On Wed, 13 May 2020 14:40:33 +0100, "Jim GM4DHJ ..."
wrote:

Tried to put a new blade in mine today to cut some decking and couldn't
get it to stay in place...any ideas ? .... looks like a stupid
arrangement ....

Seems easy enough.

https://www.youtube.com/watch?v=rTZL2omZuGw