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PM1236 initial start up?

Discussion in 'PRECISION-MATTHEWS' started by BFHammer, Jun 16, 2017.

  1. BFHammer

    BFHammer United States H-M Supporter - Premium Content H-M Supporter-Premium

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    Just got my new PM1236 set up.

    On my initial run I checked all the safety interlocks, plugged her up, had power. Switched the motor into FWD and got nothing. Rotated the chuck slightly selected a different speed still nothing. Tried motor in REVERSE and everything came to life. Was able to run at a variety of different speeds in REVERSE but switching to FWD was the same as switching the motor to OFF.

    I tried the carriage feed and the cross feed and they worked but in the opposite direction that they should have. I don't think this is normal just because the motor was in reverse. But with the carriage feed lever set for right to left it moved left to right.

    It was late and I was about to give it up for the evening and I shut it down and unplugged it. Pulled the electrical panel off just to see if I saw anything that looked out of the ordinary, which I didn't. Didn't touch or take a meter to anything and put the cover back on. Just to give it one more try I plugged it up and started her up again. Switched the motor into FWD and she took right off. When I tried the carriage feed/cross feed and lead screw everything worked and moved in the correct direction.

    So it appears all is well but wanted to see if this made sense to anyone. I'm certainly not an electrician but it seems that simply unplugging and plugging in again set everything straight - doesn't make sense to me. Anything else I should check?

    Thanks,
    Mark
     
  2. dieselshadow

    dieselshadow United States Do you smell something? H-M Supporter-Premium

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    Mark, have you called QMT yet? A quick phone call can get you running and answer all of your questions fast.
     
    darkzero likes this.
  3. mksj

    mksj Active User H-M Supporter-Premium

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    It sounds like a faulty forward motor control (spindle) switch which is operated by a cam at the end of the rod. Otherwise there could be a problem with the forward contactor KM1, which you should here click on when the machine is put into forward. There is also and indicator on the contactor to show its position. Over time the contactors can also get bad contacts because of arcing, so if the spindle direction switch is working and the contactor is closing, then most likely is a bad contact. This would also be more common with the contactor used most often, i.e. forward. You can also check AC voltages across the contactor coil and also the motor terminals, but you need to be very careful.
     
  4. BFHammer

    BFHammer United States H-M Supporter - Premium Content H-M Supporter-Premium

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    Actually I was hearing a click. When it was working in reverse and I stopped the motor and then tried to put it into forward I was hearing a click. I guess this would mean that the issue was more likely the spindle switch. Is it possible that the cam could have been out of position. This is a brand new machine so I haven't taken it apart yet but hesitant too until I knew what I might be looking for. Especially now that it seems to be working normally. I'll put some more run time on it tonight - anything I should be paying particular attention too?
     
  5. Tozguy

    Tozguy Active User H-M Supporter-Premium

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    My lathe is a 12x36 but not a PM brand. There are two switches side by side under the gear box that are operated by a cam at the end of the control rod as you already mentioned. On my new lathe the forward and reverse worked but did not have the same feel. It took more movement in one direction than in the other. In one direction it only worked at full travel of the lever. I tweaked the angle of the switches to get a more equal action in both directions. It is quite conceivable to me that if your switch only works sometimes and only at the end of the stroke on the lever then the switches need to be repositioned with respect to the cam.

    Otherwise I would follow the start up instructions of your lathe and hope for the best.
     
    Last edited: Jun 17, 2017
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