In my attempts to come up with a hot end design that does not require an insulator, I came up with another way to make one that is cheaper, easier, and possibly more effective. This one is similar to my PFTE/wood insulator, but the wood in this case is an ordinary wine cork. The shape is almost perfect for an insulator, and the light, airy structure of cork wood should make it a more effective insulator.This requires an ordinary WOODEN cork from a wine bottle. I don't know what kind of plastic the plastic corks are made of, but it's probably not an appropriately high-temperature plastic.This is constructed just like the wooden dowel insulator, except that the drill hole is much smaller (about 3-4mm) so that screwing in the barrel will compress the wood, making it dense enough to hold the barrel tightly. It is also unnecessary to thread the PTFE insert, as the PTFE/cork thread interface will be useless. Just force the tube through the hole cork, then push it back by screwing the barrel in until it's secure. Cut off the excess and widen the end with a countersink bit and clear the hole with a 1/8" drill bit.This design probably won't work with a one-piece barrel/nozzle, because bits of cork get inside when you screw it in, and you have to be able to blow them out of the hole. This also won't fulfill my goal of making the insulator double as a bowden cable retainer, because the cork won't hold onto the PTFE well enough. Still, dollar for dollar, this is probably the most effective insulator possible.