Going "nuts" and 3D printing with a 1.0+ mm nozzle!
A ridiculously big 1.1mm nozzle make it flow like hell ! |
In fact, I had lost my smaller drill bit set made for smaller holes... So I took a brass cap nut, screwed it on a threaded rod, put it under my vertical drill press with a "regular" small drill, and here we go. I measured afterwards it to be something like 1.1 mm. Interesting...
Now for sure it was funny as a friend told me I just had made the first Scoubidou machine! But the first prints still were surprisingly good! Not only can I print very fa(s)t, but it still makes a nice print in the end.
Now, there were a few quirks I should have taken time to fix (see below), but very big nozzles are now part of my consideration when I want to prototype quickly and/or when the printed object needs no special accuracy: refining the ergonomics of a handle, or printing a toy and so on.
Testing it in real
Obviously with such a big nozzle, it makes sense to print fat also in the vertical plane, so I used a stunning 0.6 mm layer thickness. It also meant an amazing flow rate. I also asked for one pass walls: after all, they are already 1 mm solid as soon as the plastic is deposited!With a printing speed of about 100mm/s, I never saw my spool of 3 mm filament turning so quickly... I first thought I would be wasting a ton of filament doing something silly, but then realized that I would be asking for the same quantity of filament in the end as whatever nozzle size printing the same geometry... except that it just prints ridiculously faster!
It just prints unbelievably fast... and fat ! But after the good laugh, it proved not so stupid in the end! |
See? Of course you get coarser details than with a 0.3 mm nozzle where 10 layers may stack in each one of these, but as for rapid prototyping, you just cannot beat it! And the result is far from a joke : robust and watertight. And yes, this is yet another print of Cushwa's owl ! |
Now, the horizontal slight slopes are trickier, and I ran in trouble as my settings gave no chance to the printer to fill the required surface, as show near the feet below...
Some forgotten items, and a brief analysis
I had no flow issue at all beyond setting the correct value (I had no way to measure the nozzle diameter precisely). The Ultimaker heater block handled the flow easily and it was able to melt all the filament without trouble (I even printed slightly below the usual temperature). The prints were watertight except on my obvious mistake with the horizontal planes. I did not try enough before switching back to a normal nozzle but I think I may have been able to fix the bridges (note that it may be a bit trickier because of the weight of such a big extruded thread...)Also, I realize I should have tried retraction. But since I was printing with an almost viscous thread of plastic, here again I feel confident it can be made without special difficulty.
The other drawback, apart from the horizontal filling, was the cooling. As shown above, the part of the owl opposite to the fan produced wavy patterns because the filament had not enough time to cool down -- I think I reached my bottom limit of about 8 second per layer here, which was probably not enough. A second fan mounted to the opposite side would surely fix the issue.
Conclusion
I printed the owl at about 100 mm/s and I was very surprised to see how regular a flow I got, the Ultimaker doing its job very well. With a faster setup to change my hotend or nozzle, I would definitely consider this as a viable solution for printing sketches or quick prototypes. The resulting object is watertight and very solid also, with more than 1 mm thickness of PLA, I do not think I could crush with my bare hands.While printing hollow objects is attractive, the horizontal parts must be taken care of because it will have hard time to fill them with such a layer thickness.
Note that I printed only three items before getting back to a more serious business (such as tiny nozzles), but that was definitely worth the try!