuck also note I left the original mark were the tailstock point went this is so I can remount it in reverse to clean up the foot
First you will need a wad of folded paper towelling to place over the chuck first close the jaws up then cover the whole chuck to offer protection for the inside of the bowl place the bowl over the towelling and chuck bring up the tailstock fitted with a revolving centre and engage it in the base of the bowl were it was right at the start and lock it down with some pressure on the bowl but not to much or you could split the bit of wood you left on for this stage start the lathe and remove the dovetail with a spindle gouge this will give you better access