Common Machining Mistakes
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- Опубликовано: 22 ноя 2019
- This episode on Blondihacks.com, I'm talking about common machining mistakes that all beginners encounter! Exclusive videos, drawings, models & plans available on Patreon!
/ quinndunki
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A note on mistakes made early: Back in the early 1950's my pop worked with a toolmaker who had been working on a very complex part for the Nike Ajax air defense rocket for over two weeks. The toolmaker went into the bull's office with a downcast face and said he had scrapped the work. The old man put his hand on the toolmakers shoulder and told him it was alright and not to worry. "Go ahead and start over," he said, "but this time if you're going to scrap it, don't take so dammed long!"
Cheers from NC/USA
InstaBlaster.
For center punching, If you really need it to be precise, grind down the end of a small piece (
an optical center punch is also an option, though more involved to DIY
I'm a full-time lathe operator, and I do a surprising amount of measurements with my calipers. One way I improve the accuracy of them, is by using a gauge block set to "zero" them, or more accurately calibrate them, in the vicinity of the size I am going to measure. Say I am turning a final diameter of 1.875", then I grab the 2" gauge block and get that dead-nuts; that gets me quick measurements with a reliable precision of maybe .0003" or so! These are good quality Mitutoyo calipers, which also helps. If I need better precision (I sometimes get tolerances that demand .0001"), then I do similar checks with the micrometer. Say the 2" block reads 2.0004"; then the actual dimension is four-tenths smaller than the reading. It's possible to calibrate the barrel also, but it takes time and some of those older ones have really sticky barrels, so in practice I just keep the correction factor in mind most of the time.
Excellent comment we use this method everyday in our shop. Gage blocks are the best way but you can also use pin gages. Mitutoyo makes very good measuring instruments. Our shop is full of them. Having own Mitutoyo, Starret, and Brown and Sharpe dial calipers IMO Brown and Sharpe makes the best calipers. They've held their accuracy the longest in my box. Calipers are the only tool I like from them.
@sexiewasd Cool I haven't tried that one. I rarely use squares. I've tried their od and depth mics and didn't care for them. I am a big fan of those calipers though. Most of my box is Starrett (real Starrett not that Global stuff) except my calipers and indicators.
Excellent This Old Tony impression.
Was about to ask if these two are brother and sister?
One of the best bits of advice I got was from Abom - don't look at the gauge on the calipers or micrometer as you're measuring to prevent that bias, forcing the tool into the measurement you're looking for
That’s a great tip. Adam is the best
Biggest and most common mistake I see students/beginners make is alignment of measuring tool to the surfaces to be measured. Which you covered. Good job.
Quinn,
Regarding micrometer feel;
Grab a feeler gauge set, set the mic to 0.004” for example and pull a 0.004” feeler through the mic. Pretty good so far, eh?
Now set the mic a half a thou under, feel what too tight feels like, set half a thou over and feel too loose, immediately return to just right to reinforce the lesson.
Next, select the thinnest feeler gauge of your set, often it's 0.0015” or 0.002”, this one should push through the mic's anvils without buckling. Caution, if the mic is set too tight on these thinnest feelers they are subject to tears. (tears pun unintentional).
Repeat daily or weekly until the mind/muscle interface is adequately programmed.
Side benefit, you've also just programmed your feeler gauge 'feel'.
Nifty innit?
From a old mechanic hoping to pick up on some machining.
Two Blondihacks videos on one day?! You're not drunk, this is happening. This video needed to get published right now, for reasons you'll see at the end. Enjoy the two-fer! 😀 Consider it a gift of appreciation to all my awesome viewers. Or perhaps an American Thanksgiving Miracle, if you're into that sort of thing. 🦃
I just finished watching "Let's make soft jaws".... Do i dare watch more train wrecks today ? 😵
well.. I am drunk... but still
ToT sent me here and I'm glad he did. Very well done. I'll certainly stick around.
Being an old, emphasis on old racer I love the metaphor. Having some experience with machining (retired gunsmith) I really like your approach. It's not simplified exactly but very easy to understand. It never hurts for old dogs to refresh the memory banks from time to time. I like what you are doing very much.
I found another mistake. You didn't say "tappy tap tap" 9:26
.
Patryk Buczyński My observation also,but once Quinn admitted to being a human running a machine,makes not catching her centre punch error quite understandable.Hopefully Maho Man can help her out once he does his part in the rebirth of Johnny 5.😆
I got my AvE hoodie in this week yeeyee
That was the mistake at corner 3.
@@schlomoshekelstein908 why are you so obsessed with what's between Quinn's legs? The rest of us are able to focus on the topic at hand. Hmmm... you got something you want to share with the rest of us? You're so deep in the closet you're finding Christmas presents, boy.
"Hey Tony, fix these parts for me, would ya?" Love it
At 9:45 I thought you were going to mention the additional (deliberate?) marking-out mistake that each scribed line measurement is is being referenced to a different datum edge.
As I'm sure you appreciate, if you want four perfectly spaced holes then it is best to measure and mark-out all their positions relative to just two of the block's edges.
[Or more pedantically, all measured in same coordinate system, as defined by three perpendicular reference faces meeting at one corner of the stock. ]
Otherwise, by taking each measurement relative to a different side of the block, the machining tolerance errors on the stock size will get added to the hole spacing distances, and will make them less accurate.
(Yes, this is a mistake I have made myself)
Good CAD drawings will have "Datum feature symbols" on them to tell the machinist which are the part-faces that all of the dimensions should be measured from.
Yes, totally fair point- measuring inward from different edges is a big no-no. I was just trying to contrive a way to demonstrate punch mark moving.
@@Blondihacks ah ha! I was going to ask why you didn't use an edge finder.
Excellent Quinn, if I may suggest an aide to ensuring holes are on dimension, scribe a circle using a pair of dividers slightly bigger than the required hole, this shows its position, before drilling, and at the start.
Never heard of "Pleasant dimensions/numbers" before 🤗.
Thanks for sharing.
Just adding an additional proviso, to the use of the ‘ratchet’ knob on a micrometer. Don’t be tempted to use it to ‘rapid’ the mic down to the final measurement, as the mass/momentum of the approaching anvil face, can also apply a clamping force greater than the ‘ratchet’ would have applied.
At the end hand shot, I was thinking to myself, "This reminds me a lot of This Old Tony"
Many people don't realize how much feel is involved in conventional machining, when sneaking up on a final dimension, for example:" Yes, YES, ohh, yes! yessss...."
Quinn, As a newbie thank you for showing me the simple mistakes that I will endeavor not to replicate. I appreciate the teaching method you use. State the issue, show the issue, review the issue... throw in the self deprecation and humor.
Love your videos, I'm an amateur machinist raising two girls and it is refreshing to see a lady machinist to inspire my girls.
Among my multitude of roles at my shop, I am also the specialty welder.
So, I see in-shop and out-shop mistakes and reworks often. In our case, it's typically cost effective to have a guy like me try to save a part that has a lot of machine hours into it, not to mention the cost of the exotic stock materials (specialty steels, Beryllium alloys, etc). Typically, that means hours of LASER or GTAW welding to bring things back. All that said, preventing the "hurt" early, as you rightly said, is the best way to avoid thousands of dollars in welding bills and rework.
If you're going to the trouble to scribe your layout for your holes, you should use a prick punch to mark the intersection of the lines. As you note, you can definitely feel when the point is at the intersection of the lines; then you give the prick punch a *light* tap to mark the position. Then you come back with your center punch, either automatic or manual, and mark the center with a more confident tap of the hammer or triggering of the auto-punch.
The prick punch is lighter than a center punch and is ground with 30º included angle to the point. It's purpose is to make a light indentation to preserve a layout for future use or to receive the points of a divider. A center punch is ground with a 90º included angle and is intended to serve as the starting point for drills. A center punch will pick up a prick punch mark much more positively than it will the intersection of scribed lines.
I’m new to your channel. I’m loving your video on measuring and your honest answer to common problems with measuring.
I have a passion for machinery and working on machine tools.
I’m really glad you are invested in your craft.
It’s not easy teaching measuring and how to troubleshoot when the measuring process is seemingly working properly.
When I used to work in the machine shop we developed feel for the amount of drag on a caliper or micrometer. I’m saying that you can sense the amount of torque on a given part measurement.
Good job keep up the lessons.
Thank you for TWO videos on the same day, I'll consider it an early Christmas present. Yours is one of the best channels on you tube informative , witty and good entertainment I look forward to many more .
Thank you very much for the kind words! 😁
I was a teenager when dad showed me how that little knob on the end of a Starrett micrometer ensured accurate and repeatable measurements.
He was born in 1911 and passed away in 1993. But I still have his micrometer set.
I think I must have fallen into a fuzzy-edged fantasy land where there are two Blondihacks videos in one day... and while I am a little tipsy because Saturday afternoon doing laundry with wine (er, while drinking wine) I do believe that this is really happening. One of the great GREAT things about this channel is that goof-ups are acknowledged and informatively explored in a charming way. Failures are incredibly instructive. I mean, I'm glad it's not all goof-ups around here, but when they happen, they make good content. Also, bluing stock for marking is oddly satisfying to watch. I just checked in with Tony and he's doing a Jony Ive antenna thing... turns out that the Apple design grandmaster was a robot all along. I knew it!
When I was a Physical Dimensional Laboratory Technician with the National Bureau of Standards, I calibrated hundreds of micrometers. The higher end units included the Torque Knob on the handle end and are designed for it to be used for all measurements to insure repeatability. You only tighten them to 1 click.
During calibration, they are "run" three times through span tests for accuracy and repeatability throughout the entire measurement range using Lab Standard Gage Blocks. When using, it's always advisable to take the measurement thrice, and if possible rotating the micrometer so the stock under test lays across the anvil at a different angle for each measurement. that gives you the best chance of negating any deviations in the anvil surface, the most common being lack of parallel from a mic that had the knob torqued too tightly onto an irregular surface, and trust me, it doesn't take much force to tweak the anvils out of parallel.
Haha. I must confess I, like many other public school grads, have always had a tough time “factoring prime numbers.” Lol. (Your comment made me laugh.)
I've searched but I'm not seeing Tony's follow-up video? 😁 This is a great video. Thank you!
Hi Quinn i am a full time operator mill and lathe traditional than 10 years and i have a shop laboratory on my home,you are very good professional operator and i love your video,you are the best (sorry for my bad english......)
Wiping your surfaces should become a subconscious action. Great video, new subscriber.
Man, I learn a lot from this channel. Thanks Quinn.
Love your delivery Quinn.......always great stuff....Cheers, Paul
Moving center punch is a freaking magic. Thanks.
More helpful information, in fact, twice as much!. Thank you Quinn!
Never knew I could move the mark with the center punch. That was a very helpful tip! Thanks
Fierceflyer, you should try a Veritas Optical Center Punch from Lee Valley Tools. It's increased my precision 10-fold.
You can move most anything if you hit it hard enough.
Let's call the anvil of a micrometer the 'shoulder'. That way we can remember to not let there be a chip on our shoulder.
First time watching, really enjoyed the tips. Nice video, sound and teaching!!
This Old Quinn! Excellent! 😄
Lots of thanks and gratitude to you Blondie for your videos. You are helping the next gen catch the manual machining bug. Your vids are different than the "other guys". I hope as viewers we adequately communicate to you our thanks. Paul D.
Aww, thank you for the kind words, and for watching!
@@Blondihacks You are on a sacred mission to pass on the skills to the next generation of Jedi!
Wait, I am not implying you are Yoda!
TOT never did it! He would have used the time machine to post a video showing Quinn how not to make the mistake, she didn't, so we never saw this video! [edit] Honest - hadn't seen Tony's video yet when I wrote that. Waiting for a serious time inversion or something to happen 😕
I bought my vertical mill so i could use a edge finder so i didnt need to center punch,lol not to mention tapping holes
Professional machinist speaking here,
What I've doen in my apprenticeship (and still do every now and then when handling a new measuring device) is take calipers and and micrometers and just measure some gage blocks. It's great practice to get feel for the measuring force just right since you already know what the reading is you want to see. (When measuring a gage block and your reading shows something else than what the gage block is...trust the gage block...)
Hi Blondi, unless you you read your 1yr videos. When I 🤔 finished my career, I worked in aerospace/aircraft engines. For 9yrs my digital calipers, were used for ID / OD measurements. I haven't touched the good old mechanical stuff, and walked away from those. I'm a digital person now. I'm glad that you have included microns during your
current videos. Very nice 👌.
A double feature that *also* presages a ToT vijayo. I have not been living right enough to deserve this.
@11:00 When making standard pneumatic slide plates for my hydraulic crankcase I tend to use a different method. Wherever possible I use the milling machine itself to measure rather than marking and centerpunching. I just use the smallest centre-drill (from the lathe) that will fit in the chuck and drill the center holes, using the machine's dials to move the correct amount.
I'm not a machinist, just a hobbyist with a $800 Chinese CNC but it just seemed the logical way to do it. Besides I've never have a rocket ship blow up on launch for hydraulic failure so I can't be doing it that wrong.
This is my first Blondihacks video I have watched, and I am just starting to look into machining. I'll be honest, though I am still not 100% confident in this, it took me until the end of the video to realize that it may not actually be common for that first part to be recognized as valve stem from a magnetic flux pump. Great video, and good information. The This Old Tony reference made me laugh, you got yourself a subscriber. lol
Thanks for watching! I have an two introductory video series on machining, if you’d like to see what it’s all about. Check out my Lathe Skills and Mill Skills playlists.
@@Blondihacks I will check those out, thanks!
Yep the part is used to modulate the flow into the flux capacitor.
Ha!!
Lots of funny bits in this one.
Good tips too.
More collaboration, Yay!
Thanks and Meow.
Hi Quinn, good informative demonstration of how things can go wrong. I fully agree that so many errors are made several steps before the realisation sets in, (time wasted too) So, assuming my marking out is correct I have lately (3yrs) adopted the use of an :Optical centre punch' mine is a Canadian Veritas type and it's the muts nuts, if used correctly very accurate. Can't remember what I paid but very affordable cost if I recall. Great tool and wouldn't be without it now.
Yes reference to Old Tony ! Love it .
Really enjoy your channel. Very nice job my friend.
Thank you, and thanks for watching!
Excellent job!
You’re gonna ruin us, two videos in 1 day. Keep ‘em coming, great stuff.
Optical punches are a great way to ensure the center punch is on the cross lines. Easy to use and work every time!
This is the first time I have ever had someone say to use the ratchet for final adjustment !!! I always wondered "Why the hell do the put it on there if not to be used " .... Thank you !!!
I have watched this 14 times, maybe pie times E times pagedn72 squared, and gawd love it. Next caller.
Good sense.
A hydraulic foot lapper junction support angle adjustment lock is also with respect to pin parallelism 😊
I've found that the cause of most of my mistakes is not getting new glasses.
Ooh, I have another one. As you point out, an inch mic has .025" between each rotation, and it can be easy to misread by 25 thou. So do a quick sanity check: read the micrometer using the inside measurement points on you dial caliper, and if it's a couple of thou off that's fine but if it's, say, .023 off then look really closely at that mic barrel.
Oh yeah, also, if your mic has a tenths vernier scale, make sure you are really looking at the zero line and not at the bottom line of the vernier! I have screwed up parts that way, and it's super embarrassing. You think you're dialed in to the tenth, and you might be out by a few thou!
As someone who is fluent in metric, I can tell you that you're really quick on misreading by .5mm on micrometers. Another easy fix to that is just measuring the part with both your micrometer and the calipers: quick measuring with calipers to be sure you're in the right ballpark, and then the micrometer to be exactly on point.
Another thing you might not amount for when turning or milling is cutting pressure/cutting flex.
I work as a machinist and sometimes have parts where I have to use a boring head to make a hole within about ~0.02mm tolerance, sometimes in stainless, sometimes in cold rolled steel. (as an example, that's just 1 operation I have to do on those parts)
Now if it was only 1 or 3 parts the sane thing to do would be make pass a bit smaller than needed with the boring head, then a spring pass to eliminate that flex and then dial in the final dimension and maybe another spring pass if you're still abit under.
That's not really viable if you have to do 150 of those, so I'm dialing in the final dimension on the first load that it fits without the "flex", then look how much I'm under with the load after, take note, finish that load with a spring pass and then dial in the amount I was too small on top of the final dimension to be able to be on dimension after the first pass, as that saves a buttload of time (I'm usually dialing around ~0.02-0.03mm bigger than needed to be on point)
Also note that if you're switching materials (from stainless to cold rolled for example) you need to redo that setting up part, or else you're going to overshoot aswell
great video! cant wait to find out
Another great, informative video. Always look forward to your offerings. One question though. Is there a way to calibrate the thumb wheel on OD mics? I've found that some seem either looser or tighter than others. My thoughts are that using the thumb wheel will assist with repeatability but won't necessarily guarantee accuracy.
There is no need to calibrate the thumb wheel torque on a micrometer. It is the same torque/force that zeros the instrument that takes the measurement. As William Eades notes, use only one click. I have used more but the same number.
To preserve the accuracy do hold the tool by the plastic tabs or covers on the bridge. That way your body temperature will have less of an effect.
One of the other joys of a Blondiehacks video is the quality of the comments. They inform or ice Quinn's cake.
In my practice calipers are a fraction of the price of a thumb wheel micrometer so I use them accordingly.
When zeroing calipers I hold them to the light to check the jaw geometry.
For measuring smooth surfaces I use the knife edge section. Less chance of dirt interferance. The broad face is used for 'rough' surfaces.
I use calipers for measuring, not for marking out. As the jaws wear the line will be less accurately located.
Although several users claim to read sub thou measurements, and I have, from memory Mititoyo claim 3 thou absolute. (Pg 372 for metric)
When using micrometers hold them by the plastic section to stop thermal changes. Less likely in this audience but when using large micrometers zero them at the same attitude as the measurement to account for tool flex. Using gauge blocks for a near known measurement is a great idea. Saves wear and time.
With guides one can only locate a centre point to about 2 thou apparently. I would locate 0,0 at one corner and work in the same direction across the piece, doing each hole completely, and relocating by the hand wheels. It does mean redimensioning the drawing to suit absolute dimensions rather than relative ones. Oh, for a DRO.
Now off to another Blondiehacks!
Thumbs up for setting your racing analogy at Laguna Seca.
Good eye 😁
In the same class as this old Tony love your channels
"Like" the Back to The Future references. Clever!
Love your videos, Quinn!
Quinn, found this video today. Thanks for page 762, it is still there in the 30th edition. I look for TOT time travel sections in same book but Tony must have a limited print edition.
When I saw that chip on the micrometer, it drove me crazy!!! "Get it off there!" (I gotta cut down on the caffeine!) 😆
I use the machinists mitotoyo verniers as a chipping hammer after a hard days stick welding... I have been told that this has caused a few undersized parts too. 🤪
Nice setup to TOT latest. You two are my favourite youtubers and machinist-entertainers. ( Spelling of favourite is Canadian, in case you were wondering. It's a northern genetic thing )
errors happen.. keep up the good work and always improve.
just an observation, as you have scribe lines touch the center drill enough to make the circle and double check, your eye can see if it is off and needs to be moved... never be in a hurry to get it wrong ( it's a human flaw that everybody has )
All good advice there is defiantly a skill to using a micrometer
Ah, the old Off-Center Center Punch Trick, I always swear I'll never do that again, and again, and ...
I hope this is the first in a series of Common Mistakes videos...
It could be, if people are interested!
@@Blondihacks I could totally see that being a useful series. I haven't looked at the video titles for your as-yet-unwatched videos to see if you've already done it... if not, maybe through it into the idea mix? :)
Great advice!!!!
Machining Noob here, but another mistake that's easy to make is using a bad reference. For example, I just made a 3/8-24 chuck adapter for my Taig Lathe, but when I tried it out it was horribly out of alignment. So, I cut off the thread, turned it down, and tried again. And it turned out to be misaligned again. But, it was misaligned by the exact same amount at the exact same angle, despite me being much more careful this time.
Fast forward a half hour of futzing with some indicators and it turned out that what I made was concentric to 0.01mm or better. But, my brand new Jacobs chuck was out by about 0.4mm.
I'm still waiting on getting a replacement chuck, but at least now I know to be extra careful, and to use trustworthy references when checking my work.
Also, Hex dies are a pain to use (even ones that are not just for thread repair) and I wish I'd known that before I got my tap and die set.
Sounds like some extra tactile safecracking stuff with the feel for the crossing on the "x" with the layout fluid. I'm not quite up to that level yet that I can feel the slight detent mark it makes.
Thanks Quinn
Hi Quinn, love your videos and your presentation style, would love to see you make something, how about making a WigWag engine?
You bet! I’ll be doing more making of things soon.
@@Blondihacks Awesome! I look forward to some 'make' vids, keep up the good work :) Ade
I only use a centre punch when hand drilling. On the mill I use the DRO (or handwheel dials). Is this bad practice?
Not at all. The DRO is going to be better every time. Not everyone has one though.
I'm always impressed when people show their mistakes Quinn. Lets the rest of us learn. On the mill that second part could have been made by x-y cordinate drilling, but you knew that, so thanks for the demonstration. The bit about caliper flex was something I'd not fully appreciated either. How's the DeLorean build going? Bob UK.
Moving centre punch, I'm gonna try that :-)
The centre punch problem is why i dont use the ''automatic'' punches, with a hammer you can easily hit it softly first, check the location, move it of needed since it's only a miniscule dent, and then punch it bigger to get a propper centrepoint
Do you ever do a wind pass with a lathe cutter like you do with a boring bar to unload the tool?
I'm a mechanic and don't get to play with the precision tools enough, but it seems to me that a good way to practice the feel of the mic is to use the ratchet knob a few times to be sure of the dimension of the part, then start using the main knob. Repeat until you get the same measurement and start learning the feel.
One issue. With my lathe if I need to reduce the size of the part .014 I need to move the cross slide .007, not .014 as you did on yours.
Yes, that's the difference between direct-read and indirect-read hand wheels. I have a video series that covers that here:
ruclips.net/p/PLY67-4BrEae9Ad91LPRIhcLJM9fO-HJyN
The best way to clean the faces of the anvil and spindle of a 0-1" (or smaller) outside micrometer caliper, or the outside jaws of a vernier, dial, or digital caliper, is to lightly grip a piece of clean paper with them, and then pull the paper out of the instrument. Typing paper, printer paper, notebook paper... Any will do. Toilet paper? Not so much.
One important thing not mentioned about lathe work is tool pressure.
If doing several heavy cuts and one light finish cut, a change in tool pressure will make the part undersize. And yes, I have done that more than one time.
Especially with long and thin parts, it can make a large difference.
Always try to keep two finish passes same depth of cut and same feed.
Another mistake is changing a worn carbide insert and the new insert cuts better and also make the part undersize.
@Chris
But to be fair, if turning short solid brass parts with hss tools as in the video, tool pressure is mayby not so important.
When I did CNC lathe work for a living, it was mostly long 304 stainless thin and medium wall pipe, 10 to 45" long and not compensating for tool pressure would scrap most of the parts.
I was completely unaware before this video that they even made micrometers that didn't have the controlled torque ratchet! The whole time i was thinking "why is she going on about feel, just turn it till it clicks!"
When taking the multiple measurements, try to vary how you measure. take a step back from the machine, and measure from underneath if you measured from the top initially, then take a step back and then measure the end of the feature for example. The reason being, to change as much as possible surrounding the measurement, in case one of the surrounding parameters is affecting the result. perhaps when you measure across the top, you are at a slight angle, if you keep measuring across the top, you will likely repeat your error.
this philosophy goes for all checking processes, they should be as different as possible, while still verifying the core feature to be checked.
These were the mistakes of rookie machinists. Schools should have to teach how to measure, mark and machine delicate workpieces. Now after writing this, I read the description and calmed down. :)
If you're factoring primes in your head then you might want to set your sights a little higher than the machine shop floor, haha
I tend to wiggle the micrometer back and forward over the diameter so I can feel the tight spot (which is the diameter). Also I tend to have it perpendicular to the diameter and pull it off to the side. Is that bad or better? I don't know - machining is not my day job. I do think it is good feeling for the max diameter as you can miss if you aren't careful.
Freaking spell checker strikes again. Anyway I really do like your wry sense of humor . I thought you might enjoy something from my past try looking up the retroencabulator on RUclips. For the uninitiated it's fun to watch them when they finally catch on. Bet your beer is colder than mine right now.
Hey, sis. You probably need one of those optical center punch. if you want really good punching. The latest version of those punches not only build in led light source, it fit with a snake camera head which can connect to your phone. And a magnetic base, you can do punching upside down. The only problem is, it is expensive, of cause, if people is going to fix problem for you, they are going to charge. Well, you can make one in a fraction of market price too.
Well, if you want to be a “good” machinist, you’ll memorize all the tables (check the machinist’s handbook) for factoring prime numbers. I, personally, am able to factor any prime number instantly. P.S. “Quinn Dunki” is the coolest name on the planet.
Great tips Quinn, Thanks and love the channel.
for calipers i always lightly pich the jaws at the measuring point to decrease influance
So when my micro meter (which has no ratchet) has trouble letting go... I'm doing it wrong?
I'd add always wipe the part and anvils clean with a finger, not a rag because the rag could leave particles of lint. Air blow also works well to clean without the danger of adding dirt. The tensions on those ratchets can vary but that doesn't matter. The goal is to use the exact same pressure when measuring as you did when you calibrated the tool. I also agree- repeat the measurement on a different spot. On a lathe part, check both ends of the turned area to check for taper.
Zero scars on the chuck. Amazing.
I'm watching this playing "bozo bingo"
Yup, made that mistake, and that one, and that one too...bingo!
Word. I've been bodging around machine shops since high school in the 70s, I'm an experienced engineer (but not an experienced machinist) and I'm learning plenty from Quinn (and the other usual YT metal shop suspects too)