A pantograph is a four bar linkage based on a parallelogram that scales the movement of a point by a set factor.
For the sake of simplicity, the design is non adjustable but I have included linkage files for scale factors (SF) of 2, 3, 4, and Pi.
After putting the design through some tests, I found the margin of error to be consistently under 1%.
Hardware
10x
M3 x 8mm*
What to print
2x Link_1
1x Link_2 (2x for SF of 2)
1x Link_3 (0x for SF of 2)
1x Base
1x Base_Pin
1x Base_Pin_Cap
1x Pin_1_Base
2x Pin_1
2x Pin_2
1x Pin_2_Short
3x Pin_1_Cap
3x Pin_2_Cap
1x Support
1x Pointer_1 (for joint closest to base)
1x Pointer_2
_*Affiliate Link_
Elliott_Turner
