I’ve had such problems (ABS printing) until doing a complete renew of some parts of my Replicator 2X.
I think it’s an insulation/refrigeration problem and the cold end of thermal barrier is overheated. First of all I think my old fans couldn’t cold enough. My machine has about 1000 use hours. The only way to print was to open door and remove plastic top cover. But frecuently this didn’t work. In a few words, overheated, the thermal barrier transmits the heat up to the cold end, filament begins to expand being its diameter higher than the inner thermal barrier so filament gets stuck inside the cold end and don’t get down to fuse inside the nozzle.
As I had a broken thermocouple as well, the I decide to renew the following components:
It does. The heat break is right above, and could have a small clog. I can’t remember if you have an all-metal heatbreak, but if you don’t, the PTFE liner tube in the heatbreak could need replacing.
I have a Replicator 2X and after a lot of printing, I had the same problem. It is probably the nozzle. The best solution I have found is the plated nozzles from Performance 3 D. They have 3 different grades of nozzle. The basic Elite series seem to work very well.
Order 0.4mm for the default size. If experimenting you may want 0.5mm for Flexible plastics. Or 0.3mm for trying ultra smooth high resolution parts.
Another step I took was to increase the length of the area of the thermal barrier tube that is a smaller diameter. This smaller diameter is to reduce the heat conduction. Making it longer improves the heat barrier effect.
The same supplier has replacement filament tubes, also called thermal barrier tubes. They have 2 styles, step drilled and straight through. I would choose straight through.
The steps for you to follow might be a) Order a new nozzle and a spare. b) Drill out the existing filament tube that is clogged and very carefully clean it by making the drill rub against the sides. c) Order a thermal barrier tube. It is plated with the same plating as the nozzles.
I recently had to take these very same steps to repair a Replicator at a public library. They had tried to get it fixed for 18 months. It is now printing just fine for hours at a time. So the nozzle is the key.
High there. my name is Musashi an I use my MakerBot 5th gen everyday all day.when you say replicator 2 are you saying the 5th gen or the dual extrude version 2x? which nozzle type are you using? the regular extruder or a Smart Plus. How old is the nozzle an how many hours has it used? Do you play with retraction settings at all? These questions all play a small part in me being able to answer you better to the best of my knowledge.
I printed 1500 hours last year an went through 4 nozzles. this year I’m at 900 an have used 1 nozzle. Bad filament can shorten your life on it. I have stuck to using MakerBot, Inland, and Shaxon filament.