Max nozzle size?  

Re: Max nozzle size?

I believe the Max nozzle size for these printers is 1.75, the same as the filament. Although, I don't know why you'd want to print that large.

Re: Max nozzle size?

With the standard heating arrangement, I doubt you would be able to print more than 0.8mm and even then only very slowly.

Have a look at the E3D volcano heater.

Peter

Re: Max nozzle size?

The nozzle sizes available (and recommended) for the e3D that comes with the printer are: 0.25mm, 0.30mm, 0.35mm, 0.40mm, 0.50mm, 0.60mm, 0.80mm.

They can all be used, just change the settings in your slicer of choice...

Re: Max nozzle size?

So I will try 0.8. But at what speed?

Re: Max nozzle size?

The V6 heater is apparently able to melt about 10mm^3/second.

Obviously that depends on the temperature you select and will define the maximum speeds.

You will have to test to see what works for you.

Peter

Re: Max nozzle size?

Interesting.

That would mean that the maximum speed with an 0.8mm nozzle printing at 0.8mm layer width and 0.6mm layer height (75% of nozzle width), one could achieve a maximum printing speed of 20 mm/s (assuming rectangular extrusion).

It also means that with a 0.4mm nozzle @ 0.4mm layer width, 0.3mm layer height and 60mm/s one achieves already approx. 75% of the maximum throughput.

Looks like installing a wider nozzle will not bring a lot in terms of reducing overall printing time, unless moving to a E3D volcano heater.

Am I missing something?

Re: Max nozzle size?

Actually the melt rate is slightly higher. From E3D:

11.5mm^3 per second is the max comfortable flow rate, you can go a little faster but extrusion is not as optimal

I limit the maximum flow within the slicer to 10mm^3/s to prevent any possible issues.

Obviously it is possible to push the temp higher, but during the slower or no extrude stages, there is a possibility of burning the plastic.

This first came to my attention almost a year ago with the Mk1 and Lite6 where E3D were providing only a maximum printing speed which I believed was a quite useless figure; I pushed them to do a melt volume test and this is what they came up with when using the V6.

Incidentally, it is possible to print line widths up to 20% wider than the nozzle width, so almost 1mm with a 0.8mm nozzle. This will add a little more strength to the printed model.

Peter

Re: Max nozzle size?

I have been printing 0.45 width and 0.25 height at 40 mm/s, that is 4.5 cm³/s, about half the capacity of the extruder.

With the 0.8 nozzle at about 1.0 mm width and 0.5 mm height, I can print at 20 mm/s. I need a volcano hotend. Damn, I just bout a new vanilla hotend 🙂

How come the Volcano has much higher capacity?

Re: Max nozzle size?

How come the Volcano has much higher capacity?

Because the heat block and cartridge are aligned vertically and the nozzle thread is longer.

The downside is that it won't fit the Mk2 without significant mods to the probe and part fan positioning and you will reduce the print height.

Peter

Re: Max nozzle size?

A 0.6 nozzle can print 0.7 width and 0.5 height. 11 cm³/s gives 31 mm/s.

Re: Max nozzle size?

Hmmm, so the real question is, if larger nozzle sizes limit print speed due to melt volume, what is the tipping point where increasing nozzle size no longer increases overall time to build a part?

Re: Max nozzle size?

That depends on selected printing speed, layer height, layer width.

I have made the following assumptions:
- max throughput is 10mm^3
- layer width = 120% of nozzle diameter
- layer height = 80% of nozzle diameter

This yields following maximum speeds by nozzle diameter:
0.4 mm-> 65 mm/s
0.5 -mm> 42 mm/s
0.6 -mm> 29 mm/s
0.8 mm-> 16 mm/s

So: above 42 mm/s, 0.5 mm nozzle won't work (with the assumed width/height), above 29 mm/s 0.6 mm nozzle won't work and above 16 mm/s 0.8 mm nozzle won't work.