Proper Way To 'clean Up' A Surface Gage...surface?

[francist]

That case hardening is in great shape. Lots of times the top gets pretty worn off (like mine) but yours is mighty nice looking.

-frank

 

[Bob Korves]

Haha, not sure if sarcasm... I have a $40 Windows phone, does everything I need - moderately well - including mediocre pictures...


View attachment 138415
Looks better in person, but again - my phone camera leaves a lot to be desired...



That's exactly what I'm afraid of - and why I didn't just 'dive in' and lap it. I feel like there are too many variables, and that Starrett + rust > Me & Grizzly + 1000 grit...

Unfortunately, I bought this used to go with my Alina No. 88 (.0005") and my Grizzly surface plate for checking out and scraping in my import mini lathe (Grizzly G0765 - which, incidentally, continues to shock me with just how horrific the quality is), so I don't have anything of higher quality to check it against.

I have access to a large quality surface plate and an Interapid .0001" at work, but the guys in the QC lab don't exactly take the best care of them, and I have nothing to clamp it in.

Trying to get set up with some basics of moderate-to-good-used quality tooling. Seems I always need something to check out the thing I'm using to check out other things...

I have the same Starrett surface gage, same vintage, same condition. Got if for free from a machinist buddy, with some rust on it, which came off nicely and left me a beautiful tool, with gorgeous color case hardening. I had to make and harden the scriber, which was missing. It is a very nice tool. When I got it, when I tapped down on the corners with a finger, I could hear and feel it rocking. That test requires no tooling beyond a surface plate and a finger. Just tap it down solidly with your finger on the edges and corners and pay attention. After finding it was not flat, I rubbed the bottom on my surface plate a bit to shine it up so I could see the high spots, then went to work with the scraper and marking dye. It was slow work because it is really hard and has been surface ground, and the scraper wants to just skate over it. But a carbide scraper, properly sharpened, some experimenting with different attack angles and tool pressure, and it was cutting -- slowly. It really did not take that long to make it flat, but it did require some effort. The free price energized me. There are still a few former rust pits that can be seen through the scraping, they are of no significance. I can always add a little sign that says "What are you looking here for?" as my mom would say.