Blast gate for 40mm pipe
Fully enclosed, so you can't break the gate by accident.
A little arrow points to the close-direction.

Print the cover plate 2x, and the other parts once.

Hardware needed :
 6 x  M3*12 Bolt
 6 x M3 Nut

 1 x M4 x12 Bolt
 1 x M4 Nut