Steel Square 1903 (312p)

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ken572
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Steel Square 1903 (312p)

Post by ken572 »

(ALL) :D

Interesting Read.

A practical treatise on the Steel Square,and

its application to everyday use 1903 (312p)

https://archive.org/download/practicalt ... 01hodg.pdf

Ken. :)
One must remember.
The best learning experiences come
from working with the older Masters.
Ken.
EricM
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Re: Steel Square 1903 (312p)

Post by EricM »

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liveaboard
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Re: Steel Square 1903 (312p)

Post by liveaboard »

I noticed one of my construction squares wasn't quite square; upon checking, none of my squares were square.
I went to a wholesale shop that had a retail counter, he had a machinist square, heavy thing with ground surfaces. We went to the back and I used the good one to check a shelf full of moderately [NOT cheap though] priced builders + carpenters squares.
I found 1 or 2 that was good.
He told me he'd had the machinist square in stock for years and let me have it cheap.

I bought a Russian machinist square at a flea market;, it was unblemished and quite square. Treasure!
I keep the European one in a sealed box [they're rust prone].

For large format work, like squaring the ends of plywood sheets [not square from the factory] I sometimes make one on the jobsite with a tape measure and a little math.
pete
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Re: Steel Square 1903 (312p)

Post by pete »

A hell of a lot I didn't know about just how much those common steel squares are capable of in those two links. Oddly it isn't more common knowledge, but it's pretty easy to "accurize" to at least wood working levels of accuracy the standard steel squares sold today. As Liveaboard already mentioned, there's very few new squares made today that are all that accurate right out of the box. In fact I'd fully expect anything bought to be inaccurate unless you can pre-check them like he did. About the easiest and most common standard check method for carpenters steel squares is to use the factory cut edge on a piece of plywood, set one leg of the square against it, draw a fine pencil line down the plywood on the squares other leg, flip the square 180 degrees on the same plywood edge and draw a second line parallel and very close to the first. Any inaccuracy in the square will then be doubled as shown by those two lines. You can adjust the square in either direction that it's out by just using a center punch and hammer. If the square shows the lines tapering towards each other you center punch dots on the inside corner where the squares two legs meet. If the lines drift away from each other you center punch towards the outside of the squares corner. Your using the center punch to expand the metal and to force the squares legs either together or apart.

Expect this to take a bit of time since it's sort of trial and error for how many punch marks it takes and how hard to punch it. The first time I did it took almost 20 minutes and maybe 10-15 punch marks before I was satisfied. It's also easy to go to far and start chasing your tail. So it's faster and easier to creep up on your adjustments than try for it all at once. When you think the square is correctly adjusted then repeat that line test on the plywood again, but this time draw the second line on top of the first. If the square is then correct the drawn line will be the same width down it's full length. After you do this you'll start treating a carpenters steel square a lot more gently in use since dropping it even once will almost for sure require it to be readjusted. But the method does work well. It's still a bit neanderthal since it does leave those tell tale punch marks. So I doubt I'd do this with a precision machinist square. For those I think I'd check against a proper cylindrical square on a surface plate and gently stone it into being square or surface grind if that's available.
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