Here is a picture I took at x4 magnification on my phone, 19.7mm diameter cylinder 60mm long with a 2x10 mm HSS tool bar
With a "straight" cylinder you will see they are almost touching everywhere
"Straight" : in quotes because I am not sure if they are 100% straight but good enough .
If there is a taper they will not touch at the BDC position of the piston
No need to be mirror like, just smooth
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With a "straight" cylinder you will see they are almost touching everywhere
"Straight" : in quotes because I am not sure if they are 100% straight but good enough .
If there is a taper they will not touch at the BDC position of the piston
No need to be mirror like, just smooth
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