Excessive print failure rate with clogged nozzle

I’ve been using the bronze Filamet for several weeks now in my Prusa i3. I thought that I had found the “ideal” print settings for the filament and I can get successful prints. The problem is that it is inconsistent–about two in every three prints is successful so I have about a 33% failure rate. This is usually due to a clogged nozzle. I’ve tried a range of temps from 220 to 235 and printed successfully. In addition, I have tried slowing down the print speed, turning off cooling, adjusting the z-offset, limiting volumetric flow rates, and disabling retractions and still I keep getting nozzle jams about every third print. I’ve even been cleaning the hotend after every print. Anybody have any suggestions?

What size nozzle are you using?

With the copper I’ve found that about 115% flow rate, 234 degree nozzle temp, no retraction and print speed around 25 - 30 to be pretty reliable.

I’ve also done this on .4 and .6 but I imagine it’d be easier with the .6

0.6mm nozzle definately make it relatively easier. I am printing most of mine at about 230 degrees, only 1 mm retractions and fairly slow at that (20mm/s) and slight increase in flowrate at 108%, Having had many prusa printers in the past blocked nozzles are common on the mk2 and mk2.5 (not sure on the Mk3) even with straight PLA and was a key factor in my getting rid of my three that I did have. I would check that the hotend fan is spinning as fast as it should, they are little dust collectors and a slight decrease in performance in the fan has a big impact on blocked nozzles. Iif possible clean the fins of the heat sink, this is also a dust collection area. This fan and heat sink need to be optimal as they are fighting a lot of potential heat creep with this sort of material.

Best of luck - chasing blocked nozzles is the worst part of 3d printing.

I battled clogs constantly at the start but it’s been getting a lot better (just printed 400g copper with no issues at all). I am using the creator pro with the 0.4 mm all metal hotend kit from micro swiss. I wish I could say exactly that it’s one thing but it’s probably a combination of settings and hardware!

One thing I might check is if your ptfe tube is frayed at the end.

Getting a smooth flow from the very beginning of the print is also important. If my bed is too close or too far and it starts to shmear or doesn’t come out of the nozzle, the entire print will have problems often.

Random ideas:

Try lowering the temp even more to 210 or even less. when the print finishes?

Make sure you don’t have “coasting” enabled for the end of the print? it’s important for the filament to kind of constantly be flowing; I’ve seen clogs for glass at least if Ieave it hot without extruding.

If you’re getting jams and/or blobbing on tall objects like a cylinder, try printing two at once to give it time to cool?

And as @3DEasy says it could always be a heat creep issue too.

Good luck, I know it is frustrating!

I second the nozzle diameter question… if .4mm (or smaller) go up to .6 at least and see how that works for you.