- Joined
- Mar 26, 2018
- Messages
- 8,407
I remember we would place an indicator on one side and push each corner while working around with the indicator.
If it moves, you know what to do.
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scraping in a surface gauge feedback needed.
- Thread starter Braeden P
- Start date
If it moves, you know what to do.
- Joined
- Apr 8, 2021
- Messages
- 73
WD 40 works good,
- Joined
- Mar 26, 2018
- Messages
- 2,724
Braedon,
I'll offer some thoughts are someone who is just a neophyte in the subject (just hit my 50 hours mark).
1) You have some deep scoring from what I would guess is you rolling the blade until the corner digs in. Take a moment to round the corners of your blade so they won't scratch or cut, even if you try on a scrap piece.
2) You have no contact within 1/8" from any edge. I'm guessing you are rolling off your corners (I do!). It is hard, but try to approach the edges at 45 degrees and be careful to not allow your blade to roll sideways as you exit the cut and take a chunk off the edge.
3) It looks like you are using a piece of polished granite countertop as a surface plate. 2 comments. First, it might not be as flat as you want. Not bad to start but I'd keep an eye out for a small (maybe 9x12") surface plate. Second, the gloss finish on the granite likely poorly transfers blue in comparison to the matte finish of granite surface plates or the scraped surface of a cast iron plate or straight edge. Sort of how blue does not transfer to a ground surface very well. This could be complicating the clarity of your printing.
4) Your latest pictures show pretty good distribution of spots (even if they are a bit sparse).
5) Be very careful of making the bottom convex, probably easy to do on such a short part. You can tell by if the part hinges in the middle (as one of your comments implied). If it is convex, you will be rolling the part when bluing and getting a false reading of coverage. When working on my vise, I had a feeling I was getting convex but couldn't get the high points to prove it. Ended up taking a scraping pass only on the middle third and still kept getting contact on the ends. Two more passes in the middle only were taken until the middle stopped showing many high points. Only then was it no longer convex.
Good luck and keep practicing!
Mike
I'll offer some thoughts are someone who is just a neophyte in the subject (just hit my 50 hours mark).
1) You have some deep scoring from what I would guess is you rolling the blade until the corner digs in. Take a moment to round the corners of your blade so they won't scratch or cut, even if you try on a scrap piece.
2) You have no contact within 1/8" from any edge. I'm guessing you are rolling off your corners (I do!). It is hard, but try to approach the edges at 45 degrees and be careful to not allow your blade to roll sideways as you exit the cut and take a chunk off the edge.
3) It looks like you are using a piece of polished granite countertop as a surface plate. 2 comments. First, it might not be as flat as you want. Not bad to start but I'd keep an eye out for a small (maybe 9x12") surface plate. Second, the gloss finish on the granite likely poorly transfers blue in comparison to the matte finish of granite surface plates or the scraped surface of a cast iron plate or straight edge. Sort of how blue does not transfer to a ground surface very well. This could be complicating the clarity of your printing.
4) Your latest pictures show pretty good distribution of spots (even if they are a bit sparse).
5) Be very careful of making the bottom convex, probably easy to do on such a short part. You can tell by if the part hinges in the middle (as one of your comments implied). If it is convex, you will be rolling the part when bluing and getting a false reading of coverage. When working on my vise, I had a feeling I was getting convex but couldn't get the high points to prove it. Ended up taking a scraping pass only on the middle third and still kept getting contact on the ends. Two more passes in the middle only were taken until the middle stopped showing many high points. Only then was it no longer convex.
Good luck and keep practicing!
Mike