Is there a crimp tool, or something, for when you're soldering leads to leads

Are there any tools or parts that help when soldering a free-floating component to another one, for example a resistor to an LED? Something that will make some kind of mechanical connection instead of just relying on the solder. I imagine someone has to make some kind of little sleeve or collar that you slide both leads into and then crush, but I've never come across anything.

Answer

There are butt splice crimps such as this Molex one which go down to 22 AWG. Or this Amp one.

But the best way is a solder sleeve like this which is heatshrunk onto the pair of wires. The solder melts at the same time as the sleeving shrinks.