In Reply to: Re: Used Lift Clyinder posted by Tim Daley(MI) on March 19, 2019 at 05:14:29:
"The cylinder blueprint bore finish spec is 80 Ám"
Yikes!! You sure about that? Aside from the fact that is a metric specification it's a rather rough finish.
I don't have a factory surface finish for the NAA cylinder in my notes but the surface finish for the piston o-ring groove was specified as 100Ra. No units specified but given place, time, application, and magnitude I would assume units to be in uin, e.g. equivalent to Ra = 2.54um.
Modern practice for reciprocating hydraulic cylinder bores is a surface finish of Ra = 4-20uin (.1-.4um).