As mentioned earlier, not really necessary to scrape, at least not for accuracy/alignment, since this part was duly taken care of by means of grinding. However, because some beds got a little scratched, and because I was told it might be OK to just give the beds a light scrape to "break up the surface", I so did.
This is a "redo" on the topic on simple hand scraping.. machine scraping would have been the same, but since 95% of the work has been done (grinding), i tried to practice some hand-scraping.
We have learnt to scrape individual marks and lines, measure depth of the scraping and also to hinge part while "measuring"
These steps are shown again. Since I only "finish scraped", I didn't change blade nor stroke length..
Actually, admittedly I am a slow learner, but have finally taken the advice from the mentor, namely to use the body push style scraper and technique. This is so much more comfortable, easier on the arms, you have much control on each stroke as you use both hands to steer and push down. It aslo is easier to practise the "tap, tap" dance, ie. lift out after every stroke, thereby leaving no burr
I also show measurements/readings with a machinist level on the Myford bed as well as the difference between a scraped surface and a ground. .at least how it appears in my case