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Topical, But A Dumb Question

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  • Topical, But A Dumb Question

    In my 63 years, I've always had trouble making a straight cut with any type of hand held saw(rip, cross cut, hack).

    I either dreamed or once heard that reversing the blade on a hacksaw so the cut was made on the draw stroke has the potential of eliminating, to whatever degree, this problem.

    I've got to make a number of cuts on a piece of brass sheet that is 0.020". If the blade reversal has potential that is what I plan on doing. Of course I'll make my cuts in a manner that gives me some cleanup room to the final desired position, and I plan on using a 32 tooth blade.

    Does any of this sound reasonable?

    Thanks
    John B

  • #2
    It kinda does in theory due to pulling being "self aligning"

    but I don't believe it works this way in practice --- there are far more joints than just your wrist on the hacksaw blade - your shoulder elbow and even your body stance comes into play and this is not self aligning...

    There's another huge factor that you will be fighting --- Pushing the blade in the geometry it's designed for is "self engaging" another words your cutting pressure exertion is compounded --- not so with pulling - it's a leverage thing from where the power is coming from to where the works getting done, and pulling sucks...

    It's just practice --- build a deck or house add on with a high quality hand saw and you would not believe how good you can get with 2 by 4's,

    I can make a cut that is every bit as good as a skill saw.

    It's a constant focus with every stroke - the thing is - is if your start to mess up you have time to correct it unlike a skill saw...
    Last edited by A.K. Boomer; 06-09-2012, 11:01 AM.

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    • #3
      Wrong saw

      For .020 Brass you want to use a Jewelers saw and a V-block. The saw is held so the blade is vertical and cuts on the down stroke. The V-block supports the material.

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      • #4
        In my 62 years I don't think I have managed a straight saw cut by hand but with a Japanese pull saw I have come very close to it.

        With a Japaneses pull saw one thing that seems to make a difference is that you can hold the saw right at the end of the handle, stand back and pull while eyeing the alignment. Also you can't quite put all your weight behind the saw like when you are pushing so you tend to go more gently all the while eyeing your alignment.
        "Patriotism is the last refuge of a scoundrel"

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        • #5
          Either way your going to have to focus on every stroke --- so you might as well use the one that gives you the biggest bang for the power output and that is pushing...
          even if you want to keep the bites small as this will allow you to use far less muscle and concentrate on control...

          It really is simple --- you only have two things to follow - one is the scribed or markered line and the other is keeping the blade 90 degree's to the board or whatever, what will aid you in the latter is starting the cut diagonal to the piece -- this way you almost can't screw up because your scribed or markered line will help you with the 90 degree rule...

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          • #6
            Number one: Saw must be perfectly sharpened. This of course would be much easier to achieve with a 12 tpi wood saw than a 32 tpi hacksaw if not for the fact that you can buy new, high quality blades and forget about resharpening them.

            Number two: The wider the blade, the less it will be able to get out of alignment in the cut. A 1" wide blade from a power hacksaw will give much better results than a regular 1/2" wide blade designed for a hand hacksaw. If you can find something even wider, so much the better.

            Number 3: Practice. Even if you only do a few test pieces before the one you actually care about rather than taken 30 years to master it, you'll get better results than otherwise.
            "A machinist's (WHAP!) best friend (WHAP! WHAP!) is his hammer. (WHAP!)" - Fred Tanner, foreman, Lunenburg Foundry and Engineering machine shop, circa 1979

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            • #7
              Gentlemen, thanks for the feedback. In all honesty, I suspected the responses provided would be the case. So, I'll proceed as advised and leave some latitude for clean up with a file. Then again, the local trophy shop has a shear they use to cut these brass sheets and I probably could just get it cut to size for a few bucks.

              Regardless, thanks.
              John B

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              • #8
                I'd get that to on a shear if straight, jewelers saw a v board as mentioned if nature of cut prevents shearing. imo a cut with the jewelers saw will need some filing to the scribed lines to resembled something straight. If no shear is available, I'd still go with the jewelers saw and file, easier to control than a hacksaw

                if you need an example: http://bbs.homeshopmachinist.net/showthread.php?t=13891

                on cutting straight in general, ie woodworking, I'm far from an expert but lack of power tools (due to # of machine tools) means i cut and dimension wood by hand when i have to. This is what I found works. Draw your lines. Have a meeting with yourself and declare, self, this cut will remain perfectly square and along the lines if I only do one thing: move the blade unerringly in the same plane. Your muscles won't naturally do that but by going slowly and concentrating on bring the arm forward and back exactly in the same plane (as best you can) you'll improve. you need a good sharp saw and practice as well of course.

                Seems like a stupidly simple thing but consciously focusing on the motion being in the same plane is what took me out of the crooked saw club.

                Interested to here what the more experience straight cutters have to say on staight cutting tips and tricks
                Last edited by Mcgyver; 06-09-2012, 01:02 PM.
                .

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                • #9
                  A couple of other things come in to play here. From my experience....

                  If you wear glasses, they may gently distort your view, making a straight line seem crooked and vise-verse. Especially true if they correct for astigmatism.

                  Some of us can't really tell when we are at 90 degrees when cutting. 80, 85 and 90 degrees all look alike when I'm at the wrong end of a saw or drill. I find that I can do much better with a support block that is cut to the angle that I want to match. That gives me a visual cue when I'm off.

                  Dan
                  At the end of the project, there is a profound difference between spare parts and extra parts.

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                  • #10
                    All the Japanese saws cut on the pull stroke. Except for my Sandvic/Lenox hacksaws, I tossed my American/Brit saws 25 years ago and never looked back.

                    Because of the tension in pull, they have a narrower kerf and cut beautifully.

                    And... the finish saws are typically "mirror finish". This way you line up the reflection of the wood on the saw (run your eye though the far edge. saw and continue) and get a perfect right angle. This is a mystery to most American owners ; I learnt that while in Japan. You almost never see a square or a pencil.. so obvious when you see it..
                    Last edited by lakeside53; 06-09-2012, 01:31 PM.

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                    • #11
                      straight cuts

                      One thing that helps you make straight cute is to position your body so that your shoulder, elbow and hand are all in the plane of the cut you want. Then practice not wobble when sawing. Look at the blade, not the saw frame. The blade may not be well aligned in the frame. It would also be good to practice on some scrap.
                      Have fun!

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                      • #12
                        Another tip is to scribe two lines, one at the cut line and one about double the kerf width or so outside of that. Keep your cut between the two.
                        Jim H.

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                        • #13
                          Originally posted by jr45acp
                          the local trophy shop has a shear they use to cut these brass sheets and I probably could just get it cut to size for a few bucks
                          That's exactly what I was going to recommend. Actually a heavy duty paper cutter will handle .020" brass.

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                          • #14
                            Something that thin calls for shearing, not cutting with a hand saw. But in general, sawing straight by hand is something that takes a while and patience to learn. The thought about getting all the body parts lined up correctly is right on. It's like shooting pool, in a way.

                            Boomer, I'm sorry about the poor condition of your skil saw. I've been cutting with a hand saw for decades and have gotten pretty good at it, but I can't reproduce the look of a skil saw cut- at least one that' working properly anyway If you can do that- well my hat's off to you sir.

                            I like pull saws for various things, but they won't fully replace the normal hand saws. I like the fact that they are normally extremely sharp and have an easy cutting action, and that does help to make the cut smooth and straight. On a job site cutting 2x4s- personally I'll stick with the normal hand saw.
                            I seldom do anything within the scope of logical reason and calculated cost/benefit, etc- I'm following my passion-

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                            • #15
                              Crooked saw cuts--------------

                              I quit sawing wood about 63 years ago, when Uncle Hershall caught me in his wood shop, using his tools to saw a board. I was real proud of myself and thought he was too, as he stood there, watching.

                              Then he walked away, mentioning that "I sawed like a girl".

                              --G

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