Can anyone tell me where i am going wrong?
I am trying to finish a wonderful <ahem> 3 dimensional wing shaped brooch.
I have managed to solder the 'feathers' onto the base, both of which consist of thin (1mm?) silver.
But when i try and solder a thicker strip of silver (4mm) it just won't stick! the solder won't flow at all. Is it because i am trying to stick together metal of different thickness, so its not heating through at the same rate? if so what can i do about it? everyhtin else seems okay - enough solder + flux and everything nicely cleaned....

Ideas??