Continuing on from Part 1, this time I am only altering the front pattern piece by lowering and widening the neckline. And using a double band that is stitched down at the neckline. 

Steps:-

Figure. 1  

Trace off the front pattern piece using either paper or a lightweight sew in interfacing and draw in the shoulder seam stitching line. For this example I have folded Flair Pattern 1001 front pattern piece in half.

Figure. 2  

Measure down from the Centre Front neckline 3.5cm (1 3/8") and draw a line 2cm (3/4") long then next measure across from the Centre Front 7.5cm ( 3") and draw a line, these lines will act as a guide for your new neckline.  Draw in your new neckline using either a French curve or the original front neckline pattern piece. 

Figure. 3

The new neckline will be your cutting line, so draw in your stitching line by measuring 1cm (3/8") from the new neckline edge (no need to add seam allowances as the pattern piece already has the seam allowance added). Note that the front pattern piece has been folded in half.

Figure. 4

Measure the back and new front neckline stitching lines - shown in navy (excluding the shoulder seam allowances) this determines the length of your new neckband.

Figure. 5

The neckline band is a rectangle piece 5cm ( 2") wide by the length of your combined back & front neckline stitching lines plus 2cm (3/4").  And to reduce the back seam thickness, I use a mitered seam to join the band.  

For those who have the Flair Pattern 1001, use the neckband binding ends to draw in the mitred seams. Otherwise see below for the instructions to create a mitre seam.

Figure. 6

To create a mitre seam for the left side - measure 5.5cm (2 1/8") from the bottom left hand corner and mark in, next draw a line from the top left side to the marked point, this now becomes your stitching line. Next draw in your cutting line by marking in 1cm (3/8") outwards from the stitching line.

To create a mitre seam for the right side - measure 5.5cm (2 1/8") in from the top right hand corner and mark in, next draw a line from the bottom right side to the marked point this now becomes your stitching line.  Next draw in your cutting line by marking in 1cm (3/8") outwards from the stitching line.  

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I encourage you to have a go at creating your own neckline by first doing a sample piece using some scrap knit fabric, that you have at hand and testing the neckline band before doing a full T-shirt.  Let me know how you go!