I will collect here what I know about medieval hand sewing and how it applies to sewing Venetian clothes. Sometimes I am quoting, rewriting or adding to my class handout on hand sewing. NB! The handout is in Adobe Acrobat format.
The sources I have given are on the web for easy access. They are all based on books on extant material.
i. Threads and needles
In our period there were three kinds of thread used: linen, wool and silk. Seams on wool fabric could have been sewn with any thread, but silk was sewn only with silk thread. Linen could be sewn either with linen or silk.
Extant needles* are relatively thick and long, made from copper alloys, iron or bone. For ease of sewing I use many kinds of modern needles: millinery, cross stitch, darning, embroidery and beading needles. If you sew a lot, the comfort and needle suitability for the seam at hand becomes really important. The rule of the thumb is: if you can do more than one stitch at a time, use long needle; one stitch at a time – short needle.
* The extant needles I have seen range from Viking age to 16th century. None of them are specifically Venetian.
Is the easiest and fastest stitch. Can be used as the main seam stitch, for decorative top stitching or the first seam stitch in flat felled seams. Needle: long and thin (millinery, darning or beading needle).
Is used to make a larger piece of fabric fit to a smaller one. Work two lines of running stitches close to the edge of the fabric, pull on the threads (gathering the edge) until it fits the given measurement. Needle: long and thin (millinery, darning or beading needle).
Overcast stitch aka whipstitch
Can be used as the main seam stitch, both seam stitches in flat felled seams or for overcasting the seam allowances. Needle: short and sharp for linen, dull for wool.
Can be used as the main seam stitch in stress areas or the first seam stitch in flat felled seams for extra strength. Needle: short and sharp for linen, dull for wool.
Hem stitch is a variant of overcast stitch. Used to tack an edge down. Needle: short and sharp for linen, dull for wool.
Pad-stitch is a variant of overcast stitch. Used to tack together more than one layer of fabric. Needle: short and sharp for linen, dull for wool.
Flat felled seam (running+overcast)
Useful for fabric that frays like thin wool, thick silk or linen.
Right sides together, running stitch 1 cm from edge. Cut one selvedge to half and fold both selvedges to that side. Fold wider selvedge under the narrow one and overcast the edge.
Double fold and hem stitch
Used on thin wool, thick silk or linen. The double fold protects the fabric edge from fraying.
Fold the fabric edge twice and use hem stitch to tack the folded edge down.