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  • Small project completed today.

    I needed a bit of a break from my mill project and I also have several timing belt pulleys to make. I also need to slot a couple of internal keyways for the mill project. A while ago another board member posted a picture of a very nice tool to do such jobs on the lathe, basically a small hand operated shaper/key-slotter.

    When I saw that I knew it was exactly what I needed to make the parts I require. I have been scribing dials and slotting pulleys by cranking the carriage back and forth and that gets old fast when you have to do it a few thou deep per cut and 700 strokes just to make one pulley.

    So, a few weeks ago I decided to make myself such a tool. I stole the idea but not the design as I never copy or build from plans. I also wanted to use materials at hand. This is what I came up with:



    I decided to put some info on the bottom so after I croak and it turns up on E-bay someone will have a clue what it is for and what it fits. It goes on the cross slide in place of the compound using the same attachment method. As well, there is a 5/16" pin that winds in the provided tapped holes on the cross slide and locates the tool so it is automatically aligned exactly the same when attached to the lathe. The pin engages one of the holes seen on the bottom right. I put in two holes for two pins and then realized that unless an interference fit only one pin would ever actually be locating and holding.

    It is made from 1 1/2" welded square tube, .187" wall. This I chucked up centered in the 4 jaw to within a couple of tenths. I didn't feel like line boring the bushings so I wanted to see if I could get away without doing that. The ends of the tube were bored partially round inside to accept the two bronze bushings as a press fit. The bronze bushings are about 1 1/4" long each with shoulders.

    The shaft is mild steel, OD 1". It was turned down from 1.125" and a hole bored in the end to accept tool holders.



    When set up on the lathe for cutting pulleys or gears it looks like this:



    By bolting my lathe milling table to a riser block that is clamped to the ways I can also cut racks.




    The tool has a stroke stop that is an adjustable cam which has eight positions. Each position is 1/16" deeper than the last for a total adjustment of 1/2". The brass block to the right has a screw that can also be adjusted +- 1/16" to achieve any intermediate adjustment. That block is also very closely fitted to the slot milled in the top of the tube and acts to prevent the shaft from rotating.



    The cam was milled on my lathe along with all other milling operations on this project. Also in this picture is the tool holder which fits a 1/2" hole in the end of the main shaft and is held by two set screws that bear on the relieved area of the holder.



    On the top of the main tube is another brass block on the right which acts as a back stop. The back stop distance may be adjusted by simply placing whatever size block is required between the sliding block and the back stop.



    The handle gives a seven to one advantage and is slotted (not visible). The shaft is pinned to the handle with hardened drill rod through the slot in the handle and the handle pivots on another length of hardened rod in the base. The pins are retained with set screws.



    This little project was a blast. I had a lot of fun building this. I really like working to close tolerances and this gave me a chance to practice that. The shaft when extended has about .0002" slop and unmeasureable rotation as the slider guide block is lapped to fit the slot it rides in. Although it doesn't have many parts every part is a "high value" part in terms of time and operations required to make it. The top main assembly can be removed from the base that fits the cross slide with just two bolts. It has milled slots on the side so it can be toe clamped to a table.

    I tried it out and in aluminum it will easily take cuts .020" deep per stroke. I know this is going to be a very handy addition to my shop.


    [This message has been edited by Evan (edited 03-12-2006).]
    Free software for calculating bolt circles and similar: Click Here

  • #2
    Absolutely incredible! It looks like a tool that a person would pay a few hundred bucks for.

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    • #3
      nice job Evan, a very handy addition to the shop. from the view with square, it's substantial looking! how big is the bore and any comments on tricks and challenges in machining that long a cylinder and bore to those tolerances?
      .

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      • #4
        I was wondering why you hadn't post much over the weekend. It might be a little large for my present lathe, but I would build that from your plans, when you publish them (hint,hint).

        ------------------
        Today I will gladly share my experience and advice, for there no sweeter words than "I told you so."
        Today I will gladly share my experience and advice, for there no sweeter words than "I told you so."

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        • #5
          As usual a good idea brilliantly executed.......................................... .................................................. .......................................I hate you.


          ;-)

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          • #6
            UP to your usual high standard of work, I see. You made a comment that tickled me, about marking just what the gizmo is used for in case it winds up on ebay some day. I have a whole drawer full of widgets I've made over the years, to solve some problem at the time (mostly gun assembly related), with no clue today what they were used for. If the same dilemna were to come along again, would I recognize the tool for what it was intended? Or would I make another?? Ebay my ass. I need to mark them for my OWN future use. Your hand hobber is grade A, ya hoser.
            I'm here hoping to advancify my smartitude.

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            • #7
              Damn!!! NICE work!!

              I want one too....but there's only 1 small problem with the design.....and that's the form of power it requires. Built by "Armstrong and Co."?? Now, those guys went outta business long time ago...where's the motor and pitman arm to run that thing??

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              • #8
                Hi Evan,

                That looks nice. Why did you put the lever vertical instead of horizontal - ease of construction in locating the lever pivot?

                If the lever extended out in front of the lathe it seems like it would be easier to use.

                cheers,
                Michael

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                • #9
                  Beautiful!

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                  • #10
                    Real nice Evan, yep, really nice.. Good job with the cam by the way, that is my downfall, dealing with cams, kinda like chess, you gotta think ahead, weird thing is, I'm pretty good at chess...

                    Also, fine photography as usual. Hey, how bout throwin a monkey wrench in the deal. Next time, post some fuzzy, outta focus, under exposed, dark photos of your work Good show, JRouche
                    My old yahoo group. Bridgeport Mill Group

                    https://groups.yahoo.com/neo/groups/...port_mill/info

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                    • #11
                      To answer a few questions:

                      The shaft is 1" OD. Chucking up the square tube accurately to bore the ID isn't the same as chucking up a piece of round in the 4 jaw. First, the square stock wasn't precisely square, it was about 10 thou larger across one pair of sides than the other. This means in order to center the work measuring with the DTI opposite corners only to be equal reading and the other two corners (diagonal from each other) to be equal but at a different reading. The jaws must be adjusted as adjacent pairs opposite the other adjacent pair, not single opposite pairs.

                      I used large 1/2" blocks of aluminum between each jaw and the work, with the blocks sticking out about another inch past the jaws on the work. This ensured a very secure hold on the work when boring. I also have a good 6" Bison 4 jaw which helps.

                      Techshop,

                      There are no plans, what you see is the closest you get. Sorry.


                      Michael,

                      As for putting the lever horizontal that is just begging for me to back into it and ruin the work. I also figured it would produce the least flexing in the entire carriage (gibs tight!) by putting it vertical as the weight of the handle wouldn't be trying to rotate the assembly and I wouldn't be tending to push or pull it up or down.

                      I forgot to mention that it has 1 1/2" maximum stroke.
                      Free software for calculating bolt circles and similar: Click Here

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                      • #12
                        Excellent work, as usual... Evan.
                        THAT OLD GANG 'O MINE

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                        • #13
                          "where's the motor and pitman arm to run that thing?? "


                          Trust me KF, the idea has occurred to me...
                          Free software for calculating bolt circles and similar: Click Here

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                          • #14
                            Evan, I should just make a script that automatically says,"Nice work Evan" every time you make a post showing your latest project.
                            I know its a huge pain in the ass to do but it would be nice if you take step by step photos of one of your projectst to show your techniques. I know with all your posts as a whole, you have shown us most of your techniques, but it would be nice to see them applied in a nice how to project/article.

                            [This message has been edited by BillH (edited 03-12-2006).]

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                            • #15
                              I considered it but I would have to wash my hands too often. Maybe on the next project. On this one I was trying some new (to me) techniques which all happened to work really well. I guess I should have taken more pics.

                              Thanks for the compliments guys.
                              Free software for calculating bolt circles and similar: Click Here

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