I was getting very similar problems from a similarly aged Replicator 2. I think the problem is to do with heat creeping up the filament causing it to melt higher than anticipated.
Do you have thermal paste between the heat sink and block? That might help.
A more powerful fan could also help as it will more efficiently cool to be heat sink.
You could also try lowering your extrusion temperature. If it is lower there will be less heat creeping up the filament and therefore less chance of it jamming. I got some success with dropping my temperatures.
I recently upgraded to a E3D V6 hot end after getting too annoyed with the amount of failed prints I was getting. This has completely solved the problem, I’ve not had a single jam since.
Clean also the tube-part (that goes through the heater, sorry dont now the english word) above the nozzle. And try if the filament goes through easily. Had the same problem last month and my tube-part was dirty with plastic particles.
Hi, I just had the same problem last week! I spent a lot of time doing the same experiments as you did. The solution: by the new tube plus heater plus nozzle. Replace that parts. Level the plate. Print. Keep with the old heater for future maintenance.
Problem: inside of the tube part starts to be rough and then during prints the filament starts to stuck into this microscopic elevations given yielding to the clog effect. I highly recommend to replace those parts and do not waste to much time on experiences. (3D Printer Nozzle Clogs, Effects & How To Fix Them - YouTube 30).
I’ve had a similar problem, in my caso with Replicator 2X and ABS. I’ve done all sort of experiments, and cleaned everything.
What has worked for me is using a little amount of oil over the filament. Just wetting your fingers, and passing them over a 10-15 cm of filament, between the extruder and the spool.
I have to repeat it about each 10-15 hours of printing.
There’s a couple of things I can see as potentially being the problem here.
1. Partial block of the barrel and nozzle. One of the simplest ways to clean this out is heating it up and using a toothpick, dunking it in and pulling it out until it comes out clean. May need multiple toothpicks, be careful not to break them by applying too much pressure. Also look up the Atomic Method and try a variant where you heat the nozzle up, push through some normal PLA, let it cool slightly and pull back out. See if there’s any residue attached. I wouldn’t recommend the full atomic method that is used for UM2’s as it’s a different build.
2. Potential heating issue. When you mention that the PLA is hard and brittle when you pull it out, I get the impression that it’s cooled off. It may be that you need to make sure your heating block it getting to the right temperature.
3. Related to #2. Might be the other way around and you’ve got heat creep. This will cause the PLA to expand as it enters the barrel and cause it to stop extruding. In this case I’d check to make sure the main cooling fan at the front of the extruder is functioning as it should. If there’s broken blades on it, accumulated dust or age/use causing it to slow down or not function optimally this will impact extrusion.
4. Check the insulation around the heating block. It can degrade very badly over time and use as some of the plastics can stick to it. I replaced mine with automotive exhaust manifold insulation (thin ceramic plate wedged between metal sheets) and it’s never worked better.
5. Make sure everything is aligned in your extruder assembly. May not impact as much as the others, but it has affected my prints in some way in the past, though in conjunction with other issues, so I wouldn’t consider this a primary cause.
I’ve run a Makerbot Replicator 2 for over three years with 3300+ print hours. If running well, these machines will never die. For the last two years I’ve had a 99% success rate once I’d learned the cause and effect of most issues.
it’s a common issue. I had the same with replicator 2x . the problem was telated to 2 issues. the filament, too old and really rigid. you can break with fingers. and the second cause was the drive block that feed the extruder. It has a really smaal spring that with time loose strenght. check on thingverse a drive block upgrade. I ve designed one that can use the spring from a peg. and works perfectly using the old parts of the originak drive block.
I had the same problem as Andy explained I lowered my warmup temp to 200c and my print temp is 220c or less. Haven’t had any problems since. (also replaced the heating block at the same time as dropping the temp to make sure no extra goop inside would mess with it)
