Hendrik-Jan is a student who just started his bachelor studies in electronics September 2019. He made us a pancake machine. For his frame he used MakerBeamXL beams with MakerBeam brackets.
The MakerBeamXL beams are 15x15mm in diameter and available in different lengths (max. 2000mm). MakerBeam aluminium profiles measure 10x10mm in diameter. These beams also are available in different lenghts (max. 1500mm).
In the pictures you can see that the smaller MakerBeam brackets are not covering the MakerBeamXL beams entirely.
Hendrik-Jan also created brackets of his own. The design of these 3D printed tube holders can be found here: https://www.thingiverse.com/thing:3885119. The created brackets were used to guide the tubes.