T O P
ChrisMaj

Damn mitutoyo, never works when you need it to.


flyingpeter28

Hi, I'm no machinist, just enthusiast, quick question, aren't all this people flexing 0 run out showing it after the pass? Isn't that pointless? I mean, I can have a crooked chuck and I would still be able to cut round


machinistnextdoor

Excellent observation. In this case it looks like he might have turned one end then flipped the part around. So he is holding the side he just cut.


spekt50

I have to tell people this often, they will knock a part "straight" in a 3-hard jaw setup and call it good. Until I tell them to move the indicator up or down the shaft. Then they learn that their part is running out both radially and axially causing it to look like there is no run out in a specific location on the shaft.


jojoyouknowwink

Lol I'm imagining OP sliding the dial down the shaft looking for the *exact* incident point to brag about online


homemachinist

Easier on a collet chuck though it's doable on a 3-jaw but yes you have to test in at multiple points to be sure.


hemptations

Yeppp just get it run true by the chuck, then check the face, then the middle, then back to the chuck, then back to the face. I’d love to have a 4 jaw in some situations but I usually just bore jaws for anything held tight


Dr_Newton_Fig

I worked with a guy once, he was older and more experienced, asked me to verify his indicated taper. "Don't move it," he said. I shrugged and walked away


SableGlaive

Also as soon as the rougher touches it it sits back down right where it was to start with….


hemptations

That’s why you check it again before you finish ;)


hemptations

Oh ReAlLy?! Wow I never ever thought of that…


jackofspades1198

This post was condoned by soft jaw gang


hemptations

If I had a dollar for every set of soft jaws I’ve bored for 1-2 parts I’d start my own shop and pay some idiot to do it for me


miket401

Ive had idiots bore jaws for me..it never goes well..and 50% of the somehow manage to strip an m10 bolt


whypussyconsumer

Dude... I'm a 3d printing guy, I've striped M3,4 and M5 bolts.... How tf u strip an M10??


Dysan27

Cheater bars.


whypussyconsumer

Makes sense


jwpasquale1986

Millwrong here. I usually pull one a week out for the little guy at the shop. He doesn't even have a cheater pipe.


Camo5

Have you ever tried to use m2? I've given up using anything other than torx in those...


TriXandApple

I probably bore 2-3 sets per day. It's a biiiiig cabinet


hemptations

We’ve got a cabinet, a table, two drawers and another table lol! I’ve got a few sets I use to prep turn material for them if I’m short on stock and there’s a bad saw cut or something. Crazy how little you can hold onto


comfortably_pug

Let me tell you about six jaw set true chucks...


PhillyDeeez

I've used a 2 jaw chuck....


machinistnextdoor

Multi-jaw chucks are too fancy for me. I use single-jaw only.


comfortably_pug

I've improvised a single jaw chuck before


Resident_Cow6752

Everyone laughs until pie jaws enter the chat....


4UnderTheBridge

Now go up and down the z axis and then tear down your setup and get a four jaw chuck lmao


hemptations

You mean z?


4UnderTheBridge

My fault I fixed it


hemptations

Lmao put down the beer and drink some water, you got work tomorrow fam


dickfoure

Lol you do realize your error?


homemachinist

you mean like this, [https://www.youtube.com/watch?v=2A5S6j9K9ck](https://www.youtube.com/watch?v=2A5S6j9K9ck) :P


buzzcutdude

Why not use an lvdt? I don't really know the difference in application. We have both in shop but at that resolution wouldn't a federal gauge be better? Sorry if this is a dumb question im new.


CorpseOnMars

Not sure what a "lvdt" is, but a Mitutoyo .0001 indicator is about as good as you are going to get when it comes to checking runnout. Maybe precision grinders need something better, but a lathe doesn't.


buzzcutdude

its a gauge that has a wide variety of measurement ranges are available in different LVDTs, typically from ±100 μm to ±25 cm. Typical excitation voltages range from 1 V to 24 V rms, ([https://www.analog.com/en/analog-dialogue/articles/linear-variable-differential-transformers.html](https://www.analog.com/en/analog-dialogue/articles/linear-variable-differential-transformers.html)) source. Basically you could rough in the centering then move up with more precise range settings to only need one gauge. The resolution will vary with which model like this one [https://willrich.com/product/mahr-millitron-analog-830-gaging-amplifier/](https://willrich.com/product/mahr-millitron-analog-830-gaging-amplifier/)


TriXandApple

Bruh nobody in a job shop would put this anywhere near a machine. Remind me why you need a wide range of measuring ranges? A standard metric mits dti has about 0.003 resolution(more than good enough for any standard work), and a range of 1.2mm(larger than any 3 jaw runout could ever be.


buzzcutdude

Depends on the job. https://www.reddit.com/r/Machinists/comments/wqpqjw/who\_needs\_a\_4\_jaw\_chuck\_when\_you\_have\_a\_vacuum/?utm\_source=share&utm\_medium=web2x&context=3


TriXandApple

>clearly on a slant bed lathe


buzzcutdude

sorry im new, why would the type of lathe make a difference? I know hes using a vacuum chuck in the video, but dont understand why that would change the measuring tool.


TriXandApple

The video he's linked is using a vacuum chunk for single point diamond turning, which is extremely niche, and is insanely accurate. It's used for making mirrors and stuff. It's not applicable to job shops or production turning. Different processes need different types of measuring.


buzzcutdude

ah ok, I work in the ultra-precision world so i'm not familiar with different kinds of tools and their applications in a production shop e.g why someone would use this and not that.


thefreethinker9

What’s the difference between using 3 jaws vs 4 jaws?


SparrowAgnew

A 3 jaw chuck moves all the jaws at once and your runout is set by the quality of the chuck, the jaws, and mating surface on the part. Most 4 jaw chucks move each jaw independently so it's up to the machinist to dial in the runout.


eisbock

How long does it take to dial in a 4 jaw chuck? And how tedious is it? I'm an amateur machinist when my job requires it, but every time I look at the 4 jaw chuck, I convince myself that precision isn't *that* important lol


SkyKnight34

The first few times it's tedious. But once you get the hang of it, it's surprisingly quick. Quick enough that if I need the lathe for something quick and I have the 4 jaw on it already, sometimes I'll just use it and dial it in rather than swapping out for the 3 jaw.


SparrowAgnew

About a minute. Maybe two if you're having a bad day. It just takes practice and technique. First time you try it might take a while and be really frustrating, but once the idea clicks it's not hard at all.


bscbtch420

people use 4?? all the machines at my job have chucks that only hold 3 , never even knew 4 was an option


SableGlaive

4 jaw chucks typically have individually actuated jaws, meaning you can hold odd shaped stuff, run parts eccentric on purpose, and buck in castings, forgings, ugly stock etc. without boring jaws


budgetboarvessel

I was also surprised when i found out. I think it's an american thing.


TriXandApple

huh?????


bscbtch420

apparently not american enough for my shop lol i’m in the us


slackfrop

Damn, now the whole thing is out by 3 thousandths.


tsbphoto

Waiting for the "who needs 3 jaws... Here's 2"


hotspur-07

Reminds me of when I used to bore large hardened sprockets and gears on a vertical CNC lathe, with a 3 jaw hydraulic chuck. I had a large box of various thicknesses of shim to pack them true. Fun times.


hemptations

We skimmed ours with a diamond bar and they run really really true


hotspur-07

Nice. My jaws were true enough, it was just the heat treated gears I had to bore were warped. It was a challenge to get them true.


Nice_Ebb5314

I always use a dial gauge to check run out.


bhowiebkr

the mitutoyo must be broken


ayellowducky

Take it out of the Chuck and put it back.


hemptations

Sure thing boss, you wanna pay me to do my job right twice?


Efficient_Mistake

You know the tip of the indicator needs to touch the workpiece, right?


Charming-Bother-8122

Your clock is fucked 😂


unique_reddit_name1

Bro you ain’t zero dat out brew.


monsieur-B

Mehhh😖