I have a hand operated Mitre saw, although I have sliding bevel power saw, the hand operated unit is still useful for coving, cornice & plinths.
This model is a "Black Forge Deep Cut Precision Mitre Saw" ... bought form B&Q some years ago. But looks identical to this:
The blade is tensioned by turning a wing nut which 'pulls' a stud through the handle casting .. other end of stud has a cross pin to the blade.
Today found that wingnut and stud threads are worn, and I can no longer tension blade ...
So need to get a spare ... but can't find "Black Forge" on Google .... anybody have contact details ? Original box & manual give no address.