thanks . last week was the first time in over year i went to my shop and started back doing machine work. i had a mild stroke over a year ago and then ,reconstructive foot sugery and a hip replacement. i still have some glitches from the stroke. making parts is the best meds there are. thank you so much for your show .you are truly a master of the craft
I just bought a used one Ammco 2250 and the ratchet doesn’t make a click noise, it has a spring in there. I’m learning so I can repair my brake rotors. I think this sense of feel is personal and we never will have a perfect measure with these designs. Thanks for sharing your knowledge.
If using a standard dowel pin as a standard be aware that those pins are usually +0.0001" / +0.0002" over nominal. Pins are made this way so they will be a light drive fit into a hole that has been drilled and reamed to the nominal diameter.
Yep. That’s why I lumped them in with end mill shanks and tool bits. Dowel pins have a nice finish and they're round, but they aren't going to be right on size.
I can tell you when I was working on aircraft where everything had a specific torque (and I used a torque wrench many time a day), I had a calibrated wrist (within 5 inch-lbs) from 30-250 inch-lbs.
What is quite interesting is to do capability studies on micrometers and getting two or three people to measure the same work piece . It is best if the people are not trying to achieve a dimension and working double blind so they do not know what the other person is getting as a reading . If it is done as an honest check then the results are quite interesting . I found that the best that can be obtained with a micrometer is about .... But wait that would bias your own study 😁
Ok, Stuart, here's your repeatable method for applying torque. tape a bit of thread to the thimble and wrap around a few times, with a fish hook no the other end and use some 7th grade science class type weights to apply the torque. T = Force(weight) x distance(radius of thimble).
@@betatool-p5z I've never thought about it that way. I just go until it starts to slip or click, then I wiggle the frame of the micrometer back and forth a few times to make sure the anvils are seated on the part. That's something you can feel pretty easily. If the mic is not fully seated you'll feel it jump around a bit until it feels like it's making smooth contact with the part.
Curiously buying the best can be a hindrance. Take the mitutoyo quantum mic, good and expensive but being 2mm pitch(80 thou-ish) with umpteen decimal places on the screen and with friction thimble getting the anvil dead square is not as easy as a ratchet on a cheapo Starrett.😂
gehinarsch, I have micrometers with ratchet or friction spindles and I don't use either feature. With a bit of use you quickly develop the feel to make a good measurement. If you are working close, say +0.0001/-0.0000 then you need to check your shop micrometer against a stack of gage blocks set to the desired dimension. In that realm your micrometer may be just fine but the warmth of your hand or a fan blowing on the work can throw off the measurement.
@@aceroadholder2185 said in jest but have you seen the price of mitutoyo digital quantum mics? They are so expensive you fear using them in case you damage the paint. It took me three months to dare to not put in back in its box immediately after use, even now I have a padded tray in the head stock between measurings😉
thanks . last week was the first time in over year i went to my shop and started back doing machine work. i had a mild stroke over a year ago and then ,reconstructive foot sugery and a hip replacement. i still have some glitches from the stroke. making parts is the best meds there are. thank you so much for your show .you are truly a master of the craft
I'm glad you're back at it and feeling better. Take care!
Fabulous training video - thank you 👍👍😎👍👍
I just bought a used one Ammco 2250 and the ratchet doesn’t make a click noise, it has a spring in there. I’m learning so I can repair my brake rotors. I think this sense of feel is personal and we never will have a perfect measure with these designs. Thanks for sharing your knowledge.
Yep. That’s the friction thimble. I personally really like those. There's just a satisfying smoothness when it slips.
Very good video,Stuart.Thank you.
Thanks for this informative video. Kindly post the link for Vernier caliper and Dial gauge.
Great video. I bet a screw driver type torquewench like what's used for scope mounts might work well with an adapter and a set screw through a socket
If using a standard dowel pin as a standard be aware that those pins are usually +0.0001" / +0.0002" over nominal. Pins are made this way so they will be a light drive fit into a hole that has been drilled and reamed to the nominal diameter.
Yep. That’s why I lumped them in with end mill shanks and tool bits. Dowel pins have a nice finish and they're round, but they aren't going to be right on size.
Stuart, thanks for another great video. I'm sure that lots of your viewers are wondering about the status of your "new" machine shop.
I'm working on another update right now as a matter of fact. Stay tuned.
I can tell you when I was working on aircraft where everything had a specific torque (and I used a torque wrench many time a day), I had a calibrated wrist (within 5 inch-lbs) from 30-250 inch-lbs.
That's the companion to the Mark I Eyeball, right?
@@StuartdeHaro roger that.
What is quite interesting is to do capability studies on micrometers and getting two or three people to measure the same work piece . It is best if the people are not trying to achieve a dimension and working double blind so they do not know what the other person is getting as a reading . If it is done as an honest check then the results are quite interesting .
I found that the best that can be obtained with a micrometer is about ....
But wait that would bias your own study 😁
Just as with torque values, I tighten until the threads strip and then back off 1/4 turn. That’s about the right spot.
Exactly right
Ok, Stuart, here's your repeatable method for applying torque. tape a bit of thread to the thimble and wrap around a few times, with a fish hook no the other end and use some 7th grade science class type weights to apply the torque. T = Force(weight) x distance(radius of thimble).
I knew I could rely on you, Randy!
I tapped the like button with a force of 1.44(0.73)N.
Thanks for the existential crisis after I had to slow the video down to .25 to see what you’d put in the caption
Now I have to rewatch it to see what I wrote.
Edit: Yeah, sorry about that. That got a little dark. But hey, thanks for watching!
U didn't mention exactly how many sounds or turns should it be in modern micrometers?
@@betatool-p5z I've never thought about it that way. I just go until it starts to slip or click, then I wiggle the frame of the micrometer back and forth a few times to make sure the anvils are seated on the part. That's something you can feel pretty easily. If the mic is not fully seated you'll feel it jump around a bit until it feels like it's making smooth contact with the part.
Solution to the problem, don't be cheap and buy a micrometer with a ratched, end of story
Curiously buying the best can be a hindrance. Take the mitutoyo quantum mic, good and expensive but being 2mm pitch(80 thou-ish) with umpteen decimal places on the screen and with friction thimble getting the anvil dead square is not as easy as a ratchet on a cheapo Starrett.😂
@@chrisstephens6673 I have to admit that is the first time I have ever seen "Starrett' and "cheap" used in the same sentence.
gehinarsch, I have micrometers with ratchet or friction spindles and I don't use either feature. With a bit of use you quickly develop the feel to make a good measurement. If you are working close, say +0.0001/-0.0000 then you need to check your shop micrometer against a stack of gage blocks set to the desired dimension. In that realm your micrometer may be just fine but the warmth of your hand or a fan blowing on the work can throw off the measurement.
@@aceroadholder2185 said in jest but have you seen the price of mitutoyo digital quantum mics? They are so expensive you fear using them in case you damage the paint. It took me three months to dare to not put in back in its box immediately after use, even now I have a padded tray in the head stock between measurings😉