First, I cut the thread at the top of the seam, and carefully pull it out down to where the bottom of the pouch will be. DON’T CUT IT OFF. Using the original thread, I work the ends in to the unaffected part of the seam, so they will not unravel.
Next, I get the new piece of leather wet, mold it around the firesteel and sheath, and trim it to size.
Then, I taper the edges of the pieces, to fit smoothly into the profile of the sheath, and use a stylus (or thumbnail) to mark the area that the leather will cover.
Before applying glue, it is important to dye the leather, if needed.
Glue (Barge Cement) is now applied to the appropriate areas, and ONE SIDE is stuck together.
Using the original holes in the sheath for a guide, I drill the holes through the one side of the pouch.
Now, I stick the second side down, and use the holes in the exposed side to facilitate drilling in the proper places. Now, I use the groover to cut stitching grooves, and sew the pouch down. I begin in the middle of the pouch, centering the thread in the hole–half the length on one side, half the length on the other, as is usual for saddle stitch. Using a single needle, I stitch down until reaching the uppermost hole that already has thread in it. Then, I turn around and come back up. When the thread runs out, I put the needle on the other half of the thread, and stitch up to the top and back down again, making sure that there is good overlap between the two sets of thread, so the ends don’t work loose.
As you can see, it is almost impossible to detect that there are two separate seams, except that the wax on the undisturbed stitching looks different.
Now, it is time to put the firesteel in the pouch. The leather should still be damp, so just jam it in there. It will probably go just a tad lower than it was originally, as the leather stretches.
Now, pull the firesteel out, and let the leather dry. Give it a good rub with leather dressing, and it’s ready to go!
Feel free to ask questions.