Cold pull effect on nozzle
Is there any info regarding the effect of a cold pull on nozzle life? I'm using standard .4mm brass nozzles and I've replaced 3 through about 3800 hrs. I do a cold pull every 20-30 hrs or when changing from PETG to PLA. I print mostly PLA in various colors. It's more an inconvenience than a problem but I'm just curious. I don't use the acupuncture needles but I do clean the nozzle exterior with a brass wire brush.
RE: Cold pull effect on nozzle
Is there any info regarding the effect of a cold pull on nozzle life?
A cold pull is done at temperatures well below typical printing temperatures, so shouldn't cause any issues with wear. The only cautionary note I've seen is from E3D on their Nozzle-X series where they exclude cold pulls from warranty coverage of their nozzle coating (which seems odd).
[...] I'm using standard .4mm brass nozzles and I've replaced 3 through about 3800 hrs.
If you're getting over 1,000 hours out of a typical brass nozzle, that's pretty good.
[...] I do a cold pull every 20-30 hrs or when changing from PETG to PLA. I print mostly PLA in various colors. It's more an inconvenience than a problem but I'm just curious. I don't use the acupuncture needles but I do clean the nozzle exterior with a brass wire brush.
I do about the same, or whenever I notice any feed issues. I personally think the needles are far more likely to cause nozzle damage and avoid them myself based on personal experience. I'd rather remove gunk than just move it around in the hotend. The wire brush can also cause a bit of wear. Again, nothing for a brass nozzle but perhaps not good with coated types. I use a strip of corrugated cardboard to "squeegee" the nozzle and heater block clean.
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RE: Cold pull effect on nozzle
I do a cold pull every 20-30 hrs
I don't think that's going to cause any issues but I for one prefer to just run some length of cleaning filament through the hotend when switching from higher to lower temperature filaments. Less physical stress, and I haven't seen a clog in forever.
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RE: Cold pull effect on nozzle
I don't think that's going to cause any issues but I for one prefer to just run some length of cleaning filament through the hotend when switching from higher to lower temperature filaments. Less physical stress, and I haven't seen a clog in forever.
I do my cold pull with cleaning filament as the last step. Let it cool off and do the pull. I find the cleaning filament is nice and stretchy and won't snap off.
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He is intelligent, but not experienced. His pattern indicates two dimensional thinking. -- Spock in Star Trek: The Wrath of Khan
RE: Cold pull effect on nozzle
Thanks for the response. I was thinking about a hardened or coated nozzle but changing nozzles is pretty simple. I've also been thinking about cleaning filament, as per the second comment.
RE: Cold pull effect on nozzle
I don't see how cleaning filament can damage or wear a nozzle any more than other filaments. It's quite soft when compared to the brass (or harder) nozzle.
I do use the needle as one of the first response steps when dealing with an occasional clog. I am very careful, however to insert cleanly in the opening, as not to nick the edges of the opening.
I did have one incident when I had a tungsten-carbide nozzle installed and I made the mistake of trying to use one of those nozzle cleaning bits to attempt to clear a suspect clog. The bit broke off within the nozzle and I could not force it out no matter what I tried.
I've ordered a new TC nozzle and will install it when I can take the machine down for a while for some PM and cleaning.