Sometimes you buy a nice dog collar that, though adjustable, is too loose even on the tightest setting. This happens to me often, as I need to replace worn or filthy collars used with our wireless electronic fencing system. Once our dog Indigo rolled in raccoon poop and the stink just could not be removed. The collars need to be wide enough to support the electronic unit of the collar, and often cannot be shortened to fit the neck of a medium or small dog. I discovered a way to solve this problem a couple of years ago. In this instructable I will show you how to shorten the collar and install the electronic unit.

Step 1: Cut the Stitching

Most collars with a plastic buckle have this same configuration. One end of the webbing is affixed to the plastic buckle and the other is attached to the slider. Use a sharp knife to cut the stitching on the loop attached to the middle of the slider, freeing that end of the webbing.

Step 2: Adjust Collar Length

Pull the newly freed end of the webbing through the the slider, tightening the diameter of the collar. If you have an old collar to measure with, use it to adjust the approximate size of the new collar. Cut off the free end of the webbing, leaving a couple of inches to spare so that there is still some room for adjustment. This configuration is self-tightening, in that tension on the collar prevents the webbing from moving through the slider. In most cases, you are now done. However, some collars have a smooth surface and will slowly loosen over time. You can in such a case readjust the size of the collar and with needle and thread sew the free end back to itself, reforming the loop. You only need a few stitches to keep it from slipping. Finally, prevent fraying by melting the cut end of the webbing with a lighter. Note: if you don't want to permanently shorten the collar by cutting off the end, you can keep the extra webbing under control with tape or velcro wrapped around the collar. We keep some collars like this for foster dogs, which vary in size.

Step 3: Optional: Install Electronic Collar Unit

Unscrew the electronic unit from the old collar and use the holes in it as a template to mark spots on the new collar with a marker. Use a wood burner or soldering iron to burn holes in the new collar and screw the electronic unit into them. The hot metal tool melts the nylon and leaves no frayed bits.