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  • #583569
    petro1head
    Participant
      @petro1head

      I have a Clarke 6" band sawthat I use for cutting metal

      Last night the blade James and burned the motor out

      So I need a new motor however I would like to prevent this happening g again.

      Any suggestion what I could do?

      And before you say it, yes don't leave it running on its own

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      #28558
      petro1head
      Participant
        @petro1head
        #583591
        noel shelley
        Participant
          @noelshelley55608

          You need a Direct Online Starter, rated to suit the full load amps as stated on the data plate ! Good ones are not cheap. On getting one it has to be set to the current rating for the motor. Fla = 2.8A You need a 2-4A unit set to 2.8A. A fuse WILL NOT help in this application. If buying secondhand check that the coil voltage is 240V not 415V. Good Luck Noel.

          #583636
          petro1head
          Participant
            @petro1head

            I have just had a quote for a replacement motor from Clarke £200!!!!

            This seems rediculously high

            #583638
            Mike Poole
            Participant
              @mikepoole82104

              Motors do broadly follow various standards, the motor plate will often have the frame size as one of the parameters and this will define the mountings and shaft size and height. TEC have built a reputation for decent quality and a reasonable price, WEG are also a contender for an attractive price and quality. Google will find suppliers of both.

              Mike

              #583640
              Adrian R2
              Participant
                @adrianr2

                Machine Mart sell Clarke motors – which one do you need?

                https://www.machinemart.co.uk/categories/?search=motor

                #583641
                petro1head
                Participant
                  @petro1head

                  Not much info on the motor plate

                  s-l1600.jpg

                  #583644
                  Adrian R2
                  Participant
                    @adrianr2

                    The summary for the 3/4HP (550W) 2 pole from MM says frame size 71 and 14mm shaft.

                    Spec sheet here to check against yours:
                    https://www.machinemart.co.uk/AspSiteAssets/download_files/ClarkeElectricMotors.pdf

                    Here endeth my knowledge on the subject!

                    #583646
                    petro1head
                    Participant
                      @petro1head

                      Cheers

                      However the shaft dia is 16mm

                      #583654
                      Mike Poole
                      Participant
                        @mikepoole82104

                        A 16mm shaft is a bit of an odd size, shafts are often 11mm,14mm then 19mm, double check that the shaft is not 5/8” which is 15.875mm. As the frame size is not on the plate then it would be useful to measure the bolt centres for the feet and the height of the shaft Centre from the foot mounting surface. There are plenty of drawings of motor dimensions to be found online and you may be looking at a motor around £100

                        Mike

                        #583657
                        noel shelley
                        Participant
                          @noelshelley55608

                          Before you get to shaft size check the motor speed 1450 rpm or 2850 ! The first is a 4 pole motor the second is a 2 pole ! I could not read the RPM on the data plate, nor the current. Why not look for a second hand unit ? an adaptor could easily be made if the mountings are different. If you buy a new motor the guarentee will be void if you do not use a DOL starter or some form of over current protection. Be warrned ! Noel.

                          #583658
                          petro1head
                          Participant
                            @petro1head

                            Motor speed is 1450 shaft size 15.9mm

                            #583660
                            john fletcher 1
                            Participant
                              @johnfletcher1

                              I have an "Alpine" saw to which I fitted with a DOL starter maybe 30/35 years ago and it appears to be a similar machine under a different name. I have just checked my saw and the motor is 4 pole capacitor start 1425 rpm half HP.. So, I think almost any !/2 HP cap start motor can be fitted, maybe a bit of work is required with mounting bolt holes and shaft diameter. I would look out for a second hand motor for £20 or £30 and fit a DOL. Before buying second hand, run the motor and check the direction of rotation, most are easily altered but some not. John

                              #583663
                              J Hancock
                              Participant
                                @jhancock95746

                                I would go for at least a 1hp motor , better that the belt slips than risk another burn out.

                                #583664
                                petro1head
                                Participant
                                  @petro1head

                                  The motor is 1hp

                                  #583673
                                  Samsaranda
                                  Participant
                                    @samsaranda

                                    The motor in the photo is labelled as 500 watts, that equates to .75 hp not 1 hp. Dave W

                                    #583674
                                    noel shelley
                                    Participant
                                      @noelshelley55608

                                      Confusion between Ph 1 and Hp ? Noel.

                                      #583678
                                      petro1head
                                      Participant
                                        @petro1head
                                        Posted by Samsaranda on 02/02/2022 19:53:15:

                                        The motor in the photo is labelled as 500 watts, that equates to .75 hp not 1 hp. Dave W

                                        What equation did you use?

                                        #583680
                                        Pete Rimmer
                                        Participant
                                          @peterimmer30576

                                          HP = KW x 1.341 so a 500w motor is equivalent to about 0.67hp

                                          #583720
                                          petro1head
                                          Participant
                                            @petro1head

                                            I think the confusion is its says pH 1. which is phase not hp. my pal has the same saw and his is 350w

                                            #583726
                                            not done it yet
                                            Participant
                                              @notdoneityet

                                              I expect this is likely an imperial motor. Actually 15.87mm? 5/8”?

                                              How mm might spec their motors is debatable  and possibly misleading. That 500W may be gross consumption, not real horse power delivered. That may make it only 1/2HP (or even less!).

                                              Ignore the temptation to fit a more powerful motor.  That is not a sensible option.  Something else would break or the motor would still burn out if/when a jam occurs.  Running improperly tensioned belts is just plain ridiculous.

                                              Fitting an overload cut-out is the way to go.  A fuse that would blow with a stall would likely blow when starting the motor.

                                              Follow the sensible suggestions, particularly that of the proper electricians.

                                              The post by Noel was all that you required.  Follow that advice.

                                              Edited By not done it yet on 03/02/2022 11:53:00

                                              #583734
                                              SillyOldDuffer
                                              Moderator
                                                @sillyoldduffer
                                                Posted by not done it yet on 03/02/2022 11:43:50:

                                                How mm might spec their motors is debatable and possibly misleading. That 500W may be gross consumption, not real horse power delivered. That may make it only 1/2HP (or even less!).

                                                Ignore the temptation to fit a more powerful motor. …

                                                The motor plate says it's rated 240V and 2.5A which must be the input, about 660W. Therefore 500W is most likely the power output, and 76% efficiency is reasonable for this type of motor.

                                                500W is ⅔HP, not that anyone has any idea how long it takes a horse to cut a given quantity of wood!

                                                I agree it's generally inadvisable to fit machines with much bigger motors. Many negative effects keen bodgers might not notice, such as rapid wear. We rarely know what parameters a machine's designer worked to, but to keep costs down it's likely the frame is sized to match the motor. A big motor could flex the frame enough for a saw to cut inaccurately…

                                                Dave

                                                #583752
                                                not done it yet
                                                Participant
                                                  @notdoneityet
                                                  Posted by SillyOldDuffer on 03/02/2022 12:50:17:

                                                  Posted by not done it yet on 03/02/2022 11:43:50:

                                                  How mm might spec their motors is debatable and possibly misleading. That 500W may be gross consumption, not real horse power delivered. That may make it only 1/2HP (or even less!).

                                                  Ignore the temptation to fit a more powerful motor. …

                                                  The motor plate says it's rated 240V and 2.5A which must be the input, about 660W. Therefore 500W is most likely the power output, and 76% efficiency is reasonable for this type of motor.

                                                  500W is ⅔HP, not that anyone has any idea how long it takes a horse to cut a given quantity of wood!

                                                  I agree it's generally inadvisable to fit machines with much bigger motors. Many negative effects keen bodgers might not notice, such as rapid wear. We rarely know what parameters a machine's designer worked to, but to keep costs down it's likely the frame is sized to match the motor. A big motor could flex the frame enough for a saw to cut inaccurately…

                                                  Dave

                                                   

                                                  I’m sure you will make of it what you wish, but here is the spec for that (presumably) same motor, when searching ‘goggle’ for “CBS 45 MD motor spec”. I’ll stick to my guess that mm is likely trying to bull excrement potential purchasers. To me 500W gross is about right for a 1/2HP motor. My 150mm bandsaw only touts a 1/2 HP motor and that works quite satisfactorily, IMO.  But please note, it is only a guess.🙂

                                                  Clarke CBS45MD (4½" x 6" Metal Cutting Bandsaw

                                                  A top selling general purpose metal cutting bandsaw which combines sound performance with excellent value for money. Justifies a place in any workshop involved in the cutting of bar, tube and profile.

                                                   

                                                  • Cutting capacity – 105mm (4" round, 100 x 150mm (4" x 6" flat at 90°
                                                  • Quick change horizontal or vertical operating positions with saw table included.
                                                  • 370W, 230v / 1ph motor with combined ON/OFF & safety No-Volt-Release switch.
                                                  • 3 cutting speeds 65/95/165 feet per minute with spring tension arm control & adjustable vice for cutting angles 90 degrees – 45 degrees
                                                  • Handle & twin wheels for workshop mobility
                                                  • WEIGHT 65KG

                                                  Edited By not done it yet on 03/02/2022 14:59:48

                                                  #583759
                                                  Howard Lewis
                                                  Participant
                                                    @howardlewis46836

                                                    Interesting!

                                                    I think that I tend to apply a little too much tension to belts, rather than too little.

                                                    When my generic 4 1/2" Bandsaw occasionally jams, the belt does slip.

                                                    But I avoid leaving any machine running and unattended; for obvious reasons.

                                                    When I tired to weigh the saw, the needle went right round the dial and hit the stop, indicating 114 lbs. (50 Kgs+ )

                                                    Now I know why I gave up lifting ( JUST ) the saw in and out of the shop. It now lives outside, under a cover made of curtainsider material, having been sprayed with oil after almost every use.

                                                    It is used dry, because of the fear that lubricating the blade, although it may help the cut, could cause slip relative to the driving wheel.

                                                    Howard

                                                    #583780
                                                    SillyOldDuffer
                                                    Moderator
                                                      @sillyoldduffer

                                                      Posted by Howard Lewis on 03/02/2022 15:55:42:

                                                      It is used dry, because of the fear that lubricating the blade, although it may help the cut, could cause slip relative to the driving wheel.

                                                      Howard

                                                      I lubricate the blade on my very similar saw, and the driving wheel has never slipped. Paraffin on Aluminium, neat cutting fluid on steel. No logic in this: I've been doing it all this time without thinking. Ignorance is bliss! Don't recall the very basic Manual saying anything about cutting fluids.

                                                      No visible label on the motor. From memory it's 400W, I assumed input. Cuts well enough, though the blade it came with didn't last long.

                                                      Dave

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