thread line or grain line is any line thats parallel to the selvages (edges of width of fabric) and in patterns normally drawn as an arrow. Please be sure to put that arrow really parallel to the selvages, because only this way you can be sure it will fit and look as you want it to be.
deutsch: fadenlauf
español: recorrido del hilo
francaise: parcours du fil
italiano: corsa de filo
TailorFairy 
[…] The side edges of a fabric, mostly a little different looking and feeling then the bigger part of the fabric. Selvages don’t fray and are in the same direction as the thread/grain line . […]
[…] the fabric parallel to the selvage (grain line) then put the front template right at the fold, pin it and cut […]
[…] your fabric parallel to selvage/grain or in a right angle to it if its just a small piece, pin the ruffle-part right at the fold with […]
[…] fold the orange fabric selvage on selvage, and pin front and back of the middle to the folds and the sleeve-part next to it according to the thread line […]
[…] your fabric, selvage on selvage, take care of the grain line, my fabric is only 1.1m wide, if yours is wider it might look […]
[…] I folded the fake-leather selvage on selvage and pinned all parts I wanted to cut out of it in the right thread line […]
[…] draw the pant-parts on another paper until the knee line, dont forget to draw the grain-line on your new parts and add seam allowance to the […]
[…] Cutting (be sure you cut everything in the right grain line) […]
[…] place all parts on the fabric, pin straight to the grain line, I also put the vest/waistcoat parts on and cut, the wasitband needed to be cut in […]
[…] the parts on the fabric according to the grain line. front and back in fold, and if you use a printed fabric like me, be sure all parts have the same […]
[…] lines, same as the front marking for the sleeve and the back and the elbow-markings. but the grain line is more important then the fabric match, so be sure its always cut in the right grain. You […]
[…] half of the final piece and needed to be copied to the side, I cut them in a different angle to the grain line, to mix up the […]
[…] I placed all lining pattern pieces on the lining, minding the grain line. […]
[…] then I tried to place all pattern pieces on the fabric and when I found the right way I pinned them to the fabric, right with the grain line […]
[…] this, so 3 yards I ordered and then noticed they planned to cut the blouse in a right angle to the grain line and I planned to cut it with the grain (just looks better with my print) and I even used a little […]
[…] I pinned my pattern pieces to the fabric, carefully lining up the grain line. […]