Building the pyramid frame without welding

[skywatcher]

Step 7:

Make a M5 thread into the 4 mm hole, so that a M5 screw (M5 x 32 (use M5 x 40 and cut it to 32 mm)) fits into it:

[skywatcher]

Side view (the screw should have a right angle to the cutted edges oft he tube, and be 15 mm away from the outer vertical edge):

[skywatcher]

Step 8:

Drill a 5 mm hole into the base frame at the diagonal, and 15 mm from the corner (measured on the diagonal).
If you use the same flat angles as i used, you can use the 4 mm hole which is already in the angle to center the drill. 

Now you can mount the side tube to the base with the M5 x 32 screw:

[skywatcher]

The connection is of course not as stable as a welded connection, but it is sufficient to easily support the weight of the side tube. 
When all tubes are mounted, the stability will be more than sufficient.   

Tomorrow i will make the connections at the top of the pyramid, this will be more easy than the connections to the base. 

[titof]

excellent idea...
but how to do with the top ?...