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How? I'm quite interested as I don't have access to anything remotely resembling a surface grinder. In this case it is also necessary to scrape to an exact thickness.
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Thick glass can substitute for granite
- Thread starter Syaminab
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it will not be easy, that's why i suggested an easier target to the writer of the question.
you would be measuring the whole process of making the 123 blocks
bring them to .001" flatness and parallel with the surface grinder, then measure and scrape to specifications.
there is no magic, just very diligent measurement and scraping.
scraping can remove the smallest amount of metal you can't with a SG
to expand,
by scraping one surface parallel to the surface plate, you can indicate the other side to see it's parallelism by direct measurement.
any high spots can be recorded and scraped to parallel with the surface plate.
you'll be scraping to the final dimensions.
if the process is repeated on all 6 sides, you'l have a parallel and square device
you would be measuring the whole process of making the 123 blocks
bring them to .001" flatness and parallel with the surface grinder, then measure and scrape to specifications.
there is no magic, just very diligent measurement and scraping.
scraping can remove the smallest amount of metal you can't with a SG
to expand,
by scraping one surface parallel to the surface plate, you can indicate the other side to see it's parallelism by direct measurement.
any high spots can be recorded and scraped to parallel with the surface plate.
you'll be scraping to the final dimensions.
if the process is repeated on all 6 sides, you'l have a parallel and square device
Last edited:
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I didn't mean to sound like it was impossible, Mike, just for a first project, to hit size, parallelism, and squareness is going to be quite the challenge. And without knowing what instruments are available to verify each phase in the process.......difficult may be a little bit understated.
Plus, comparing a grinder with scraping, I dunno. Scraping is at best a series of high spots. Granted, they can be very close together, but I don't think you could scrape to a 4µ finish, but you surely can grind one. And those high points are much, much closer than you can ever get hand scraping. And then there is lapping, beyond grinding. I know there is a lot of deserved respect for the art of scraping, but there is a reason there is so much more grinding and lapping in the modern world. For the sake of nostalgia, or originality, or even just because a person doesn't own or have access to grinding and lapping machinery, scraping is a very viable option. But I'll never be convinced it is equal to or superior to grinding.
Plus, comparing a grinder with scraping, I dunno. Scraping is at best a series of high spots. Granted, they can be very close together, but I don't think you could scrape to a 4µ finish, but you surely can grind one. And those high points are much, much closer than you can ever get hand scraping. And then there is lapping, beyond grinding. I know there is a lot of deserved respect for the art of scraping, but there is a reason there is so much more grinding and lapping in the modern world. For the sake of nostalgia, or originality, or even just because a person doesn't own or have access to grinding and lapping machinery, scraping is a very viable option. But I'll never be convinced it is equal to or superior to grinding.
Last edited:
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you can grind a 4u finish, granted- but not on your home machine- but you can scrape and verify to a tenth
most people don't have lapping stations and the ability to even grind or verify a 4u finish.
for a lot of people scraping is the best option, in due respect.
it's my belief that amazing things can be done by those willing to make the mistakes others may fear to make.
most people don't have lapping stations and the ability to even grind or verify a 4u finish.
for a lot of people scraping is the best option, in due respect.
it's my belief that amazing things can be done by those willing to make the mistakes others may fear to make.