Why Every Toolbox Needs a Handful of Jelly Crimps

Regular readers will know that I love Wago lever nuts for making solid, reliable connections in household mains voltage wiring. But another connector that I find myself using a lot is the Jelly Crimp. In fact, I used one today to fix some broken wires in some doorbells.

Jelly crimps are a mainstay of telecom installations and repairs (at least here in the UK). I was introduced to them years ago by an engineer who gave me a handful of them, and I’ve been hooked ever since.

Too: How to Strip Wires Like a Pro (And My Must-Have Tools)

These connectors go by many different names, but they are best known as jelly crimps.

The “jelly” bit in the name comes from the fact that the ends are packed with a dielectric silicone sealant that both adds extra insulation and also makes the connection weatherproof.

Depending on whether you want to connect two or three wires together, they come in two-way (called UY) or three-way configurations (called UR), and they are specially Designed for joining solid core copper or aluminum telephone and communication wires. ,

Too: How to use heat-shrink butt connectors to fix broken wires

Along with the UY and UR configuration differences, there are also different sizes depending on the outside diameter of the wire you are going to connect using the jelly crimp. The regular UR and UY are for thinner 22-26 awg wires with an insulation outer diameter of 1.52mm, while the UY2 and UR2 sizes accommodate thicker 19-26 awg wires with a maximum insulation outer diameter of 2.08mm.

You’ll find a lot of different brands out there, and they can be hit and miss, and I’ve seen the cheap ones fall apart or have no gel at all. I have a source in the telecom business that keeps me supplied, but if you have to buy them online, I recommend going for the 3M Scotchlok brand.

I find two-way ones most useful, with a 100 Pack of UY and a 100-Pack of UY2 having enough to meet my needs.

They are easy to use.

You disconnect the cable, poke the ends all the way through (no need to strip the insulation), and press the button to lower them down and cut through the cable.

Also: How to Solder: Tools, Tips and Tricks to Get You Started the Easy Way

Very easy!

Their primary use is on telephone wiring, but I’ve also seen them used on alarm systems, doorbells, speakers, and other low-voltage applications. These connectors can handle up to 50V, so don’t use them at mains voltage in case someone – possibly you – dies.

The connections are highly reliable, and as long as they’re not submerged in water they’ll last for decades (and even submerged ones have longer lives in my experience).

there is one special squeezing tool you can buy for $15, If you twirl a lot it might make sense, but I find I can use my finger and thumb, or a pair Knipex Mini Waterpump Pliers to work.

Did I mention they are incredibly satisfying to “pop”?