Flat Fell Seam

 

Flatfellseam1.jpg (120179 bytes) Put the 2 panels face to face, so that what will be the 'outsides' are together and you are working on what will be the 'insides'.  Sew a single line of straight stitch along the sewing line, leaving the seam allowance.
Flatfellseam2.jpg (111745 bytes) Now open up the 2 pieces and put them 'outsides' down on the sewing machine, so the seam sticks up as shown.
Flatfellseam3.jpg (138570 bytes) Fold both pieces of seam allowance over to 1 side. (To the left in this example)(Bottom of this pic)  See pic 6 for thoughts on which direction to fold them.

Take the cut edges and fold them back to the sewing line. (To the right in this example)(Top of this pic.  I am using the foot of the machine to hold it in place for the pic.)

Keeping the edges of the seam allowance on the sewing line, fold the whole seam allowance over to the other side, giving a nice flat folded edge. (Over to the right again in this example)

Flatfellseam4.jpg (118806 bytes) The flat folded edge is where the second row of straight stitching goes.  With my seam allowance, and the double fold, I can sew the second row of stitches with the edge of my sewing foot on the original line of stitches.

Make sure you maintain some outward pressure on the 2 pieces of fabric otherwise you could end up with a 'baggy' seam.

Flatfellseam5.jpg (136304 bytes) This is the seam completed.  I am using the foot to hold it down for the pic.
Flatfellseam6.jpg (132228 bytes) This is the same seam seen from the 'outside' of the fabric which will be the outside of the kite.  If the fabrics are 2 different colours, I usually try and create the seam so that the excess fabric is on the darker fabric side, up to you.  Again, the foot is only being used to hold things still for the pic.
Flatfellseam7.jpg (125572 bytes) Here I'm trying to show the end on view of the seam.

Once you get comfortable using this technique, it is very quick and I usually fold the allowances over as I sew, without pre creasing.