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Tool Grinder

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  • Tool Grinder

    Got this recently in exchange for some machine repair work.

    Did'nt realize it would turn out to be as much of a project as it is.
    As I got it, there was no water trays & no water cup, and the wheels are toast
    but the rest of it seemed to be there.

    Cant find a name or label anywhere on it.
    I searched all over to compare to look of the motor housing and other
    details to try to figure out the make to no avail.

    See the cast iron ends & how they terminate to large raised areas
    towards the center where the 1/4"-20 bolts connect the 3 piece
    motor housing together.

    Does anyone recognize that construction detail as a clue
    to the maker?

    This machine has NO aluminum, and NO metric fasteners, it has cast
    iron tables, trunions,and wheel back plate although the plate
    may be steel I'm not sure.

    Mike Green

  • #2
    Since there is no name plate or specs on it I have no way to know
    the motor RPM among other things.

    The bearings squeel so they need to be replaced.
    The bearing # is 99504 but again no makers
    mark on the bearings.

    Not quite sure how to remove the bearings as they sit deep
    in a recess.
    This stack of parts gets removed to be able to see the bearing
    on the left end.
    The right end is a little different, fewer parts and a sort of split
    spring washer/spacer.

    Someone obviously painted the machine even in places where
    they should'nt have, which I removed with a wire wheel.

    This is the casting that forms the wheel guard/trunion mount etc...
    you can see the two small wide stubby pins that the trunion rides
    in that were fully painted as were the surrounding flat surfaces.
    Mike Green


    • #3
      Your grinder has a lot of similarity to the HF grinder I have. You might take a look at these 5 videos of a rebuild of the HF grinder to see if yours can be further disassembled the same way:


      • #4
        Hi Gary,
        I've seen the videos and while they shed some light on HF machine,
        mine is a completely different beast, much heavier built.
        Thanks for the response though.
        Mike Green


        • #5
          It is a good chance that it is a Baldor as they are a major manufacturer of grinders and have been for years. Here is one of their pedestal grinders from the 40's with the same construction, which is typical for the period;

          It is probably 3600RPM, any good bearing house can match up the bearings for you.
          Jim H.


          • #6
            Thanks Jim,
            I think you've got it pegged!
            Mike Green


            • #7
              Originally posted by JCHannum View Post
              It is a good chance that it is a Baldor as they are a major manufacturer of grinders and have been for years. Here is one of their pedestal grinders from the 40's with the same construction, which is typical for the period
              Baldor is also my call. Excellent grinders.


              • #8
                Possible match for your bearing here:


                Look about a third of the way down the page, in the "ND" column. It cross references to 6204-2RS, a pretty garden variety motor bearing. That page gives dimensions, see how they match up with what you have.
                Looks like a fun project.


                • #9
                  Hi Alan,
                  Thanks for the link.

                  I see your in Dracut, I'm in Lowell which as you know is just one
                  town away.
                  I was born in Dracut in 1960 and lived there for my first nine years and
                  then the family moved to Lowell. I've been stuck here ever since.

                  Perhaps we could get together sometime for a shop visit.
                  Mike Green


                  • #10
                    Was busy with other things, but now back to this project.
                    Got the bearings at the local eastern bearing in Billerica Ma.

                    Made 4 shouldered bushings with counter sunk holes in the large end
                    to receive the rounded off ends of threaded rod to act as pushers
                    so I could push off an end bell.

                    Mike Green


                    • #11
                      The bushings and threaded rods worked nice and the end bell came off easy.
                      A cheapo 3 jaw puller and a little light tapping with a hammer persuaded
                      the bearing & spacer to come off next.

                      The shot above shows the opposite end of the motor shaft.
                      Notice just past the inside of the bearing you can see a felt washer
                      and then the inner steel plate with 4 theaded holes.

                      The next shot shows a stack of 7 parts.
                      right to left...inner steel plate W/threaded holes....felt washer.....
                      ....bearing....spring washer(large end against bearing outer race so that it wont spin).....
                      ....thin( 0.031")spacer washer with depressed center section to house felt washer.......
                      ....felt washer....and outer steel plate w/through holes for the round head machine screws.

                      Now notice that there is NO thin inner spacer w/depressed center to house
                      the inner felt.
                      It seems as though upon assembly, that the felt would just squish as the screws are drawn
                      up tight pulling the inner steel plate against it.

                      This shot shows the mock up of the stack next to its relative position
                      along the shaft.
                      Mike Green


                      • #12
                        oops forgot the pic of the 7 parts.
                        Mike Green


                        • #13
                          It just seems like there should be one of those depressed washers
                          at the inner end.
                          Anyone agree or disagree??

                          I would like to get this figured out before I press the bearings on!

                          Also after having removed the bearings and the spacer/sleeves, I decided
                          to mount the shaft between centers to check runout at the shoulder
                          face where the inner bearing race /face seats against.

                          I found about 0.001" axial runout using a 0.0005" indicator on one end and
                          somewhat less on the other end.
                          I thought that this would multiply alot by the time it got out to
                          the 6" steel plates.
                          So I honed a HSS tool and turned just a smidge off the shoulders
                          and got the runout to a couple tenths.
                          Mike Green


                          • #14
                            I called Baldor. I introduced myself, and began to explain that I have one of their
                            old 6" tool grinders and I am looking for.....woman interupts...
                            ...where are you calling from sir?...says the woman on the other end of the phone.
                            Lowell Ma. I responded.......silence.......then I get transfered to someone in
                            my state.....another woman says hello...

                            So I start all over again and explain that I'm lookin for info on the grinder
                            as the name plate is not on the motor...
                            ....Baldor...part number please...
                   dont seem to understand...I dont have the name plate or model
                            number, so I am trying to get that info from you...
                            Baldor...model mumber please....

                            Do you have a parts dept that I could talk to?
                            Maybe some old timer that would be familiar with baldor tool grinders?
                            I was hoping that a major long standing AMERICAN company like baldor
                            would be able to help me out.
                            You know good old customer service.

                            I'm looking for a parts manual and possibly parts for my machine.
                            ....Baldor.... spec number please....we handle everything from
                            here...model or spec number please...........................

                            So as you can see Baldor was no help at all, didn't even want to try.
                            What a drag.
                            So down cellar to the home shop I go.

                            I decide to see if I could make one of those depressed cup washers.
                            Measured the thickness of the original at 0.032"
                            Scrounging around, I found a piece of 0.032" stainless that I canabalized
                            from a junk wood planer platen.

                            Used a pair of aviation snips to hack off a chunk larger than needed,
                            and hammered flat.
                            Then cut close to a traced O.D. layout line using my die filer with a hack saw
                            blade mounted to get a workable blank disk.

                            Loaded the blank in the 4 jaw in the lathe to drill & bore to 1.120"

                            lop off a 1 5/8" length of 3" solid round 6061 alum at the horizontal band saw

                            Load the 6061 in the 4 jaw & turn these features

                            To match the original part shape so I can use it as a male press die,..which by the way is something that Iv'e never done before...use or make press dies that is....

                            More next post
                            Mike Green


                            • #15
                              Then of coarse I need to make the female die

                              The two dies and the bored blank ready to press

                              I used my cheap cummmins hydraulic 10 ton press to press the part between the two dies
                              & forgot to take a pic of that sorry.

                              Here is what I ended up with.

                              Not too bad I think.
                              Now just need to drill the 4 screw holes.
                              Mike Green