Fun With Your Gauge Blocks

I am at work and did not watch the video...

My physics professor suggested that static friction has an electron component where molecules can become polarized or at least share some electrons.

Has anyone seen the glass that can be pressed together and become inseparable without any bonding agent?

Drew K

Don't wash with water or look at them too hard kind of warnings? I can only imagine.

I had no idea these had lapped edges, but then again.. I don't have any need for them.

A buddy of mine has everything related to machining. I'll see if he flinches when I ask to see his gauge blocks.

Well, these guys were as much artisans as craftsmen and their tools were their livelihood.

They produced one-of-a-kind items for spacecraft and the military.

I learned a LOT from them, not the least of which was to respect your tools.

I always thought it was an honor that these guys would accept me as someone who could be trusted and were willing to take the time to teach me things one could never learn in school.

Exactly.

Too bad the computer this guy used to upload his video doesn't have the google app that would let him discover the name of the well known principle of which he seems blissfully unaware. Van der Waals force.

I suppose we've all noticed that microscope slides stick together...

Now, when the microscopes start sticking together, you know it's time to clean the lab.

So maybe leaving the tissue samples under the microscopes wasn't a good idea?

Yea.. It's the edge being so sticky that's the shocker. Thy that with a set of slides.

A singularly unimpressive talk.

I concur.

Also, 'fusiform' does not mean 'shaped like a cross', it means 'shaped like a spindle; wide in the middle and tapered at both ends'.

'Cruciform' means 'shaped like a cross'.

I've seen some other videos by this guy and the other videos are better. This video seems to be an outlier.

I only had enough stomach to partially view a couple other videos he posted.

More laughs than correct or usable information information.

I mean he made a threaded potato nut and bolt fried in dinosaur squeezin's for cryin' out loud.

If you skip 90% of the content it's a little easier.

Any suggestions from this fellow to save others the agony?

Hmmm. Now that I try to remember exactly what was valuable, I'm a little hard pressed. I do find him entertaining.

The dyson hairdrier teardown was satisfying, but I can't say for sure if I did or didn't skip ahead.

yeah.. that's why I thought it might be you.

..I never said it was impressive.. just a little fun.

Not Del?

Are you Del? You're sure somebody

Troll.

No, I'm not Del.

Yes, there is cohesion - whether oiled or not - due to Van der Waals's force. Clean metal in outer space (a vacuum) will instantly weld together and form a permanent bond.

Electrical contacts can stick in outer space (unless obviously engineered to be well oiled).

Consider, also, this: there is atmospheric pressure pushing on all surfaces here, so that there can be a pressure force assisting with cohesive force.

"... . Clean metal in outer space (a vacuum) will instantly weld together and form a permanent bond...."

'... Consider, also, this: there is atmospheric pressure pushing on all surfaces here, so that there can be a pressure force assisting with cohesive force..'

.

I wonder if atmospheric pressure has anything to do with wringing, especially considering clean flat surfaces don't regularly cold weld unless in a vacuum, suggesting it is the air molecules in between keeping the surfaces from joining.

The molecules of atmosphere must still be trapped between the blocks.

The minimum flatness for wring ability, is said to be ~130 nanometers. The mean free path of atmospheric constituents at STP is about half that. There should be plenty of air molecules pushing back.

On second thought, with the oil wring film, there might not be room for any atmosphere between the blocks. The surface tension, viscosity, and dilatancy of the oil wring film has to play a big part.

Wouldn't be that hard to confirm the contribution to wringing from various factors (atmospheric pressure, oil properties, etc).

Interesting point, kudos.

I worked for a lady and she said I could have everything or anything in her garage, she was going in a rest home and didn't have any living relatives. I found a set of gauge blocks.

James, I have a couple of questions:

Do they use gauge blocks to make gauge blocks or how is it done.

If clean metal is instantly welded in a vacuum, then why isn't all clean metal welded in a vacuum.

Maybe I should have said in orbit, as in outer space.

Even if the clean metal does stick together as in welded, I have no data on the quality of such welds.

How gauge blocks are made: The cutting of the blocks to size is accomplished with grinding followed by lapping. Usually no plating or other coating is involved. Blocks are kept very lightly oiled, and are stored and used in dry climate-controlled conditions; unplated, uncoated steel gauge blocks can last for decades without rusting. (source: Wikipedia)

Note that gauge blocks are standardized at 68 °F only, and must be used at that temperature. Expansion or contraction by being at different temperature will nullify the measurement.

Obviously, one must treat the blocks as if they were the family jewels, because they are.

Cold welding can be intention or not. Early satellites had some interesting failures that led investigators to believe this was the root cause.

The reason for this unexpected behavior is that when the atoms in contact are all of the same kind, there is no way for the atoms to “know” that they are in different pieces of copper. When there are other atoms, in the oxides and greases and more complicated thin surface layers of contaminants in between, the atoms “know” when they are not on the same part.

— Richard Feynman, The Feynman Lectures, 12–2 Friction (wikipedia) One source of difficulty is that cold welding does not exclude relative motion between the surfaces that are to be joined. This allows the broadly defined notions of galling, fretting, sticking, stiction and adhesion to overlap in some instances. For example, it is possible for a joint to be the result of both cold (or "vacuum") welding and galling (and/or fretting and/or impact). Galling and cold welding, therefore, are not mutually exclusive. Does that help with explanation. Thus, wringing of gauge blocks is akin to cold welding, just not brought to fruition, because there is that tiny film of "oil", or petrolatum.

To further answer your question, the flatness and thickness of gauge blocks is measured using light interferometry. The resulting flatness is truly astounding!