Finding Smaller Diameter Nozzles

[oatfoundryprinting 0]

Hello Ultimakers!

I having been printing on my Ultimaker (V2 Hotend) for roughly 5 months, and I am more than pleased with the results I've been getting. My prints are quicker and I waste less time and material on failed prints than I did in the beginning - it feels good to progress!

However, recently I've run into some walls. I have been trying to print REALLY small objects for some customers, to no avail. The stock 0.4mm nozzle that came with the V2 Hotend is just too large to get these kinds of details that I need. In the past, for some small features, I've been able to tell the printer that I was using a 0.25mm head, without ever changing out my 0.4mm nozzle. Surprisingly, this trickery actually resulted in a decent quality print for what I needed, and did not over/underextrude too badly; the surface quality was there. Still, this manipulation of the software is only so good.

I'd like to get some smaller nozzles for my machine to tackle these REALLY small projects. My problem is that I have not been able to find 0.25mm nozzles (or anything in that range) that are compatible with my V2 Hotend setup. I ordered a couple nozzles from the UK that said they were compatible with Ultimaker, but the threads were too short for my heat block, and resulted in LOTS of messy leakage. No bueno.

So Ultimakers, where do you get your smaller nozzles? I am looking for something around 0.25mm to fit onto a V2 Hotend Setup. Any help is greatly appreciated!!

 

Many thanks,

Luc

 

[nick-foley 5]

Makergear sells them. They have a female thread, however, so you'll need to purchase the brass M6 tube they sell and either cut it down or replace the UM brass tube with it.

 

[gr5 2,099]

I ordered a couple nozzles from the UK that said they were compatible with Ultimaker, but the threads were too short for my heat block,

 

You can adjust a little bit - if you take it all apart (while hot!) - after removing the nozzle, screw the threaded tube further in from the top so that it goes further into the aluminum block (the peek part will be much closer and there will be a shorter cooling distance but it should be fine).

 

[oatfoundryprinting 0]

Thanks for the replies.

@Gr5: This is what I tried to do. I manage to unscrew it while it was hot, and threaded the 0.25mm nozzle onto the heat block. I then screwed the threaded tube closed, as hard as I dare without breaking it. I was presented with TONS of ooze, big globby messes running down the outside of my heater block and nozzle. Molten plastic was oozing out both the top AND the bottom of the heat block, where the threaded tube meets the block AND where the nozzle sits flat against the bottom of the heat block.

@NickFoley: Nick, with a female thread going into the nozzle, did you replace your entire brass threaded tube and just have one longer M6 tube going through the entirety of the heater block, into the nozzle? How did that alteration turn out for you?

I didn't know how I was getting so much ooze considering how tight I turned my new setup. Maybe I'll give it another shot. Anyone else run into these problems while replacing it themselves?

 

[nick-foley 5]

I replaced the entire brass tube. Printing seemed fine for several months, though I did replace that hotend eventually with something that was closer to stock when I got the parts in hand.

 

[msurunner 2]

I opened up one of my old nozzles from the V1 setup by taking a piece of heater barrel and screwing it into the old nozzle with a second nut to act as a captive force to allow me to remove it. The only thing you really need to be careful to do is to file little bit of heater bore flat and smooth to allow for a good mating surface.

 

[gr5 2,099]

Consider using some teflon plumbers tape. Other's have used this to help seal the threads in the hot end:

http://en.wikipedia.org/wiki/Thread_seal_tape

Apparently it can handle 250C no problems.

edit: teflon melts at 600K or 327C.

 

[pic299 0]

I have bought some putty for car-muffler mounting. It hardens at around 180°C and has a ceramic structure when hardened. It also withstands 300°C and more very easy. I applied it to the thread with a Q-tip (very very little). It is totally tight and there are no leakages whatsoever! And the stuff is very cheap. It costs around 8CHF (6 EUR) per package and I could seal approximately 1000 Ultimakers with it

brgds

 

[oatfoundryprinting 0]

Cool beans! Thanks for your responses everyone! It's giving me some good ideas on how to go about attacking this problem again.

One more question, if that isn't asking too much: Since I am shooting to print with a 0.25mm nozzle, do I need to print using thinner filament? Currently I use 3mm (actually about 2.85mm) filaments, and I was wondering if I HAVE to switch to a 1.75mm filament to print reliably with a 0.25mm nozzle? I have heard this change can cause some problems with extrusion, but is it necessary?

Additionally, if you switch to a 1.75mm filament setup, do you need to change the extruder drive in the back of the machine? I've heard that the UM1 extruder sometimes has problems moving 1.75mm filament. Anyone confirm or deny this?

Many thanks Ultimakers!!

Luc

 

[illuminarti 18]

I don't think you need to change to thinner filaments, particularly. You will be advancing the filament more slowly than with a larger nozzle, but at 800+ steps per mm, there's still a lot of headroom in the standard 3mm drive system for slow movements.

Everything about the printer stays the same, you're just squeezing plastic out of a smaller hole. The smaller the hole gets, the greater the force is needed for the same extrusion rate, so you will need to print much slower in order to not over-work the extruder motor. In general though, it should all work fine.

I don't recommend switching to 1.75mm filament with the standard extruder. Everything about it is geared up for the larger size. Some folks have run a smaller diameter bowden inside the standard one, but the grip at the motor end probably won't be as good, and the seal of the filament into the heating chamber wont be as good either.

 

[msurunner 2]

No you do not need to go to 1.75, just slow it down a bit.

I would echo illuminarti on switching to a different extruder if I was to go to a 1.75.

 

[oatfoundryprinting 0]

Thanks for your responses everyone! They have been most helpful!