.7 nozzle and printing speeds

[stonewater]

hi everyone,

was trying to get my print speeds up so I put in a .7 nozzle. when I have the print speed above 50mm for layers and for infill the stock hotend does not seem to be able to melt the filament fast enough. printing abs at 240 degrees. slowing to below to 40 solves the problem. the hot end is thermocouple calibrated, it shows about 1/2 degree diff between the thermocouple on the meter and the reading of the thermistor in mattercontrol.

I am able to print faster with the .5 nozzle up t0 60 with no apparent problems..

is this something any of you have seen?

Tom C

[gestalt73]

Hey Tom,

So to verify, during your print, you're seeing the hotend temps drop to the point where the extruder starts skipping steps or shredding the filament, right?

You very well could be running into a limit of how fast you can extrude at a given temperature with the stock hotend.
There's 4 factors that would contribute: print temp, the nozzle diameter, layer height, and print speed.

So to find your limits, either slow the print down, or reduce your layer height to see what the hotend maxes out at.

The funny thing about large diameter nozzles and tall layers, is that I've actually had to print at a lower speed than you would with the stock nozzle.
I've tried printing at faster speeds and the results are too sloppy.

Switching between my E3D V6 and my Volcano, I can print outstanding perimeters at 40mm/s on the V6, but if I go above 20mm/s on the Volcano, things get sloppy and uneven.
But with the larger diameter and layer height, I can still crank out a model in 1/4 the time vs the stock nozzle.

[Mac The Knife]

A .7 nozzle can extrude almost double the filament that a .5 nozzle can.

[stonewater]

Hey Tom,

So to verify, during your print, you're seeing the hotend temps drop to the point where the extruder starts skipping steps or shredding the filament, right?

You very well could be running into a limit of how fast you can extrude at a given temperature with the stock hotend.
There's 4 factors that would contribute: print temp, the nozzle diameter, layer height, and print speed.

So to find your limits, either slow the print down, or reduce your layer height to see what the hotend maxes out at.

The funny thing about large diameter nozzles and tall layers, is that I've actually had to print at a lower speed than you would with the stock nozzle.
I've tried printing at faster speeds and the results are too sloppy.

Switching between my E3D V6 and my Volcano, I can print outstanding perimeters at 40mm/s on the V6, but if I go above 20mm/s on the Volcano, things get sloppy and uneven.
But with the larger diameter and layer height, I can still crank out a model in 1/4 the time vs the stock nozzle.

Yes I am getting to the point where the hobbed gear starts cutting into the ABS. interestingly enough it does it slowly, like the filament os gstting too thin for the extruder gear. if I release the extruder, and push down real hard it will push the clog out as it has been sitting for a few in the hot end and gotten hot. it will then continue to print for a bit and then slowly stop again.

if I turn the peek fan off, it will stay hot enough, but then the ABS creeps up the tube into the peek area and clogs.

last night I moved my print speed down to 40 again, 10 hr print no problems.....

my hope was that the nozzle would help some of my longer prints get shorter. running at 40 it cut 3 hrs off an 11 hr print, its better, but the larger nozzle also makes the print a bit less smooth.

Tom C

[Mac The Knife]

Have you upgraded the stock hotend by replacing the resistors with a ceramic heater?

[stonewater]

Have you upgraded the stock hotend by replacing the resistors with a ceramic heater?

no I have not. one thing Steve (partdaddy) has said is that the resistors don't catch on fire and the ceramic heaters "can" so I was hoping to not have to do that. I can it is an easy upgrade I have what I need to do it. but I would think if a .7 nozzle is sold by seemecnc it would perform ok. it does work but not at the print speeds I want. may need to get a volcano, but would like to stop modding my printer at some point my wife is a printer widow....

used to be only kitplanes, a rabid RC or model rocket hobby caused divorce, now its 3d printers and shapeokos and lazer engravers, and lost wax casting, so much to learn so little time.

barry is putting out cool stuff now too!!! I need 6 of pilots mounts, 5 more makerhive boards, a smoothieboard, geez.... I guess I will sleep when I am dead. and I am going back to school in the fall!

Tom C