Petr-
I watched a video a few years ago of the scraping process, to restore the way on some sort of machine.
At first it seemed counterintuitive to start gouging into the surface, seemly randomly, but as the video progressed, with the bluing process to repeatedly check progress, it became apparent what was happening, and why.
Seems like a mix between science and art in some respects.
I guess my question is how do you start the process?
ie: what datum points do you acquire before you start, and how do you keep track of the progress from the datum points?
Seems like you could scrape off into a tangent direction, and no longer be parallel with what you want to be parallel with, even though the surfaces would mate as intended.
My city had an extensive electric trolley system in the early/mid 1900's, and it was all removed and scrapped in the 1950's.
Then in the 1980's, it was determined that it would be cool to put that trolley system back in place, and so many millions of our tax dollars were spent doing that.
The trolleys we have were purchased from South America, and renovated to some unknown extent.
Then we had two trolleys burn to the ground in one week.
They hired a consulting firm, and that firm discovered that many/most of the trolley maintenance proceedures were undocumented, and sometimes only a single individual could perform certain tasks.
The firm documented all proceedures, and set up a maintenance schedule.
No more burndowns, so far.
I highly value anyone who retains our technological skills.
It is critical for a functional society that we have that knowledge base.
Good to have you here.
Pat J
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