A simple replacement plastic clip for an insulin pump pouch.
The pouch and clip are rather expensive to buy, the lady who the item was for was happy to sew her own pouch but needed a quick way to make the plastic part that clips on to a bra strap
The cloth pouch is worn under the clothing and holds a device which is about the size of a mobile phone.
Step 1: Collect Materials and Tools
You will need.
A sheet of plastic, I've used ABS 2.5 mm thick (polycarbonate would also be suitable)
A scalpel or craft knife
straight edge or rule
a vice or clamps
a few bits of metal plate or wood to act as heat shields and/or bending jigs
Hot air gun
Wet and dry paper
Step 2: Cut the Plastic
The ABS is soft enough to cut with a craft knife, it can even be scored and snapped to size with the edges being cleaned up a later stage.
In this case I've cut my strip to 10mm in width to copy the original clip.
Take care with the scalpel!!!
Scalpels were designed to cut flesh, guess what they are really good at cutting.....?
Step 3: Clamp the Plastic
Place the plastic between two bits of metal and clamp them in the vice, the thinner piece will be what you are folding the plastic over (so its thickness will become the depth of the bend) and the thicker one at the back acts as a heat shield
you're going to do the smaller bend first that's the one on the inside of the clip.
Make sure you have clamped the plastic square (at a right angle) to the metal that's holding it.
Step 4: Heat and Fold
Now using your hot air gun slowly heat both the front and the back of the plastic you've left protruding from the bit of metal.
When the plastic becomes soft wrap it around the thinner piece of metal. A third bit of metal or even wood is used to push the plastic forward and down over the jig in a rolling motion, hold it in place for a moment or two so that the heat can disperse and the plastic solidify.
Note. don't over heat the plastic as it will easily burn.
Step 5: Clamp the Other End
Now unclamp the assembly and reclamp it so that the smaller bend is at the bottom.
As you can see the piece of metal I was using as a heat shield in the last step happens to be the right thickness for this bend it also was the right width for the body of the clip.
I've used the side of the vice so i have plenty of room for the excess plastic to wrap over the jig.
Again the plastic is heated and folded using the same motion as before.
When the plastic is cool slide it off the jig.
Step 6: Trim and Finish
Now cut the excess material away.
You will find that the heating and folding has caused some distortion at the bends this splayed effect can now be cleaned up on a bit of sand paper.
I then used a small file to radius and tidy the cut end, finally I've used a scalpel to break the sharp edges and radius the edges.
Step 7: End Result
A little crude but fast and cheap.