A couple of ideas for right corners with 20x20 extrusions

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Some aluminium extrusions are quite convenient for building various types of structures. Manufacturers usually have a lot of choices when it comes to making unions. However, you not always have the time to wait for a part to be shipped to make a connection. Other times it can be done more cheaply and easily if you can use a drill.

For certain 20x20 profiles, I have used an M6 screw to make right angle joints. The inside hole of the extrusion needs to be tapped and an additional hole will help for tightening the screw with an allen tool:



Other times the profile is so tight that no screw can fit in the inside channel, so then this other approach can be used:



My original CAD had the screws with a distinct color but that was lost in translation :-(

If you clic on the images below you can have a look at the same model in Autodesk A360 Image viewer (unfortunately it only works for a month).



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