My CTC can't print very fast because it will skip steps, and also I can't have retract too high, because the grip on the filament will slip, even though I have upgraded the extruder with a spring loaded one. Yes better results, but I still have to have the retract rate pretty low so it does not lose grip. I have noticed other printers can have retract rate at 60 without losing grip, so I was wondering why this is so? My extruder grips so well if I hold it with my fingers it will still pull, and I don't think it skips steps at all now it just on the retract, but I think that's a problem with a hotend, which I am upgrading now.

My question basically is how can some printers have such good retract abilities? Which printer has the highest reliability and performance in your opinion as far as retract rates go. It's probably a question of the hotend design as well. Is a spring loaded replicator type drive the holy grail and the problem is basically the hotend? Is the heat zone simply too long on a replicator so warm filament gets retracted into the drive? I'm just looking for what the best hotend and extruder is so I can study it. I might eventually replace the entire extruder assembly on my CTC.