Printable View
So I recently decided to try to print with a smaller nozzle diameter but I have run into a problem.
The filament extrudes somewhat out of the nozzle but after each extrusion step, there is a small thud sound and the filament looks as if it is being retracted.
I believe this is caused due to too much pressure building up in the extruder throat.
I have not had this problem with a 0.4 mm nozzle.
What could be the problem?
Are there any specific settings that must be changed to make it work?
Your layer height needs to be less than 0.2mm, best 0.15 or lower.
The main thing you come across with small nozzles is that because less plastic flows out, the heat spreads outside of the nozzle more and that can cause filament burns and clog buildups. So I recommend printing at a slightly lower temperature and higher speed as a start. And being very careful about which filament brand you use so the plastic is as homogeneous as possible and trustworthy additives/colorants.
The 0.3mm nozzles are a better tradeoff between speed and quality IMO.
For most purposes in my experience, a 0.4mm nozzle with 0.15 layer height already gives enough detail.
didn't say he was having any issues with buildup, so I will assume it's at the very start of a print.
With a .2mm nozzle there is a lot more back pressure on the extruder preventing it from, well, extruding. Try lowering the print speed and/or increasing the temperature of the hot end a bit. We have a similar issue with injection molding, only with the pressures involved shear thinning occurs and the plastic actually thins out, making it easier to force through the nozzle. Since 3d printers don't have the luxury of several thousand pounds of force at high speed, the only solution you have is to increase the temperature or use a filament with a higher melt flow rate (lower viscosity). Or just print much slower.
Lowering the temperature will make the problem worse.
You will however need better cooling, as ralph mentioned there is a fair amount more heat buildup around the nozzle when printing at lower speeds/extrusion volume. Printing out a fan duct that gives you more precise cooling will help there.
yeah I was thinking that.Quote:
Lowering the temperature will make the problem worse.
I usually up the temp a bit when printing faster. Just to get more plastic through quicker.
bear in mind that most pla has a printing range from 190 - 240. So upping the temp isn't a problem.
So for smaller nozzle just up the temp and slow print speed, it shouldn't burn.
But you said everything is different between molding and printing ;)Quote:
Originally Posted by curious aardvark
no - YOU said that :-)
I said the filaments used in 3d printing are different to the plastics you use in injection moulding. Which they are. Because you insisted on saying that if you couldn't do it in injection moulding you couldn't do it in 3d printing. Which you can because the processes and materials are different.
No, I was the one who was saying the whole time that there are a lot of parallels between the two.
lol - well yes. But differences as well.
But now you've got a printer or two - can we move on ? :-)
The horse is dead - stop flogging it .
And the materials aren't different at all by the way. They are consumer plastics, nothing more.