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266494 Erik Levin 2018‑09‑10 Rainy day project
It is raining cats and dogs, so I ended up with the day free (off from job 1 and
was supposed to drive to Philly to pick up a large optical instrument, but not
happening with the weather, especially as it is too large to fit in any closed
truck I have access to, so it will go in the pickemup). Given the several
projects i could make progress on, I chose to start 9and complete) a new one.

I have had a Stanley No 3 sitting on the shelf for a little while (5 years?)
waiting for some love. It came with a broken tote, some cracks at the mouth,
twist to the body, and about 0.7mm deep groove along the entire sole (0.7mm deep
at axis of the sole than at the edges), as if it spent its life being used for
jointing sans-filled wood prior to falling into my lap. I have no before
pictures, as I wasn't planning on going where I did with it. I did strip it a
few years ago and run it through several rapid cycles to about 150C in my heat
treat oven as a minimal stress relief (more to see if the crack were going to
run easily).


First was the tote. Clean the break faces, with acetone moistened wipes,
carefuully drill matched holes in each part for a bamboo skewer dowel, and
epoxy. Cringe if you want, but the condition did not warrant a 'perfect' repair.


After starting on the sole with 40 grit, I realized that it was going to take
more time than I was willing to give it, so I upped the game. Popped it in the
shaper (80 year old electron burner that makes flat surfaces) to take it down to
the point I could make decisions.


Other than the toe and heel, it cleaned up pretty well, but looked..... wrong.
So I figured, why not turn it up to 11?


I have a scraping job coming up-- metal scraping, whereby one uses manual labour
to take, for example, a 55mmX220mm cast iron surface from flat to really, really
flat (though not perfectly smooth). This is the process used for machine ways on
precision machines, lapping plates, and so on. So, out came the bluing and the
scraper. I do not have much technique. Scraping is a serious skill. I don't do
much so I will probably never be better than a competent beginner. I should take
a class, I can get the time and money.


The result: 
https://postimg.cc/image/smp85twon/
https://postimg.cc/image/bm6bx5z2v/
https://postimg.cc/image/s9xtzo1k7/

Other than the untouched areas at the toe and heel, it blued to a nice uniform
spotted surface (medium transparent haze of blue broken by the high spots). The
dark-looking spots on the sole are burnished points from the surface plate (they
may be as little as 2 or 3 microns high relative to the surrounding shallow area
on a well done surface, but probably trend more like 20 to 40 microns, here).
It need not be perfect, so I stopped here. No polish or abrasive was used after
scraping, other than a fine stone to knock off the burrs left by each stroke of
the scraper. The scratches that are visible in the photos are not in person
(other than the untouched toe and heel areas). It is actually flatter and
smoother than one of my (commercial, scraped, precision, with paperwork)
straightedges.


I still need to do the iron. It hasn't been touched yet. Time  for the scraping:
about 4 hours (roughly a dozen cycles from roughing out to chasing points) Total
time: about 6 hours.


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Recent Bios FAQ