thank you all.
I dont understand the Sally Collins method in this specific case. What does it help to make the first sashing wider if I have to sew at 3/8" anyway? And I cant make the blocks bigger (DJ) to have fabric under both sides ot the presser foot. Maybe I should buy the book as my imagination does not work on this one :-)
And sewing the two 3/8" sashings together first I would end up with even more layers on the left side attaching them to the block - wouldnt I?
I think I will try the zipper foot and see how it works.
Granny