Here is a how the pack looked before I modified it.
The loops down the center of the flap are what I want to change. These vertical loops are usually referred to as a daisy chain. MOLLE, or more specifically PALS, is method of attaching pouches and equipment to a bag. It is used by the military and law enforcement personnel to attach things like radios, ammo clips, knives, first aid kits, etc to bags and vests. There are quite a few handy generic pouches as well. The PALS system uses one inch webbing spaced in horizontal rows one inch apart and sewn at one and half inch intervals. Most people seem to use the term MOLLE and PALS interchangeably but really MOLLE is a line of military gear that uses the PALS attachment system. Equipment that is attached using PALS webbing uses straps that are woven in and out of the rows and secured with a snap or velcro. Some equipment uses plastic clips that hook into the rows.
Here is a diagram of how to sew PALS / MOLLE.
Before I modified my backpack I first tried sewing some PALS webbing onto scrap fabric.
It went pretty well on the scrap fabric. The ends of the webbing were a little difficult because had melted them a little too much. When cutting the webbing you need to use a flame to melt the ends to keep it from fraying but it only needs to be melted very lightly. If you melt it too much it will cause big lumps which are difficult to sew. I did a test fit of my Leatherman sheath and it fit perfectly so I moved on to modifying my backpack.
The first step was to run a zigzag stitch across the rubbery material to hold it in place and to reinforce the strap before I shortened it. Then I used a seam ripper to remove all the stitching below the zigzag stitch. After that I used some scissors to cut off the strap and rubbery material from the area I want to place rows of PALS webbing.
Next I laid out the rows of webbing. I started out with laying pieces of webbing on the bag and measuring but it was difficult to visualize where the loops would end up. I made a paper diagram which made it easier to see how many full loops I could get. Because the flap tapers up I was only able to get three loops but that would be perfect for attaching my Leatherman and a flash light. Next I used a water soluble marking pencil to lay out the webbing and sewing line locations.
I trimmed the ends of the webbing to the same taper as the flap and lightly melted the ends. Then I pinned the webbing in place.
Next up was the sewing. The top piece of webbing wasn't too bad but the lower piece took some acrobatics to get all the lines sewn. I ran a straight stitch first and then a zigzag stitch over top of it for strength.
Sewing is complete. The stitching is visible on the inside of the flap but it doesn't look too terrible and the flap is usually closed. Quick test fit of my Leatherman and then all that's left is to clean up the white pencil lines with a washcloth and some water.
And here is the finished product. It turned out exactly like wanted. :-)
Just a small update. I sewed my own MOLLE flashlight holder out of some 2" webbing and added that to my pack. My buddy bought me a 'tactical' pen which fits nicely on the center loops.