What kind of square for scraping?

Sblack

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I have a bunch of scraping tools now. Some straight edges, a biax power scraper, large surface plate. What I don't have is a way to measure perpendicularity. I have seen the granite squares, the cylindrical squares, box squares and of course the ground machinist squares. For the money, which would be the way to go? are the import granite 10x6" squares any good? Are the cylindrical squares practical for measuring squareness on a machine, like a cross slide vs bedways on a lathe? I have only seen those used on surface plates. Can you really count on a good old machinist square, like a starrett?

I am sure the first question you would ask is what do I plan to do with it but I don't have specific plans at this point. I have several machines that need some TLC. Any advice appreciated.
 
Granite and cylindrical squares are usually used on surface plates. They are used to calibrate a indicator for checking perpendicularity to a surface plate. A granite square could be used for machine alignment. A box square is used to fixture a part on a surface grinder to get your part square. I personally would use a quality knife edge square for machine alignment.
 
Do you have some piece of cast iron to use as your right angle reference hence forth? Something like a frame level or a wide cast iron square?
When Busch liquidated, some of there castings ended up in Perth Ontario, near Ottawa. Contact jrwood and arrange a pick up from Cardon tool. I got a surface plate from them that way. The drive was cheaper than shipping. You could also get a 16x8 square from core print in Hamilton ON.

Its fortunate that we are both in the same city as I can lend you a reference piece or two.

https://www.ebay.ca/usr/jrwoodca?_trksid=p2047675.l2559
 
Do you have some piece of cast iron to use as your right angle reference hence forth? Something like a frame level or a wide cast iron square?
When Busch liquidated, some of there castings ended up in Perth Ontario, near Ottawa. Contact jrwood and arrange a pick up from Cardon tool. I got a surface plate from them that way. The drive was cheaper than shipping. You could also get a 16x8 square from core print in Hamilton ON.

Its fortunate that we are both in the same city as I can lend you a reference piece or two.

https://www.ebay.ca/usr/jrwoodca?_trksid=p2047675.l2559

Do you have some piece of cast iron to use as your right angle reference hence forth? Something like a frame level or a wide cast iron square?
When Busch liquidated, some of there castings ended up in Perth Ontario, near Ottawa. Contact jrwood and arrange a pick up from Cardon tool. I got a surface plate from them that way. The drive was cheaper than shipping. You could also get a 16x8 square from core print in Hamilton ON.

Its fortunate that we are both in the same city as I can lend you a reference piece or two.

https://www.ebay.ca/usr/jrwoodca?_trksid=p2047675.l2559


hi Alexander,

in fact I have an unmachiined cast iron square. I bought it martinmodel.com If I could borrow a reference that would be great. I know of that place in Perth. My patents live in Stittsville which is half way there. I have been meaning to go visit although I am afraid of coming out broke! I will msg you off line. Thank you.
 
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I use a granite square I bought on Ebay for $200.00, To check lathe cross slides and sweep it's face with a round faced height gage to check squares, I also have a Mag Cylindrical square to test angle blocks. A good quality and brand name steel blade square works good to test lathe / cross-slide squareness by using dowel pins against the dove tail or setting square on the bed sideways and indicating in both sides like Keith Rucker did using a granite square. look at minute 3:04 & 12: min You can use a blade square to do it too. sorry to some but Keith mentions my name mentioned...https://www.youtube.com/watch?v=DwouJ7xut1U Also Stefan G at minute 30 shows height gage sweeping a blade square
 

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HI Richard. By referring to the $200 granite square, are you referring to the "10 X 6 X 1" PRECISION GRANITE SQUARE" first result on ebay, or a used one time sail item? What kind of squareness did you get right out of the box?
In the first link is the details of a frame level I scraped, and it had a .006" error from perpendicular. My scraping and measuring skills have improved since 2015. I would think that a frame level would be a better starting project as the cast iron is more workable than granite should the come from china with similar tolerance.
Below I have some links to some projects of mine regarding square checking.
 
I bought a used square. The label of what brand was long gone, but it had a test certificate saying .00002" / 8" I had a friend test it on a CMM and the spec was right. Sblack figured it out. A student bought a Shars new granite square and he had it tested and it was off. So I am not recommending buying one of those. Many inspection tools on Ebay show brands and labels. I would stick with them,,, a Good brand name.
 
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