Thanks for the kind words Pete! Being able to get things flat, parallel, square etc to the highest standards of accuracy with simple hand tools in the home shop is a marvellous thing. That is what initially generated my interested in it. Currently working on long follow up piece "Reconditioning a lathe" which will show a gaggle of different styles of lathe being done.
I didn't watch the video (I'm with Sasquatch mostly on videos) but John says the tuber claims its not for function improvement. I'll disagree with the tuber, I could give a crap about tool decoration, its about performance. Of course, 1/10 of a thou is not needed for a wood plane, but you get a tenth (or however good your plate is) when you scrape. Its inherent to the process. You can't dial it back to 1/2 a thou because its a wood plane. The cool part is, grinder or no grinder, you can get anything, including awkward shapes like this very, very flat.
I have scraped a few hand planes and think it makes a difference. They are often not very flat and since we rely on the feel of them on the work to create flatness, It made sense to start with a flat plane and rubbing them on emery paper (which is not lapping btw) can't get them very flat. I thought of grinding them but the set up presents some challenges and the cast iron section is so thin I was concerned about movement from the heat. (even with flood the temperature where a molecule of wheel meets steel is very high)
Here's a Record "technical" I just did for use with a shooting board. imo there is no point in scraping the sides of a bench plane unless you are going use a shooting board....in which case, the side has to be square. I found after sampling a bunch at a used tool dealer the typical Stanley or Record plane is a long way from square (sole to side) whereas the Technical was quite good (not as much to scrape to get dead on). The hole in the side is for a handle.
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From the article so many years ago
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