Lathe parts / correct nomenclature...

[Tangledfeet]

As many of you know I'm a techie teacher and whilst I'm 'okay' with the basics of the centre lathe I do find myself having blonde moments... some qualified confirmation would be warmly received!

After months of lockdown (prior to summer holiday and now again since New Year) I'm starting to struggle to come up with online learning for a third year (as in they do the exam next year) practical metalwork class which is 70% practical and 30% theory - all we've done at school has been practical work as we'd concentrate on the theory next year. Last week's was an online quiz on MIG, MMA and TIG welding - even though they don't need to know about the latter!

First question;

Is the carriage the collective name for the parts that travel along the rails of the lathe and comprises the saddle, the cross slide, the compound slide and the tool holder?

And the apron is just the front of the carriage?

 

[pressbrake1]

Carriage is collective term

 

[RWD3M]

Whilst there is an undoubted wealth of knowledge here, you could do a lot worse than take a look at Tony Griffiths' Lathes website:

lathes.co.uk

 

[Arc Tourist]

Apron "is" the front of the carriage with the hand wheel and controls to engage the leadscrew ( if equipped) for threading.

 

[Tangledfeet]

Carriage is collective term

Thought so - cheers!

Whilst there is an undoubted wealth of knowledge here, you could do a lot worse than take a look at Tony Griffiths' Lathes website:

lathes.co.uk

Ta; am familiar with that website, even from just looking at the history of old woodturning lathes! I'm trying to be specific to the lathe(s) we have at school; Warco GH 1330's.

Apron "is" the front of the carriage with the hand wheel and controls to engage the leadscrew ( if equipped) for threading.

They don't need to know about cutting threads on the lathe at this level at school and (frustratingly for my own selfish 'homer' needs!) the leadscrews have been disabled on these lathes - they were used when they arrived several years ago!

 

[Ali]

Try this site, I think designed by a teacher - I’ve used it for training

The Centre Lathe

This site provides a wealth of technology information sheets for pupils and teachers

technologystudent.com

 

[Tangledfeet]

Try this site, I think designed by a teacher - I’ve used it for training

The Centre Lathe

This site provides a wealth of technology information sheets for pupils and teachers

technologystudent.com

Yup, we use that too - will probably use a page from it for this online task/quiz as long as the terminology marries up!

The Centre Lathe (technologystudent.com)

I'd refer to the 'top slide' as the compound slide.

 

[Tangledfeet]

I've distilled several paragraphs down to a few much shorter ones...


Headstock

The headstock provides the rotational power for the centre lathe’s operations and is driven by an electric motor and gearbox. As these Warco lathes have gearboxes they are referred to as gear head lathes, hence ‘GH’ in the model name.

Gearbox

The gear box is inside the headstock. The gearbox controls are mounted on the front of the headstock and control lathe speeds and the ratios for the power feed; this is where the lathe tool can be moved under power rather than by the lathe operator.


Tailstock

The tailstock slides along the rails on the lathe bed and can be locked at any location by a clamping lever. The tailstock has a heavy-duty spindle; this is a non-rotating barrel that can be used for supporting the non-driven end of the work, or it can be fitted with tools such as a Jacob’s chuck.


Lathe Bed

The lathe bed is made of high-quality cast iron and is very rigid. Two precision hardened rails provide the accurate guide for the headstock, tailstock and carriage.


Carriage

The carriage is made up of several parts that comprise the saddle, the apron, the cross slide, the compound slide and the tool post. The carriage is made from high quality cast iron and the sliding parts are very smooth. The cross-slide is mounted on the saddle and moves on a dove-tailed slide. The carriage travels along the rails on the bed of the centre lathe and is moved by the apron hand wheel.

• Saddle: the saddle sits across the rails like a saddle on a horse and travels along the rails from left to right.
• Apron: the apron is the front part of the carriage that faces the operator and the large apron hand wheel is used to move the carriage quickly left and right along the rails.
• Cross slide: the cross slide sits on top of the saddle and can be moved back and forth by the cross feed handle.
• Compound slide: the compound slide is mounted on the cross slide, can be rotated through 360° and clamped at specific angles, and has its own small compound feed handle for moving the lathe tool.
• Tool post: the tool post is secured to the top of the assembly and can hold up to four tools which are clamped in place using bolts.

 

[pressbrake1]

It’s funny I say compound, pal say top slide
I say headstock and tailstock, my late father called them fast head and loose head

 

[Seadog]

And don't forget Changewheels, not change gears.

 

[Tangledfeet]

And don't forget Changewheels, not change gears.

Way, way beyond the scope of what they need to know at this stage.

 

[Ali]

Bed - or ways?

 

[Agroshield]

Gearbox

The gear box is inside the headstock. The gearbox controls are mounted on the front of the headstock and control lathe speeds and the ratios for the power feed; this is where the lathe tool can be moved under power rather than by the lathe operator.


Tailstock

The tailstock slides along the rails on the lathe bed and can be locked at any location by a clamping lever. The tailstock has a heavy-duty spindle; this is a non-rotating barrel that can be used for supporting the non-driven end of the work, or it can be fitted with tools such as a Jacob’s chuck.


Lathe Bed

The lathe bed is made of high-quality cast iron and is very rigid. Two precision hardened rails provide the accurate guide for the headstock, tailstock and carriage.


Carriage

• Cross slide: the cross slide sits on top of the saddle and can be moved back and forth by the cross feed handle.

A few comments FWIW.

Is it worth making the distinction between the gearbox used for changing spindle speeds and the other gearbox used for selecting screw-cutting pitches? If you like, upper and lower gearbox on the GH1330.

Consider abolishing 'spindle' from the tailstock description. A spindle rotates, an undesirable quality of a tailstock. 'Quill' or 'barrel' as you have is good.

Beds for sleeping might have rails. Lathes do not. 'Ways' is a better term.

Perhaps emphasise the point that the cross slide can only move perpendicular to the lathe axis, whereas the compound, as you say can go in any direction.

 

[Tangledfeet]

A few comments FWIW.

Is it worth making the distinction between the gearbox used for changing spindle speeds and the other gearbox used for selecting screw-cutting pitches? If you like, upper and lower gearbox on the GH1330.

Consider abolishing 'spindle' from the tailstock description. A spindle rotates, an undesirable quality of a tailstock. 'Quill' or 'barrel' as you have is good.

Beds for sleeping might have rails. Lathes do not. 'Ways' is a better term.

Perhaps emphasise the point that the cross slide can only move perpendicular to the lathe axis, whereas the compound, as you say can go in any direction.

Some good points there - many thanks.

Gearbox - yes, will mention that but they don't need to know about screw cutting on the centre lathe; beyond the scope of the course.

Spindle - good point.

Ways - know what you mean but I think 'ways' is more of an American term and not one I've ever seen mentioned in any exam papers written by the SQA (Scottish Qualification Agency).

Cross slide - yup, will clarify that and put it in simpler terms than 'perpendicular' as it'll be beyond their volcabulary!

@Agroshield Much appreciated!

 

[Fastdruid]

Bed - or ways?

Er, technically both. Bed is the structure, ways are the part of the bed that the carriage runs on. Although of course with more modern stuff they may actually be rails instead.

Personally I would consider ways to be a fixed part of the bed while rails would be something bolted on, ie linear rails.

 

[Shox Dr]

It’s funny I say compound, pal say top slide
I say headstock and tailstock, my late father called them fast head and loose head

I was taught the top slide sits on top of the compound (also known as a Compound slide.)

Personally I would be looking at lathe technical descriptions from 40+ yrs ago for the original 'correct' naming.

 

[Tangledfeet]

I was taught the top slide sits on top of the compound (also known as a Compound slide.)

Personally I would be looking at lathe technical descriptions from 40+ yrs ago for the original 'correct' naming.

The SQA use the term compound slide so I'll stick to that as it'll be what they'd use in an exam.

This is actually all they need to know at this level, I know @willie.macleod teaches more engineering skills up there in the islands. This is freely available from the SQA's website so I'm not sharing anything that's beyond the reach of pupils:

 

[Shox Dr]

How are they taught to use a chuck key ?

 

[Fastdruid]

No mention of universal milling machines? Disappointing!

How else are you going to do helical milling? (lets not even get in to Wikipedia considers a "universal" to be a machine with a vertical and horizontal head).

 

[Fastdruid]

How are they taught to use a chuck key ?

By having a very conspicuous patch on the door opposite the lathe and telling all the students never to leave the key in the chuck as someone did it once and it went right through the door... At least that's how they did it at our school (I never got to play with the lathe there, I don't think they let any of the pupils until sixth form).