Thinner Filament. Greetings to All of you! [b]Do any of you heard of a filament (PLA in particular) that is thinner than 1.75 mm? Is it possible to purchase it somewhere?[/b] I can't get away form the idea of developing very light weight direct drive extruder paired with 0.2 mm or even smaller nozzle. It would be nice to print small parts with higher resolution. I am aware that few tried forcing standard filaments through smaller nozzles. Most efforts were somewhat unsuccessful, due to significant strain on the extruder (and other factors). Thank you in advance for any information. https://reprap.org/forum/read.php?1,834126,834126#msg-834126 Mon, 07 Sep 2026 08:53:00 -0400 Phorum 5.2.23 https://reprap.org/forum/read.php?1,834126,834535#msg-834535 Re: Thinner Filament. https://reprap.org/forum/read.php?1,834126,834535#msg-834535 The NEMA14 smaller size also allow a more compact extruder.]]> MKSA General Mon, 24 Sep 2018 09:24:25 -0400 https://reprap.org/forum/read.php?1,834126,834530#msg-834530 Re: Thinner Filament. https://reprap.org/forum/read.php?1,834126,834530#msg-834530 It is much lighter than the standard direct drive of my Prusa i3. ( ~350gram less )
I found an interesting datasheet for it, which indicates that almost full torque is available from ~75RPM to 525RPM.
Spinning slower than 75RPM is a real 'downer'.
[attachment 107153 17HS08_torque.JPG]

I also have a NEMA14 pancake with 50grams plus weight of the cycloidal gearbox. That one needs a redesign regarding bearing diameter and idler clamping.]]> o_lampe General Mon, 24 Sep 2018 07:30:13 -0400 https://reprap.org/forum/read.php?1,834126,834521#msg-834521 Re: Thinner Filament. https://reprap.org/forum/read.php?1,834126,834521#msg-834521
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o_lampe
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MKSA
Anyway, buckling becomes the real killer and one has to reduce the distance from hobbgear to melt zone. This is why I don't like the E3D kind of attachment, heatbreak and heatsink that became the standard and made my own far shorter.
Here is my direct extruder. The filament path can't be much shorter. It's driven by a 1A/13Ncm NEMA17 pancake. ( forgot the exact weight )
The 28BYJ you might recon' was a fail.
[attachment 107151 2018-03-2715.46.14.jpg]

That is the standard MK8 with NEMA17. It can be slightly shorter with a geared extruder and therefore a smaller motor, NEMA14 Of course a lot lighter too. Never tried a 28BYJ as if was obvious it couldn't do the job. NEMA14 is the smaller stepper one can use.]]> MKSA General Mon, 24 Sep 2018 04:59:58 -0400 https://reprap.org/forum/read.php?1,834126,834510#msg-834510 Re: Thinner Filament. https://reprap.org/forum/read.php?1,834126,834510#msg-834510
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MechaBits
Sorry if I missed them in other threads (o_lampe), but what did prints look like, how often you use it, on what kind of parts.

Unfortunately the extruder to make the filament is on the same printer as the 0.8-extruder itself. I ran out off filament and would have to refit the Make-extruder again. There was no big interest in the subject back then, so I didn't print much more than proof of concept stuff.
The drive gear with shrink tube was the only issue left.]]> o_lampe General Mon, 24 Sep 2018 00:31:30 -0400 https://reprap.org/forum/read.php?1,834126,834509#msg-834509 Re: Thinner Filament. https://reprap.org/forum/read.php?1,834126,834509#msg-834509
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MKSA
Anyway, buckling becomes the real killer and one has to reduce the distance from hobbgear to melt zone. This is why I don't like the E3D kind of attachment, heatbreak and heatsink that became the standard and made my own far shorter.
Here is my direct extruder. The filament path can't be much shorter. It's driven by a 1A/13Ncm NEMA17 pancake. ( forgot the exact weight )
The 28BYJ you might recon' was a fail.
[attachment 107151 2018-03-2715.46.14.jpg]]]> o_lampe General Mon, 24 Sep 2018 00:22:46 -0400 https://reprap.org/forum/read.php?1,834126,834499#msg-834499 Re: Thinner Filament. https://reprap.org/forum/read.php?1,834126,834499#msg-834499
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JoergS5
Besides welding I found the possibility of galvanic 3d printing, but it's very slow.

... to give you a hint into this direction - think about drastically speedup (or slowdown) galvanic or etching reactions with lasers ;)]]> VDX General Sun, 23 Sep 2018 17:23:56 -0400 https://reprap.org/forum/read.php?1,834126,834496#msg-834496 Re: Thinner Filament. https://reprap.org/forum/read.php?1,834126,834496#msg-834496
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VDX
... sorry, can't post more details or images as it's again an R&D project wit NDA's 8-)

I understand. Good luck with it!]]> JoergS5 General Sun, 23 Sep 2018 16:36:42 -0400 https://reprap.org/forum/read.php?1,834126,834494#msg-834494 Re: Thinner Filament. https://reprap.org/forum/read.php?1,834126,834494#msg-834494 VDX General Sun, 23 Sep 2018 16:15:25 -0400 https://reprap.org/forum/read.php?1,834126,834487#msg-834487 Re: Thinner Filament. https://reprap.org/forum/read.php?1,834126,834487#msg-834487 MechaBits General Sun, 23 Sep 2018 14:31:38 -0400 https://reprap.org/forum/read.php?1,834126,834485#msg-834485 Re: Thinner Filament. https://reprap.org/forum/read.php?1,834126,834485#msg-834485
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VDX
... not powder - think about melting/fusing thin wires with the laser ;)

Could you please show a picture or give my a youtube hint?

I know the HRL video, but this is powder imho.

=> I found your info on [reprap.org]
It is an interesting solution. The combination of different manufacture methods seems to open a lot of possibilities.

Besides welding I found the possibility of galvanic 3d printing, but it's very slow.]]> JoergS5 General Sun, 23 Sep 2018 14:21:50 -0400 https://reprap.org/forum/read.php?1,834126,834481#msg-834481 Re: Thinner Filament. https://reprap.org/forum/read.php?1,834126,834481#msg-834481 VDX General Sun, 23 Sep 2018 14:05:16 -0400 https://reprap.org/forum/read.php?1,834126,834478#msg-834478 Re: Thinner Filament. https://reprap.org/forum/read.php?1,834126,834478#msg-834478
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MKSA
Done for metal using plasma, laser, ion beam deposition.
VDX mentioned his current work, laser plus "plastic" filament.

You mean laser plus metal powder? I mean melting metal (heat up with induction e.g.) and printing without laser.

Laser plus thermoplast is used at the FastFFF, it is a good idea.]]> JoergS5 General Sun, 23 Sep 2018 14:02:00 -0400 https://reprap.org/forum/read.php?1,834126,834446#msg-834446 Re: Thinner Filament. https://reprap.org/forum/read.php?1,834126,834446#msg-834446
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JoergS5
I am thinking about whether it's possible to press the melted filament into the nozzle with other measures than the extruder.

If melted material can be pressed by e.g. Argon to avoid oxygen reactions, you could make overpressure or underpressure to control the melted filament flow.

The reason I am thinking about this is to think about printing aluminium.

Done for metal using plasma, laser, ion beam deposition.
VDX mentioned his current work, laser plus "plastic" filament.]]> MKSA General Sun, 23 Sep 2018 06:07:21 -0400 https://reprap.org/forum/read.php?1,834126,834440#msg-834440 Re: Thinner Filament. https://reprap.org/forum/read.php?1,834126,834440#msg-834440
If melted material can be pressed by e.g. Argon to avoid oxygen reactions, you could make overpressure or underpressure to control the melted filament flow.

The reason I am thinking about this is to think about printing aluminium.]]> JoergS5 General Sun, 23 Sep 2018 04:45:41 -0400 https://reprap.org/forum/read.php?1,834126,834437#msg-834437 Re: Thinner Filament. https://reprap.org/forum/read.php?1,834126,834437#msg-834437
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o_lampe
That's why I chose 0.8mm filament. It matches 1mm ID Teflon tube. I was lucky to get a tube with 2mm OD. It fits inside the normal PTFE-heatbrakes.
It also needs proper guidance between gear and heatbrake to avoid spaghetti.

IMHO the chamber pressure can be much lower, since the cross-section of 0.8mm filament is so much smaller than 1.75 or even 3mm.
I had no problem with 1st. layer adhesion, but I have LokBuild on my printbed. PLA almost sticks too good on it.

Chamber pressure depends mainly on the nozzle diam and the extrusion rate (at the nozzle !). Now, the filament diam being smaller, the pressure being the same, the force is indeed reduced (prop to the diam ^2) .

An other thing, the smaller the filament diam, the more melted filament will be leaking up the heatbreak as people usually (unless you have very accurate drilling equipment) drill 2/10 mm more than the filam diam. For 1.75 I drill to 1.8mm then smooth the hole.

Anyway, buckling becomes the real killer and one has to reduce the distance from hobbgear to melt zone. This is why I don't like the E3D kind of attachment, heatbreak and heatsink that became the standard and made my own far shorter.]]> MKSA General Sun, 23 Sep 2018 03:45:22 -0400 https://reprap.org/forum/read.php?1,834126,834428#msg-834428 Re: Thinner Filament. https://reprap.org/forum/read.php?1,834126,834428#msg-834428 It also needs proper guidance between gear and heatbrake to avoid spaghetti.

IMHO the chamber pressure can be much lower, since the cross-section of 0.8mm filament is so much smaller than 1.75 or even 3mm.
I had no problem with 1st. layer adhesion, but I have LokBuild on my printbed. PLA almost sticks too good on it.]]> o_lampe General Sun, 23 Sep 2018 01:58:49 -0400 https://reprap.org/forum/read.php?1,834126,834416#msg-834416 Re: Thinner Filament. https://reprap.org/forum/read.php?1,834126,834416#msg-834416 MechaBits General Sat, 22 Sep 2018 18:06:14 -0400 https://reprap.org/forum/read.php?1,834126,834373#msg-834373 Re: Thinner Filament. https://reprap.org/forum/read.php?1,834126,834373#msg-834373
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o_lampe


A finer pitch for the teeth would make sense, but reducing the diameter would cause more RPM for the same feed rate. Something like the Bondtech extruder would work. It would grip the filament from two sides.

A smaller diam also means less teeth contacting the filament. As a matter of fact I made a 12mm diam hobbgear (teeth made with a M3 tap) to get more grip. A lot simpler than the Bondtech approach :) Stays cleaner too !]]> MKSA General Sat, 22 Sep 2018 03:53:59 -0400 https://reprap.org/forum/read.php?1,834126,834362#msg-834362 Re: Thinner Filament. https://reprap.org/forum/read.php?1,834126,834362#msg-834362
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uticatechclub
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o_lampe
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uticatechclub
Could it be also true, that reducing existing drive gear by the same ratio achieved by reducing 1.75 mm filament to 0.8 mm filament would be good enough? Am I over simplifying?

I don't understand what do you mean with reducing the gear?

I mean making it smaller proportional to how much smaller in diameter the new filament became.

A finer pitch for the teeth would make sense, but reducing the diameter would cause more RPM for the same feed rate. Something like the Bondtech extruder would work. It would grip the filament from two sides.]]> o_lampe General Sat, 22 Sep 2018 02:01:19 -0400 https://reprap.org/forum/read.php?1,834126,834351#msg-834351 Re: Thinner Filament. https://reprap.org/forum/read.php?1,834126,834351#msg-834351 or some new cat gut variant? I know ppl have done it just not sure what the results where.]]> MechaBits General Fri, 21 Sep 2018 19:19:09 -0400 https://reprap.org/forum/read.php?1,834126,834344#msg-834344 Re: Thinner Filament. https://reprap.org/forum/read.php?1,834126,834344#msg-834344
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o_lampe
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JoergS5
It would be interesting to produce thinner filament on-the-fly from 1.75 mm or 3 mm filament, i.e. remelt into thinner filament before it moves into the hotend. This remelt should be done protected from oxygen.

That was partly my 1st. idea, but pushing still hot filament through a Bowden tube is a no_go.

Yeah, youd have to miniaturize a a machine that is normally heavier than a 3d printer in order to do that

But i bet you could get the same effect by machining a cone shape into a volcano nozzle for example rather than the parallel sides that terminate in a your desired tiny nozzel,]]> DaGameFace General Fri, 21 Sep 2018 16:31:37 -0400 https://reprap.org/forum/read.php?1,834126,834264#msg-834264 Re: Thinner Filament. https://reprap.org/forum/read.php?1,834126,834264#msg-834264
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JoergS5
It would be interesting to produce thinner filament on-the-fly from 1.75 mm or 3 mm filament, i.e. remelt into thinner filament before it moves into the hotend. This remelt should be done protected from oxygen.

That was partly my 1st. idea, but pushing still hot filament through a Bowden tube is a no_go.]]> o_lampe General Fri, 21 Sep 2018 04:47:29 -0400 https://reprap.org/forum/read.php?1,834126,834253#msg-834253 Re: Thinner Filament. https://reprap.org/forum/read.php?1,834126,834253#msg-834253
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o_lampe
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MKSA
The motor power required is mainly a function of the extrusion flow. If you reduce the filament diam., you will have to run at a higher speed to keep the same flow !

I'm not good at math, but I doubt that.
I agree that melting power is proportional to extrusion flow, but from my experiments I've learned that the filament diameter has a significant impact on required motor power.
The torque of a current controlled e-motor is always max at low RPM and stays constant upto 50% of it's max. RPM.
Max RPM is proportional to V_motor. At 24V this means it can run faster than usually required for a extruder. E3D Titan is a good example.

You are right, that it has to run faster, but I say: it doesn't matter.

I didn't say it is null, of course the thicker the filament, the less flexible it is and thus more force to drive it.
Still, (unless a poor hobgear and filament path)most of the force required is to push the filament in the hothend and extrude it through the nozzle. The thicker the filament, the lower its speed to get the same extrusion rate. Power is force X speed, torque X ω (in radians/s)
That means for a 3mm fil. you may have to use reduction gears to get the higher torque required. It is seen in 3mm extruder using Nema17 while the same motor can drive directly a 1.75mm. Steppers are a bit like gas engines, you need a gearbox to get its full power :)]]> MKSA General Fri, 21 Sep 2018 03:10:59 -0400 https://reprap.org/forum/read.php?1,834126,834243#msg-834243 Re: Thinner Filament. https://reprap.org/forum/read.php?1,834126,834243#msg-834243
You could
- change the filament diameter to fit your nozzle diameter and layer height, throughput
- mix filament with other filaments to get true color or material mixes anlogue to alloys]]> JoergS5 General Fri, 21 Sep 2018 01:40:55 -0400 https://reprap.org/forum/read.php?1,834126,834240#msg-834240 Re: Thinner Filament. https://reprap.org/forum/read.php?1,834126,834240#msg-834240
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o_lampe
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uticatechclub
Could it be also true, that reducing existing drive gear by the same ratio achieved by reducing 1.75 mm filament to 0.8 mm filament would be good enough? Am I over simplifying?

I don't understand what do you mean with reducing the gear?

I mean making it smaller proportional to how much smaller in diameter the new filament became.]]> uticatechclub General Fri, 21 Sep 2018 00:55:40 -0400 https://reprap.org/forum/read.php?1,834126,834238#msg-834238 Re: Thinner Filament. https://reprap.org/forum/read.php?1,834126,834238#msg-834238
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uticatechclub
Could it be also true, that reducing existing drive gear by the same ratio achieved by reducing 1.75 mm filament to 0.8 mm filament would be good enough? Am I over simplifying?

I don't understand what do you mean with reducing the gear?]]> o_lampe General Fri, 21 Sep 2018 00:15:04 -0400 https://reprap.org/forum/read.php?1,834126,834237#msg-834237 Re: Thinner Filament. https://reprap.org/forum/read.php?1,834126,834237#msg-834237
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MKSA
The motor power required is mainly a function of the extrusion flow. If you reduce the filament diam., you will have to run at a higher speed to keep the same flow !

I'm not good at math, but I doubt that.
I agree that melting power is proportional to extrusion flow, but from my experiments I've learned that the filament diameter has a significant impact on required motor power.
The torque of a current controlled e-motor is always max at low RPM and stays constant upto 50% of it's max. RPM.
Max RPM is proportional to V_motor. At 24V this means it can run faster than usually required for a extruder. E3D Titan is a good example.

You are right, that it has to run faster, but I say: it doesn't matter.]]> o_lampe General Fri, 21 Sep 2018 00:11:19 -0400 https://reprap.org/forum/read.php?1,834126,834210#msg-834210 Re: Thinner Filament. https://reprap.org/forum/read.php?1,834126,834210#msg-834210 research o_lampe!

Regarding your conclusions on drive gears and teeth:

May be we could make assumption (based on vast empirical work accomplished by RepRap community) that popular drive gears, their geometry and tooth configurations are quite usable with 1.75 mm filament.

Could it be also true, that reducing existing drive gear by the same ratio achieved by reducing 1.75 mm filament to 0.8 mm filament would be good enough? Am I over simplifying?]]> uticatechclub General Thu, 20 Sep 2018 15:12:36 -0400 https://reprap.org/forum/read.php?1,834126,834194#msg-834194 Re: Thinner Filament. https://reprap.org/forum/read.php?1,834126,834194#msg-834194
I just noticed the link in your post leading to your previous work - very interesting...
I will take a good look at your findings.]]> uticatechclub General Thu, 20 Sep 2018 12:10:32 -0400 https://reprap.org/forum/read.php?1,834126,834191#msg-834191 Re: Thinner Filament. https://reprap.org/forum/read.php?1,834126,834191#msg-834191
You nailed it in your last sentence: "Now if you are OK for a lower flow, indeed you can scale down everything. 3D pen use a very small motor, yet a 1.75 mm filament."

I am OK with the fact that print speed will go down to achieve higher resolution. And I am very much embracing the point of scaling down everything.


What bothers me with 1.75 mm filament in such application is that area representing nozzle opening shrinks very rapidly:

1.75 mm diameter represents area of 2.41 mm^2
0.4 mm nozzle opening provides area of 0.126 mm^2 --------------------------------------> ~15 times smaller
and proposed 0.2 mm nozzle provides area of only 0.031 mm^2 --------------------------------------> ~78 times (!) smaller


To obtain similar extruder dynamics (as how it relates to filament melting in heated space, retraction, pressure, etc.) one would want to keep the area relationship at ~15 (as shown).
It would imply that by using 0.2 mm nozzle and ~15 times area ratio, the new filament diameter must shrink from 1.75 mm to 0.77 mm.

Finding filament between 0.5 mm to 1.0 mm would make it very much feasible to experiment with higher resolution FDM.
I hope, I was clear enough to convey my point.]]> uticatechclub General Thu, 20 Sep 2018 12:02:36 -0400