Hi,
As a 'NEWBIE' to Hobby engineering, although I have watched others doing lathe work, I would like to ask a question regarding Imperial and Metric machining.
I believe that most Imperial lathes have their 'Slide' screws threaded in an ACME size, usually 10 TPI, thus allowing the dials to be calibrated with 100, or even 200, divisions. Thus 1 Division would give a 1 thou travel of the slide. However, does a Metric machine (Lathe) have its 'Slide' screws cut with a Metric Pitch, i.e 10 threads per 1 CM ? If so, would the dial still have 100 Divisions, or does it have 10 or 20 divisions?
Also, are there any dials that are calibrated in both Imperial and Metric, which are not the really expensive geared dials? Could a dial be obtained with 100 Imperial divisions and also 25.4 Metric divisions?
I ask this as I am attempting to help a Disabled colleague restore his Mini Lathe. That lathe was originally Metric, with the compound slide having an unusual threaded screw sleeve running along one side of the slide. There is no provision for a Central type screw nut. The problem that we have hit is that the screwed sleeve, together with the Slide screw, are both badly worn. The Compound slide screwed sleeve does not have enough meat on it to insert a bush in order to re thread it to its original Metric size, although it could be bushed in order to accept a smaller Imperial size. The cross slide is not so much of a problem, as a New screw and nut could be made, although we would like to make both screws in exactly the same sizes.
I realise that the above questions may seem a little weird, but any advice would be greatfully welcomed'
By the way, I am in the UK.
Many thanks,
As a 'NEWBIE' to Hobby engineering, although I have watched others doing lathe work, I would like to ask a question regarding Imperial and Metric machining.
I believe that most Imperial lathes have their 'Slide' screws threaded in an ACME size, usually 10 TPI, thus allowing the dials to be calibrated with 100, or even 200, divisions. Thus 1 Division would give a 1 thou travel of the slide. However, does a Metric machine (Lathe) have its 'Slide' screws cut with a Metric Pitch, i.e 10 threads per 1 CM ? If so, would the dial still have 100 Divisions, or does it have 10 or 20 divisions?
Also, are there any dials that are calibrated in both Imperial and Metric, which are not the really expensive geared dials? Could a dial be obtained with 100 Imperial divisions and also 25.4 Metric divisions?
I ask this as I am attempting to help a Disabled colleague restore his Mini Lathe. That lathe was originally Metric, with the compound slide having an unusual threaded screw sleeve running along one side of the slide. There is no provision for a Central type screw nut. The problem that we have hit is that the screwed sleeve, together with the Slide screw, are both badly worn. The Compound slide screwed sleeve does not have enough meat on it to insert a bush in order to re thread it to its original Metric size, although it could be bushed in order to accept a smaller Imperial size. The cross slide is not so much of a problem, as a New screw and nut could be made, although we would like to make both screws in exactly the same sizes.
I realise that the above questions may seem a little weird, but any advice would be greatfully welcomed'
By the way, I am in the UK.
Many thanks,