Announcement

Collapse
No announcement yet.

Metal Cut Off Saw (drop saw) modification

Collapse
X
 
  • Filter
  • Time
  • Show
Clear All
new posts

  • Metal Cut Off Saw (drop saw) modification

    Most of us will have one of these; a 355mm grinder blade attached to a motor the use of which is to attempt to cut metal into lengths.
    They work ok for simple cuts but my finding is that they are hopeless at cutting angles. If one attempts to cut a 45deg angle the in-built vice does not hold well.

    Also the slot for the blade is too wide and there is not enough table support to the right of the blade.

    Anyways I determined to modify mine.



    First modelled it all in Alibre Design. These images are from the latest Beta version; nice they are.

    I have several "motor mount plates" and one of those became the source metal for the base.





    First I squared up the plate. Then set about the drill and tap; yes that is a lot of holes to drill and tap. The first pass at the holes was with a center drill and I allowed it to also create a slight taper for the 12mm holes. My mill does have a digital readout and that helped heaps. Best news at this time was that I did manage to get thru the exercise without making any mistakes.

  • #2
    I rather butchered the u-section that is the hinge during the removal process. It was (eventually discovered) to have been spot welded to the base; plus it looks like some previous owner had added a bit of arc weld to the edges.

    Anyways the face needed a cleanup prior to assembly. It was a tricky piece to hold as is was not square such that it was not readily held in the vice. My solution was to use a couple of 30mm x 30mm blocks of wood. It dialed in ok with a few taps; then I ran the milling cutter thru it at 1250RPM a couple of times with my favourite 75mm Face Cutter.

    Finish was so nice I thought I would share it with you.


    Now we are into the assembly. Made sure the fence was nice and square to the table.



    Made sure the blade was nice and square to the fence. What you are looking at below is a ground steel block gently placed against the blade and a square from there to the fence. There was enough wiggle in the 3 x bolts that hold the hinge to make it very tidy and I was well pleased.

    Comment


    • #3
      By now I was very keen to give it a drive. It is a bit overkill but I wanted to get the best out of it so used some milling clamps to hold the work. The angle iron is resting against a couple of studs to set the 45deg angle desired.


      The observant of you will notice that the 8mm bolts holding the wheels on are poking thru the plate. I did think about trimming them in the lathe; but there are 16 required so I figured I would just put in a couple on each wheel for now and order in more of the correct length.

      A couple of cuts later and I had this. Were they 45deg; well yes they were. Even I was impressed.


      The finish was nice also. The whole unit must weigh near 30kgs and I figure that has helped the stability some.


      I noticed a while later the wee offcut that was cut from between the two lengths. Decided to see if it also was as square as it looked. What do you reckon?

      Comment


      • #4
        Here is the finished article.



        This link has a pdf of the drawing with all the holes.

        Comment


        • #5
          Looks like a nice job.
          Paul A.
          SE Texas

          Make it fit.
          You can't win and there is a penalty for trying!

          Comment


          • #6
            Nice job,and a definite improvement over the stamped steel nonsense from the OEM.

            Have you thought about making up a toggle clamp to fit the same hole pattern?

            A good sized one of these might be the trick-
            https://www.mcmaster.com/5128a58
            I just need one more tool,just one!

            Comment


            • #7
              Originally posted by wierdscience View Post
              Nice job,and a definite improvement over the stamped steel nonsense from the OEM.

              Have you thought about making up a toggle clamp to fit the same hole pattern?

              A good sized one of these might be the trick-
              https://www.mcmaster.com/5128a58
              I have a box of those someplace. Will try and find them. Should work ok if they can be readily moved around and adjusted on the fly to set the clamp pressure.

              I fabricated a frame yesterday. Found g-clamps worked best (quickest) if the length allowed it. Second was the milling clamp; they do work a treat and it only takes a few seconds once you've done it a few times.

              Comment

              Working...
              X