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    Default please, questions about lathe service

    hello please, i have a few questions :

    - how to verify torque for :
    ... a specific rpm on m-spindle, vdi turret ?
    ... s-spindle : specific rpm, m19, m147 and m110 ?

    - how would you align a dial indicator, so to have its palpator parallel to X axis, pointing towards the spindle center, on a lathe without Y axis ?

    - let's say that there was a crash : turret, spindle and tailstock, are all out of alignment : which is the 1st thing that you align, why, and how ?

    - let's say that there was (another) crash : only main spindle is out of alignment, and if you wish to turn a cylinder, you will obtain a cone :
    ... how do you rotate the spindle back, to be parallel to z axis, verifying without moving the turret after the spindle was rotated ? thus, after spindle rotation, you have to be sure that you will obtain a cylinder by cutting, even if you don't move the turret ( thus, is not allowed to verify by machining, nor by moving the turret, nor by moving the tailstock );* idea behind this is minimal alignment time, one-shot rotation
    ... once the spindle will be again parallel to z axis, there is a big chance for the spindle-axis and id-toolholder-axis to be parallel instead of being coaxial; let's say that by using a centro, you discover that missalingment is only among Y axis, and X axis is fine : to achieve coaxiality among Y axis, do you align the spindle, or the turret, or both ? pls, remember that turret alignment is ok

    - let's say that there was a 3rd crash : only tailstock is out of alignment, and tailstock axis is no longer coaxial/paralel with spindle axis; how do you rotate the tailstock, to be again paralel to spindle axis, without verifing it by moving the turret ? thus you should rotate the tailstock in such a way, that you will be sure that it is paralel to the spindle, even if you don't check it by moving the turret; you may move the turret to find the tilt before begining to rotate the tailstock, but you may not move the turret to verify the alignment after rotating the tailstock; * idea behind this is minimal alignment time, one-shot rotation

    kindly

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    Last edited by deadlykitten; 01-09-2020 at 03:42 PM.
    ... chip happens


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    Default Re: please, questions about lathe service

    Hello.
    All your questions are not for amateurs.
    Based on your questions, you are planning to renew an old CNC machine. This is extremely difficult for amateurs.
    Tuan.



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    Default Re: please, questions about lathe service

    Hey kitty, as they say...RTFM. The procedures you describe are in your Maintenance Manual. for alignments, start with the base and work your way up. The ways on the base are the "master" and everything else is aligned in relation to them.

    As far as verifying torque, use your load meters. They represent fully your motor draw for every motor.

    Best regards,

    Experience is what you get just after you needed it.


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    Default Re: please, questions about lathe service

    hy mr wizard yes, yes, the manuals ... i believe that i have failed to express what i mean, making it hard to understand

    when a turret is aligned on z, manuals sais to use a dial, like in attached image: rotate-the-turret + check-with-the-dial until inclination is < 0.03/100eq; this method involves repetition (rotate&check, rotate&check, etc), and after a few tries it will be ok

    what i was tring to ask : is there a method to get it (almost always) straight from the 1st try ? how to align a turret much faster, with less efort, compared to the procedure described inside the manual ?

    As far as verifying torque, use your load meters. They represent fully your motor draw for every motor
    ... a machine is not capable of driling as expected
    ... c axis is no longer holding the position
    ... break got loose
    * okuma's are great machines, and all these will be fixed soon

    by using a torque meter, some problems can be seen at an early stage, and avoid the situation when a machine is no longer capable of running a setup that was ok a while ago / kindly

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    ... chip happens


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    Default Re: please, questions about lathe service

    Sweep the face once and find the difference A-B. Then position 2 indicators and set them so that the indicators read the A-B difference. Then adjust the turret until they both read the same value. The turret should be straight at that time. Note: The indicators will both be moving so when they read the same they may not be at the value you expected since your are not "pivoting" between the 2 points. For example you may start at 0 and -.03 and end at +.011 and +.011, but the turret will be straight in relation to Z. Once it is straight, you will then need to re-establish X Zero point to the center of a boring bar holder since you most likely will not end up in the exact X mounting position with your turret as before. Find the difference in X center and then change your PR Zero Offset to make the encoder offset correction. That way you do not to change your zero Set numbers, variable limits, and Stroke end limit positions. They all remain exactly the same and only the PR Zero Shift number changes. Write it down on the management data card once finished and it proves correct.

    Best regards,

    Experience is what you get just after you needed it.


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    Default Re: please, questions about lathe service

    hy mr wizard thank you for your answer > : D <

    please, how do you manage the maximum force used ? for example, if you kick it too hard, then the indicator will lose contact with the turret, then come back ( eq: it shows 0.50, right after the kick it goes to 3 because of the shock, then comes back to 0.60 ) ... do you like 'jumpy' indicators ? and what tools do you use, like a plastic hammer, or something else ?

    also, please, how do you manage the minimum force used ? for example, if the difference between the indicators is only 0.04, how do you achieve a 'gentle touch', so to go smooth to 0.03, 0.02, 0.01 etc ?

    do you use a different approach for Y turrets ? is harder to align them, because the slant is more tilted, so more force is required

    That way you do not change your zero Set numbers, variable limits, and Stroke end limit positions
    yes, you are right, but i always change the limits, so to always have eq X+330 -140, Y+70-50, etc ... there is still clearance until the hard limits; i like them to be rounded, and also i no longer need to change the igf parameters for turret index X position / kindly

    ... chip happens


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    Default Re: please, questions about lathe service

    I usually leave bolts slightly snug with one “ pivot point” bolt tighter. It seems to make aligning with my precision alignment tool ( plastic dead blow hammer) easier and more controllable.

    If I remember the y axis has jack bolts on it for easier alignment but it may be different on your machine.

    Experience is what you get just after you needed it.


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    Default Re: please, questions about lathe service

    since last year, i started using a long shaft, like o40x500, inside the bore of an id holder

    i unscrew all bolts from the turret ( like 1 full turn back ), and rotate the turret down_max, then up_max ( thus i increase the missalignment ), so to eliminate the static friction, otherwise is harder to rotate the turret

    after that, i screw them back, just like you said, leaving one a bit tighter ( the one towards the tailstock, so to prevent the turret from tilting frontwards )

    i use my palm to tap the far end of the long shaft, always towards x-, so to use the help of gravity

    the shaft may rotate freely inside the id bore, and also move rigth-left inside the bore, thus i don't use the screws to secure it inside the holder, if the shaft rotates, then it means that i don't apply the force along the correct direction

    indicators are on the active turret post; id holder + shaft : one post above

    the key to make it work smooth, is to tighten the bolts only as much as it is necesary to prevent the turret from falling down, but still being able to move the turret by tapping the shaft; if bolts are too tight, then it will be required to apply too much force on the shaft, and since this is working like a lever, it may lead to some consequences / kindly

    ... chip happens


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