The Amazon product links in this post are affiliate links. If you click on these links and purchase something, I will earn a small commission.
When I first started trying to make underwire bras way back sometime early this century, I learned of two options for re-tipping shortened underwires: Beverly Johnson at that time recommended Household Goop, and the book Sewing Lingerie that Fits suggested dipping the tips in a two part epoxy like J-B Weld. I used J-B Weld, since I thought it sounded like the better option – that stuff is practically indestructible.
With the recent popularity of bra making, it seems like everyone is using heat shrink tubing to cover the tips of cut underwires, and I haven’t seen any tutorials for using epoxy, so I thought I’d throw this out there as another option. I can’t say how epoxy compares to heat shrink tubing, since I haven’t tried using heat shrink tubing. When using epoxy you have to plan ahead since it takes a day to cure, but I’m happy with the results, and I don’t have to worry about the tips ever coming off, so I’ll probably stick with this method.
Here’s my method for cutting and re-tipping underwires:
You need to use large, heavy duty wire cutters. Don’t try to use your typical household needle-nose pliers – you might hurt your hand or damage your pliers! I use fairly thin gauge underwires, so my 9-inch pliers work OK, although I have to squeeze them fairly hard. If you are cutting really sturdy wires, have weak hands, or shorten underwires frequently, you’ll want even larger wire cutters.
You’ll also need a metal file and some two part epoxy glue such as J-B Weld.
Before you get started, make sure you have a place prepared to hang the wires while they cure, since you won’t be able to set them down once you get the epoxy on them.
Mark your wires where you want to cut them.
Place the wire cutters on a mark and squeeze part way down, place the wire and cutters under a piece of fabric, then finish cutting the wire. Underwires are made of spring steel, so when you cut them the ends go flying across the room, which is why I cut them under cover – I got tired of hunting for bits and pieces of underwire all over the place. If you don’t cover the wire as you cut, make sure you are wearing safety glasses.
Next you need to roughen up about 3/8″ to 1/2″ (10-13 mm) on the ends of the wires. If your wires are painted, use a file to scrape off the paint on the ends. If your wires have a plastic coating, cut around the plastic on the end, remove it, then scrape the ends with a file. You need to remove any residue or metal oxide and roughen the surface to make sure the epoxy will stick permanently, so scrape the ends with a file even if your underwires are not painted or coated. You don’t need to try to round off the sharp ends – the epoxy will cover those just fine.
Squeeze out equal amounts of each epoxy component onto a disposable surface and mix them together.
Use a Popsicle stick or something similar to spread J-B Weld onto the ends of the underwires. Work quickly, since the epoxy gets harder to work with as it starts to cure. Make sure you get plenty over the sharp ends, but you don’t have to try to get it perfectly smooth. The epoxy will smooth out a bit on its own, and you can easily sand or file off any extra lumps and bumps after the epoxy has cured overnight.
Hang up the wires to cure, and that’s it! Re-tipping underwires seemed like a lot of work the first time I tried it, but now that I’ve done it a few times, it doesn’t take me long.