Recent comments in /f/BuyItForLife

Lampshader t1_j93cof0 wrote

Reply to comment by A_Light_Spark in "The longest-lived micrometer than can be bought." J.T. Slocomb micrometers and stand, all fully restored by myself. Each mic is between 70-120 years old, and they're all still accurate. by ExHempKnight

>- have no moving mechanism

Uh, have you used a micrometer before? They have moving parts, that's kinda their defining feature, the use of a threaded mechanism to get higher precision

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Lampshader t1_j93bwfk wrote

Reply to comment by shadowsong42 in "The longest-lived micrometer than can be bought." J.T. Slocomb micrometers and stand, all fully restored by myself. Each mic is between 70-120 years old, and they're all still accurate. by ExHempKnight

If you use English spelling, the terms are distinct:

Micrometre: one millionth of a metre

Micrometer: tool to accurately measure small distances

Americans spell the unit of measurement as "meter" though, presumably as part of their quest to sabotage the metric system (or should that be meteric system?)

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Teutonic-Tonic t1_j93akww wrote

Reply to comment by slymomma in I have two low pile/almost no pile area rugs and hardwood floors. I’m tired of vacuum cleaners that just stop working after a couple years. I do have pets. Anyone have any experience with carpet sweepers? And can you recommend a bifl one? by 1212gatez

Had a canister version long ago. Kept it going for 6 or 7 years but it had a heavy amount of plastic and fiberglass repair epoxy on it by the end. Have a V6 cordless handheld now and it works well, but battery didn’t last a year and the plastic canister broke the first week. They just use a very brittle plastic compared to my Miele. Dyson is also constantly changing their over complicated designs while Miele has a tried and true simple clamshell that has been refined for generations.

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ExHempKnight OP t1_j93adnm wrote

Reply to comment by agnarxrist in "The longest-lived micrometer than can be bought." J.T. Slocomb micrometers and stand, all fully restored by myself. Each mic is between 70-120 years old, and they're all still accurate. by ExHempKnight

Everything is flexible, to some degree. Drop a feather onto a pool table, and the weight of that feather will bend the slate of the pool table. It's a tiny, tiny, TINY amount, but given appropriately sensitive equipment, you will find that there's a deflection.

When you're measuring down to 3, 4, or especially 5 decimal places, even the heat of your breath can distort a part a measureable amount.

Robin Renzetti has a great demonstration of this, if you're curious. Skip to 31:00 for the relevant part.

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ExHempKnight OP t1_j9393g3 wrote

Reply to comment by HipsterGalt in "The longest-lived micrometer than can be bought." J.T. Slocomb micrometers and stand, all fully restored by myself. Each mic is between 70-120 years old, and they're all still accurate. by ExHempKnight

They're honestly not hard to restore... Disassemble, clean, strip paint, re-enamel the engravings, mask, paint, reassemble with a drop of appropriate oil, calibrate. Just takes patience and attention to detail.

There's probably around $500 in all this. Plus a couple hundred of hours of my own work.

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ExHempKnight OP t1_j938bao wrote

Reply to comment by thewander in "The longest-lived micrometer than can be bought." J.T. Slocomb micrometers and stand, all fully restored by myself. Each mic is between 70-120 years old, and they're all still accurate. by ExHempKnight

Been into machining a long time. Subscribed to a couple dozen different machining channels.

Check out Clickspring. His clock-making series is amazing, even if you're not into machining.

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ExHempKnight OP t1_j9384jw wrote

Reply to comment by [deleted] in "The longest-lived micrometer than can be bought." J.T. Slocomb micrometers and stand, all fully restored by myself. Each mic is between 70-120 years old, and they're all still accurate. by ExHempKnight

Lol relax! This is my basement shop. The walls don't need to be pretty.

As for the granite... That's the most important thing in my shop. It's called a surface plate, and it's flat. Very, very flat. The difference between the highest and lowest points, over the entire 12"x18" surface, is less than 0.0002".

A surface plate is the reference for the entire shop. Using various instruments, I can use the plate to tell if a part I made is flat, if opposite faces are parallel, or if perpendicular faces are, in fact, perfectly square. I can measure the height of objects relative to one another. I can use it to make other things flat, and then use those things to check the flatness of other things, such as the sliding surfaces between different moving parts of a machine.

Mine is a relatively small surface plate. They can get downright huge. 10, 20 feet long, and 1-2 feet thick. And bigger.

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ExHempKnight OP t1_j936wep wrote

Reply to comment by TheMooJuice in "The longest-lived micrometer than can be bought." J.T. Slocomb micrometers and stand, all fully restored by myself. Each mic is between 70-120 years old, and they're all still accurate. by ExHempKnight

Mostly, measuring instruments like this are used in precision machining. Metalworking lathes, milling machines... Stuff like that. I have a small hobby shop in my basement with a lathe, a mill, and a couple of other machines.

Machining in and of itself is a big part of my hobby, but it also supports basically all the other things I'm interested in. I've designed and machined a custom hotend for my 3d printer. I've machined mounts and pulleys to mount a supercharger on my mid-90s Saturn. Brackets for valves on my beer brewing rig. Custom feet for my bed, which house scales, which I use to tell my home automation system when I'm in bed. I could go on.

As for the thread wear compensation... I'll preface this by saying that Starrett and Mitutoyo are fine instruments, have been around for a long time, and are basically industry standard as far as I know. Thread wear in a micrometer is not a huge issue, and plenty of those mics are still kicking, and still accurate, with decades on the clock.

So, quick and dirty micrometer terminology:

  • Thimble: the part you actually turn with your fingers.
  • Spindle: rod that sticks out of the of the thimble. Has external threads on the end inside the thimble, the other end is a very flat face, which is one half of the measuring surfaces
  • Barrel: cylindrical part of the micrometer frame, has internal threads that the spindle screws into
  • Frame: the main body of the instrument.
  • Anvil: sits in the frame, directly opposite the spindle. This is the other half of the flad measuring surfaces.

Starrett and Mitutoyo compensate for thread wear using a tapered, threaded collar at the far end of the barrel. There's slits in the end where the anvil screws in, and the tapered thread is on the outside. As you tighten the collar, it squeezes those slits smaller, which tightens the internal threads.

The problem with that, is it's only those first couple of threads that are taking up the slack.

The Slocomb micrometers use a 2-piece threaded portion. The 2 pieces have serrations that mesh. If the thread wears, you simply tighten the outer collar one or two serrations, and all the slack is gone. The difference here is that by clocking the threads differently, it causes all the threads to be engaged, rather than just a few at the very end.

This distributes the wear over more surface area, which will make it wear slower. Plus, you can clock the threads infinitely, whereas you can only tighten a tapered collar so much.

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mnistor1 t1_j9359eu wrote

Reply to If you shave, get a shaving handle that uses a simple disposable razor. The razor lasts much longer than anything at your local store and provides a better shave. by bi_polar2bear

I have a love hate with double edge safety razors. I bought a Merkur futur several years ago and go through phases of using that or a typical multi blade razor. The futur is awesome but I cut myself every single shave whereas the multi blade razor I can shave at least twice as fast with 0 cuts so I often stop using the futur because besides feeling awesome and cool, why would I choose to suffer? I may just have to adjust it down to “1” which is the least exposed adjustment and see if I have any better luck because I love it as an item but ultimately it feels like a net loser for the sake of “being cool”.

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