Optimal Diamter Sizes?

Hello,

There is two kind of different filament sizes for 3D printing, there is 1.75/3mm±0.05mm sizes.

As far as I know the optimal sizes for
1.75mm is actually 1.75 ±0.05mm
3.0mm is actually 2.85mm ±0.05mm (not 3mm at all, I don't know why the standard is stated to be 3mm, anyone knows why?).

Now my question is, if I am going to extrude the best filament in terms of diameter size, what kind of mm should I extrude for respective diameter size, and why? Also state your machine name if possible.

We are having a project to control the quality of our filament, that is why I need gather some real data.

All answer is welcome.

The reason why 3.00mm is not 3.00mm is because of 2 reasons: 1) the extruder can only accept 3.00mm, nothing over. 2) since common manufacturer can only make +/- 0.1; few can make +/- 0.05mm. Given this case, it's better to lower the nominal diameter to 2.90 or lower, so the filament is able to feed into the extruder without jamming.

Botfeeder, thank you for your post. You help me solved why my filament was jamming. Just checked the diameter and it was over 3.00 mm!

We did some testing with different 3D printers and my conclusion leads to:
1.75mm is actually 1.75 ±0.05mm is the optimal size for 3d printing, with 1.70 being a realistic goal to reach
3.0mm is actually 2.85mm ±0.05mm is the optimal size and I refer to Bootfeeders answer.

The mystery is solved and we now know how to proceed.
We will soon launch our own enhanced ABS and PLA filament branded as "3Dfilamenta", but still got some more testing to do before going live. Hopefully our product will remove most problems with current ABS and PLA or at least minimize the problem we have today.

There's a reason why it only use 1 significant value when they call 3mm filament. Nominal is 2.85....
Any company who didn't do their job properly tends to shoot for a 3.00, as a results they dont sell as well as 1.75, especially problematic in the Europe with the Ultimaker and similar printer using 2.85.

Yet, even 2.85 can jam your print. Depending on the mechanism of your feeding. If you squish too much your filament in order to push, you will flatten on one side and expand on the other side, which will cause problem. The ultimaker rev1 was a complete mess for its notorious extruding mechanism.

Although the problem with 1.75 mm is far less common, it is not surprising to see it happens either.