Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: A 3D Printed Toolbox for Opto-Mechanical Components   Nowadays is very common to find headlines in the media where it is stated
that 3D printing is a technology called to change our lives in the near future.
For many authors, we are living in times of a third industrial revolution.
Howerver, we are currently in a stage of development where the use of 3D
printing is advantageous over other manufacturing technologies only in rare
scenarios. Fortunately, scientific research is one of them. Here we present the
development of a set of opto-mechanical components that can be built easily
using a 3D printer based on Fused Filament Fabrication (FFF) and parts that can
be found on any hardware store. The components of the set presented here are
highly customizable, low-cost, require a short time to be fabricated and offer
a performance that compares favorably with respect to low-end commercial
alternatives.

13
The categories of this paper are: quant-ph
37
The categories of this paper are: supr-con
5
The categories of this paper are: gr-qc
30
The categories of this paper are: q-alg
34
The categories of this paper are: chem-ph
19
The categories of this paper are: eess
22
The categories of this paper are: chao-dyn
16
The categories of this paper are: stat
18
The categories of this paper are: econ
28
The categories of this paper are: alg-geom
15
The categories of this paper are: nucl-ex
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The categories of this paper are: dg-ga
27
The categories of this paper are: comp-gas
36
The categories of this paper are: cmp-lg
29
The categories of this paper are: funct-an
35
The categories of this paper are: mtrl-th