<p>Put it simply: they say 1.75&nbsp;mm with a &plusmn; error of 0.05&nbsp;mm.   Which means your flow may vary &plusmn;2.9&nbsp;% while you are printing creating blobs and such.  </p>

<p>The smaller the filament tolerance, the more expensive the production costs.</p>

CC BY-SA 4.0
2021-06-07T16:31:51.087Z
I'm curious how you arrived at 2.9% when I calculate +-5.7%.  The difference in surface area between maximum and minimum allowable diameter is 2.54 - 2.27 = 0.27mm^2.   Which is 11.4% maximum variance in extrusion volume or ~+-5.7% from nominal.  Have I done something wrong?  This is why I buy +-0.03 or +-0.02 filament.  They have 6.9% & 4.6% max variance respectively.  If I've done something wrong I may be paying more for less benefit than I think.
bielawski
CC BY-SA 4.0
2018-07-11T19:00:53.717Z
2019-07-26T08:38:13.663Z
2019-07-26T08:38:13.663Z
osirisstar
<p>Dimensional accuracy is not as important as dimensional uniformity. I can print with undersized (or oversized) filament, adjusting the flow appropriately, provided the filament has a consistent diameter. When creating filament in-house, without expensive equipment, it is difficult to maintain the same diameter throughout the entire extrusion. It is likely this extrusion diameter (when creating filament, rather than the output of the actual print head) to which Barafu is referring when he mentions his tolerances: +/- 0.05&nbsp;mm <em>in diameter</em>. Which is reasonable.</p>

<p>The "miniature printing" comment likely refers to printing miniature models for tabletop gaming.</p>

<p>If the source filament becomes wider than expected, the output will have overflow, or more material than desired will be deposited, and this will certainly affect the quality of the piece.</p>

CC BY-SA 3.0
2017-01-26T18:12:19.373Z
Perhaps I should adjust the question, then? I see most PLA filaments advertised as 1.75 mm (+/-0.05 mm).  Does this mean a variance of 0.05 mm in the diameter throughout the filament?  Or that the diameter is uniform, and it's within 0.05 mm of the advertised diameter?
LegendaryDude
CC BY-SA 3.0
2017-01-26T18:37:43.283Z
It could mean either, but most likely the first option. Your print head is likely tuned to accept a certain (small) range of filament diameters.
Davo
CC BY-SA 3.0
2017-12-20T02:33:33.057Z
@LegendaryDude - it means the first of the two (variance throughout the filament).  That number does not give you a degree of _certainty_ but a degree of _uncertainty_.  The cases where the filament may be constantly +0.05 mm or -0.05 mm from its nominal value are just "special cases" of the more general one.
mac
CC BY-SA 4.0
2017-01-26T18:05:06.023Z
2019-07-26T08:36:44.100Z
2019-07-26T08:36:44.100Z
Davo
<p><a href="https://3dprinting.stackexchange.com/a/2820/5782">In this answer</a> user <a href="https://3dprinting.stackexchange.com/users/4345/barafu-albino">Barafu</a> says,</p>

<blockquote>
  <p>Yet I manage to keep my tolerances +- 0.05 mm which is enough for everything but miniature printing.</p>
</blockquote>

<p>I have asked for clarification on that answer regarding what is meant by "miniature printing" but in the meantime, I want to ask the general question.</p>

<p>What impact does dimensional accuracy of filament have on final print quality, and why?  Does it vary between different filament types? </p>

<filament><filament-quality><dimensional-accuracy>
How important is the dimensional accuracy of filament relative to the detail of a print?
LegendaryDude
# How important is the dimensional accuracy of filament relative to the detail of a print?

(Asked by: username_0 on 2017-01-26)

[In this answer](https://3dprinting.stackexchange.com/a/2820/5782) user [Barafu](https://3dprinting.stackexchange.com/users/4345/barafu-albino) says,

> Yet I manage to keep my tolerances +- 0.05 mm which is enough for everything but miniature printing.

I have asked for clarification on that answer regarding what is meant by "miniature printing" but in the meantime, I want to ask the general question.

What impact does dimensional accuracy of filament have on final print quality, and why? Does it vary between different filament types?

**Tags:** filament, filament-quality, dimensional-accuracy


---

## 2 answers

### Answer by username_3 on 2017-01-26. Score: 5 | Accepted answer

Dimensional accuracy is not as important as dimensional uniformity. I can print with undersized (or oversized) filament, adjusting the flow appropriately, provided the filament has a consistent diameter. When creating filament in-house, without expensive equipment, it is difficult to maintain the same diameter throughout the entire extrusion. It is likely this extrusion diameter (when creating filament, rather than the output of the actual print head) to which Barafu is referring when he mentions his tolerances: +/- 0.05 mm *in diameter*. Which is reasonable.

The "miniature printing" comment likely refers to printing miniature models for tabletop gaming.

If the source filament becomes wider than expected, the output will have overflow, or more material than desired will be deposited, and this will certainly affect the quality of the piece.

> **Comments:**
> **username_0**: Perhaps I should adjust the question, then? I see most PLA filaments advertised as 1.75 mm (+/-0.05 mm).  Does this mean a variance of 0.05 mm in the diameter throughout the filament?  Or that the diameter is uniform, and it's within 0.05 mm of the advertised diameter?  
> **username_3**: It could mean either, but most likely the first option. Your print head is likely tuned to accept a certain (small) range of filament diameters.  
> **username_4**: @username_0 - it means the first of the two (variance throughout the filament).  That number does not give you a degree of _certainty_ but a degree of _uncertainty_.  The cases where the filament may be constantly +0.05 mm or -0.05 mm from its nominal value are just "special cases" of the more general one.  

---

### Answer by username_1 on 2018-07-11. Score: 3

Put it simply: they say 1.75 mm with a ± error of 0.05 mm. Which means your flow may vary ±2.9 % while you are printing creating blobs and such.

The smaller the filament tolerance, the more expensive the production costs.

> **Comments:**
> **username_2**: I'm curious how you arrived at 2.9% when I calculate +-5.7%.  The difference in surface area between maximum and minimum allowable diameter is 2.54 - 2.27 = 0.27mm^2.   Which is 11.4% maximum variance in extrusion volume or ~+-5.7% from nominal.  Have I done something wrong?  This is why I buy +-0.03 or +-0.02 filament.  They have 6.9% & 4.6% max variance respectively.  If I've done something wrong I may be paying more for less benefit than I think.  

---

