scroll saw collapsible basket advice

Hey All, When you cut a spiral in a board to make a collapsible basket, what is the preferred angle of cut to allow the edges to wedge together? Thanks in addvance,
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
Add image file
Upload is a website for homeowners and building and maintenance pros. It is not affiliated with any of the manufacturers or service providers discussed here. All logos and trade names are the property of their respective owners.