Need help with a couple of items

[wardroom]

Hi all

I got these two items in a recent purchase of bits and pieces, I am having senior moment with how to use the centre finder.
Also what would the second picture be used for.

Thanks in advance.

 

[woodyturner]

The center finder if you have an 8" bowl blank cut to the round you simply line up the hole and the ark to the edge of the blank and draw a line along the stright edge then repeat again across that line and were the two lines cross that is the center
The other tool is used in conjunction with a deading / parting tool to create a correct size spigot

 

[jpt]

The second item is a sizing tool best explanation is look HERE

There are 2 uses for the centre finder firstly it can be used to draw circles on wood for cutting out. You put a nail through the hole near the point at the bottom then choose what size you want and put a pencil through that hole and draw your circle.

Not sure about the centre finder bit though it looks a bit odd, does any part of it move?

john

 

[CHJ]

I thought the centre finder was for use on the ends of square spindles much the same as I do with pen blanks.