Scraping my Shars 4" Milling Vise

OK Got a good chunk more progress done last friday.

Below is a progression of rouging in the moving vise jaw and finishing. I did not go to the same level of finishing as the bedways as It is my understanding that this is not needed for semi-static scraped surfaces.

The milled surface is broken up (blind scraping) for better blue transfer
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Initial contact is quite poor
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After a few more roughing passes I have contact down the length of the slides
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The right slide is showing much better area contact than the left, thus I scraped the high areas on the left.
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Using the bedways to print the moving jaw
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Getting better all-over contact
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Lighter blue is helping make more educated decisions about where to scrape
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Very light bluing near the end of highpointing
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And this is where I called it done.
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And a beauty shot of the scraped bed and moving jaw.
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What I've learned since day 5:
  • You can rough pretty judiciously at first, I think I am too easy on it still and take a long time to get through the roughing
  • Determining flatness on parts with protrusions above the planar surface is tricky, hinge test cannot be used
  • The hydrodynamic bearing generated between two scraped surfaces is incredible, I totally get why we do this!
  • Printing a part using another scraped part as a template feels a lot different than rubbing on a granite plate. The blue acts like grease if used in anything but the thinnest layers and smears a LOT compared to the granite. Also it seems to develop less obvious burnished spots which is annoying when trying to highpoint.
 
Also I bought a tube of Charbonnel Etching Ink - Concentrated Blue. I bought it since some had touted the benefits of being water washable. Unfortunately I did not buy the version labeled as "AQUA WASH" and it is definitely not water soluble.

In general I like the Charbonnel as an alternative to Dykem Hi Spot blue. It feels quite a bit like the Hi Spot blue (much more so than the Canode). The color density is excellent. It does have a few notable differences. First, it is more "tacky" where the Dykem is more "greasy". It is a bit harder to develop into a thin film but once it is, it seems to hold up much better to repeated printings than the Dykem. Once a thin layer has been developed, it seems to smear less than the Dykem for metal to metal printing (have not yet tried the surface plate).

It does not clean up as easily as the Dykem using a dry paper towel (more sticky) nor is it tremendously soluble in Isopropyl Alcohol (IPA) which I use generously to clean the Dykem. Interestingly, a small amount of Charbonnel thinned in IPA leaves a super matte film on the surface. I might pick up some yellow ink and thin with IPA to use as contrast.

The Charbonnel (non-AQUA WASH) cleans up super easy with WD-40, and that can be cleaned with IPA. One extra step.

The Charbonnel is also about half the price of the Dkyem Hi spot (per oz)
 
macardoso said:
Also I bought a tube of Charbonnel Etching Ink - Concentrated Blue. I bought it since some had touted the benefits of being water washable. Unfortunately I did not buy the version labeled as "AQUA WASH" and it is definitely not water soluble.

In general I like the Charbonnel as an alternative to Dykem Hi Spot blue. It feels quite a bit like the Hi Spot blue (much more so than the Canode). The color density is excellent. It does have a few notable differences. First, it is more "tacky" where the Dykem is more "greasy". It is a bit harder to develop into a thin film but once it is, it seems to hold up much better to repeated printings than the Dykem. Once a thin layer has been developed, it seems to smear less than the Dykem for metal to metal printing (have not yet tried the surface plate).

It does not clean up as easily as the Dykem using a dry paper towel (more sticky) nor is it tremendously soluble in Isopropyl Alcohol (IPA) which I use generously to clean the Dykem. Interestingly, a small amount of Charbonnel thinned in IPA leaves a super matte film on the surface. I might pick up some yellow ink and thin with IPA to use as contrast.

The Charbonnel (non-AQUA WASH) cleans up super easy with WD-40, and that can be cleaned with IPA. One extra step.

The Charbonnel is also about half the price of the Dkyem Hi spot (per oz)
Click to expand...
I remember how difficult it was to get the blue thin enough. Richard had us add a bit of windex to thin it as I recall.
I bought the water soluble in blue.

Restricted Access 2023

www.dickblick.com
 
So all I have left on this vise is to scrape the bottom to be flat and parallel to the bed.

After the roughing that I had done prior to the bed, the surface seems to be within 0.0002" of parallel over the whole length of the vise. This should be moderately easy to correct. Again for the bottom of the vise I do not feel the need to get the same points per inch as I did on the bedways.

I plan to stop here, but there are more parts of the vise that could use attention. In particular:
  • The fixed jaw, scraping for good contact on the mating surface, flatness on the jaw mounting face, jaw mounting face orthogonality to the bed surface, and top parallelism to the bed ways.
  • The moving jaw, scraping the top for parallelism to the bedways and jaw mounting face for orthogonality to the bed ways.
  • The vise body, scraping the sides for flatness, squareness to bedways, and squareness to the fixed jaw. Scraping the internal moving jaw guide rails for flatness and parallelism.
  • Reworking the moving jaw bosses. I notice in some areas they are a loose fit to the vise body guide rails and tight in other areas. Reworking the guide rails will leave them even looser. This can cause the moving jaw to yaw sideways when a part is clamped off center. The cast bosses could be machined away and a bronze guide boss could be added, machined, scraped, or ground to a snug fit between the guide rails
  • Adding ball oilers recessed in the top surface of the moving jaw to feed oil to the moving jaw. Alternatively, I can be better about occasionally lifting the moving jaw to add oil to the ways and slides.
I don't feel these items are immediately necessary as this vise will be quite accurate for my needs upon the conclusion of the scraping of the bottom surface.
 
Janderso said:
I remember how difficult it was to get the blue thin enough. Richard had us add a bit of windex to thin it as I recall.
I bought the water soluble in blue.

Restricted Access 2023

www.dickblick.com
Click to expand...

Thanks for the link! I personally like the thickness of the concentrated ink. It is some work to develop the thin film, but once it is there, it stays put. I feel like I'm constantly adding more Dykem to keep the same blue thickness on my plate. Just my thoughts after a few hours of trying it out.
 
Excellent write up. And I am realizing that a Kurt vise is a much better value than I thought. :)
 
Wow. You really jumped in with both feet on this one. I probably would have found somebody with a surface grinder to rescue it, but you've clearly learned a lot from the experience (and shared it). Thanks for the writeup!
 
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