Master precision Machinist level

I'm not quite sure what he means by this. Is he talking about a literal perpendicularity to gravity's pull? That's kinda irrelevant.

Is he talking about day to day, month to month, year to year variation? If the lathe is bolted to a sufficiently rigid surface(the required rigidity being in proportion to the mass of the lathe), the lathe's level with reference to itself (i.e., bed twist etc.) will depend on that rigid surface not the variation of the foundations (absent some serious tectonic shift :D)

He's certainly got a point there, but if one is aiming to measure deviation from expected performance (as we all want to, when setting up any machine tool; or else we'd not bother with DTIs :D) it's handy to at least have a go at removing as many variables as one can.
If I understand what he was saying
Is giving the environment and the accuracy of the machine over all
It was well within tolerance
Im the biggest error at the moment.
 
it's handy to at least have a go at removing as many variables as one can.


Here’s how I think about variables……..

I don’t.

If I’m making a 1off part I could do this on a lathe that looked like a twizzler.

If I were making 100 pieces, it becomes a different story.

I’ve honestly never even considered wether a machine was plumb, true, level or anything, I just make parts.

I think there is too much “CNC” bleed in peoples thinking tying them up worrying about minutiae that realistically will never matter.

Make parts, have fun.
 
hshahahaahahadd I am getting the drift man ;)
Lol, did he post that twice or did you Bork the quote?

Either way, I think you’re getting it.

A co worker asked me recently why I put so much detail into some of my work, and I let him in on my most sacred professional secret.

Every fancy detail in a part that is not necessary represents an effup that I needed to cover vs making the part over from scratch.

Use this knowledge how you will.
 
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Lol, did he post that twice or did you Bork the quote?

Either way, I think you’re getting it.

A co worker asked me recently why I put so much detail into some of my work, and I let him in on my most sacred professional secret.

Every fancy detail in a part that is not necessary represents an effup that I needed to cover vs making the part over from scratch.

Use this knowledge how you will.
I took notes ;)
 
Here’s how I think about variables……..

I don’t.

If I’m making a 1off part I could do this on a lathe that looked like a twizzler.

If I were making 100 pieces, it becomes a different story.

I’ve honestly never even considered wether a machine was plumb, true, level or anything, I just make parts.

I think there is too much “CNC” bleed in peoples thinking tying them up worrying about minutiae that realistically will never matter.

Make parts, have fun.
Honestly, I get what you're saying. You know what's you and what's the lathe. You've got enough experience to be able to distinguish.

But, when someone's starting out, they don't have that basis of experience.

Do you not think it would be helpful if they were able to work out if a problem they encountered was caused by a poorly set up machine tool or a perfectly good machine tool that they're using poorly?

If you're learning, it can be pretty frustrating when you don't know the cause of the problems you're facing. ;)

Don't get me wrong. I'm not saying beginners (like myself) should go out and buy a ton of super expensive metrology kit to try to get their lathe set up so it could hit micron levels of accuracy.

I reckon Rollie's Dad is good enough for us beginners.
 
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Honestly, I get what you're saying. You know what's you and what's the lathe. You've got enough experience to be able to distinguish.

But, when someone's starting out, they don't have that basis of experience.

Do you not think it would be helpful if they were able to work out if a problem they encountered was caused by a poorly set up machine tool or a perfectly good machine tool that they're using poorly?

If you're learning, it can be pretty frustrating when you don't know the cause of the problems you're facing. ;)

Don't get me wrong. I'm not saying beginners (like myself) should go out and buy a ton of super expensive metrology kit to try to get their lathe set up so it could hit micron levels of accuracy.

I reckon Rollie's Dad is good enough for us beginners.
No, you're absolutely right, but confidence will only come with time turning handles. You have undertaken a very difficult hobby that will reward you if you put in the time. Plus, the learning curve is near vertical.

Trust me, its you, its me, its the guy across the room, this is why curse words were invented. Even if it is just simply the operator making a bad setup.

If its your very first month or year of running a given machine you have a good reason to have these concerns.

But to my mind, once you perform a process on a machine well, at least once, the machine generally does not change in a short enough timeframe for you to notice. Chipping an insert or losing the edge on a tool bit or endmill will change performance, but these are things that are generally understood and looked at when an issue arises.


Now to relate this to you or others who are just beginning, if you're having a problem, ask yourself "What's the variable" or "What is causing this issue".

Is it the machine?

Could be, but if so this will be shown as a repeatable problem.


Is it the tooling?

Might be, can you uncover something that is not right? A wobbly setup, something not tightened down correctly or as above, a bad cutting edge? A magnifying glass might be needed to uncover a flaw in a cutting edge you might otherwise see as sharp. Dull cutting edges can induce vibration, cause excessive heat (Did your chips change color?), or noise that was not there prior.

Or is it operator induced?

Many times it is, this is why I'm saying just make stuff. Pick something simple and just make it. A tool for the shop, a fidget spinner, mill your name in a piece of aluminum, then work your way up to doing it in steel. But for gods sake(<<<The Japanese wine) don't jump in with both feet in your first year and try and make a working miniature Ferrari engine.

Keep in mind, you, me, him are the least reliable thing in the equation, and some days are just not good days. Ill have days where I feel superhuman and everything goes my way. Other days I cant seem to do a damn thing right.

On the good days I roll with it. Ill get 4-5 good hours before becoming fatigued and things start to go pear shaped. Know when to say when.

On days where I'm just not doing well I find something that is productive where I can do less harm. Ill organize, clean, sort, draw up plans.

You have a desire to do this difficult thing we all like to do here, and its important to understand yourself and that some days you just don't have it. If something frustrates you just set it aside and come back to it rested and in a good frame of mind.

You'll get it.



BTW, who is Rollies dad?
 
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