What can I do with these rulers?

The Rocketry Forum

Help Support The Rocketry Forum:

lakeroadster

👀 Oddroc Scum 👀 CAD Monkey Swingkinder
Joined
Mar 3, 2018
Messages
4,709
Reaction score
4,221
Location
Central Colorado
That's a ... rather loaded way to ask the question.
We're all adults here. And, kudo's to @MetricRocketeer for answering the question.

With all the craziness going on in the educational system today, there shouldn't be any questions that shouldn't be asked. Keep in mind, @MetricRocketeer had up to this time only stated he was a teacher, I assumed public schools, he later disclosed it was for a university.

I have friends that live in Fort Collins Colorado who recently moved to Nebraska.. partly because of this "art program".
 

boatgeek

Well-Known Member
Joined
Dec 27, 2014
Messages
4,646
Reaction score
3,708
We're all adults here. And, kudo's to @MetricRocketeer for answering the question.

With all the craziness going on in the educational system today, there shouldn't be any questions that shouldn't be asked. Keep in mind, @MetricRocketeer had up to this time only stated he was a teacher, I assumed public schools, he later disclosed it was for a university.

I have friends that live in Fort Collins Colorado who recently moved to Nebraska.. partly because of this "art program".
I’m just saying that however strongly you feel about imperial units, “grooming” is a completely inappropriate word choice. Teaching metric /= pedophilia and it never has. Also, the assumption that the metric system wouldn’t be in a K-12 math curriculum is kind of weird. Any student needs to have some familiarity with the metric system to do any work in the hard sciences, particularly chemistry. Getting students familiar with metric before they have to use it helps them move directly into those subjects without a lag.
Anyway, back to discussion of rulers.
 

lakeroadster

👀 Oddroc Scum 👀 CAD Monkey Swingkinder
Joined
Mar 3, 2018
Messages
4,709
Reaction score
4,221
Location
Central Colorado
I’m just saying that however strongly you feel about imperial units, “grooming” is a completely inappropriate word choice. Teaching metric /= pedophilia and it never has. Also, the assumption that the metric system wouldn’t be in a K-12 math curriculum is kind of weird. Any student needs to have some familiarity with the metric system to do any work in the hard sciences, particularly chemistry. Getting students familiar with metric before they have to use it helps them move directly into those subjects without a lag.
Anyway, back to discussion of rulers.
You teach the curriculum... that you have been instructed to teach.

Also, don't let those sons-a-bitches redefine on their terms, what has already been defined by a rational society.

Grooming

noun​

  1. Preparing a person for a position requiring skilled behavior, especially by providing opportunity for practice and guidance in making the right decisions.
  2. The activity of getting dressed, washed and generally of neat appearance.
  3. The activity of cleaning oneself or others by removing lice, ticks, dirt, etc. from the fur; -- of animals.
 
Last edited:

boatgeek

Well-Known Member
Joined
Dec 27, 2014
Messages
4,646
Reaction score
3,708
You teach the curriculum... that you have been instructed to teach.
Average and subpar teachers stick slavishly to the curriculum. Good teachers bring in more material than the curriculum covers to help explain the curriculum to the students. Great teachers give their students a love of the subject.

A small example: in high school, my freshman science class was invited into the junior chemistry class for a demonstration of gas combustion. the chem teacher had filled three balloons with helium, hydrogen, and a stoichiometric mixture of hydrogen and oxygen. The teacher then popped each balloon using a lit candle on the end of a stick, with increasingly dramatic results. Was this in the curriculum or any state test? Not at all. Did it give the students a real appreciation for combustion? Absolutely! The teacher was fired by the administration by the end of the year for not adequately toeing the line. That was a loss for the science department as a whole.

Also, don't let those sons-a-bitches redefine on their terms, what has already been defined by a rational society.

Grooming

noun​

  1. Preparing a person for a position requiring skilled behavior, especially by providing opportunity for practice and guidance in making the right decisions.
  2. The activity of getting dressed, washed and generally of neat appearance.
  3. The activity of cleaning oneself or others by removing lice, ticks, dirt, etc. from the fur; -- of animals.
Oh please. The Venn diagram of [people saying that teachers should just teach the curriculum and closely limiting that curriculum] and [people describing teachers as groomers, absolutely 100% meaning pedophiles] is a single circle. The "SOBs redefining on their terms" are the people who you agree with.

Anyway, I've threadjacked this enough. That's my last word on the subject in this thread.
 

Funkworks

Low Earth Orbit, obstructing Earth's view of Venus
Joined
Jul 28, 2018
Messages
3,269
Reaction score
3,350
One part of my job is using a ruler to measure to 0.01"* in the field. I find it a little easier to use a ruler graduated every 0.02" since it's easier to distinguish the markings and take odd hundredths when the drawn line lands between the marks. We do have a scale that's graduated in 0.01" with large marks every 0.05"; medium marks at 0.02", 0.03", 0.07", and 0.08"; and small marks in between. That's OK, and far easier to read than marks at straight 0.01" increments.

* In reality, our precision is probably in the range of 0.02"-0.03", but recording to 0.01" makes our lives somewhat easier.

I've gotten to the point where I use my dial calipers more than I do the Engineer's scale.
Yes, developping vernier scales and digital calipers were much smarter ideas than simply making the markings thinner. I guess an issue with those is they're only available up to a 15-cm length. I think longer one do exist but they're very expensive.

In case anyone else was wondering, I looked up this morning why Cesium (among other atoms) was chosen to define the second, and it's because it has a lone electron in its outer shell. Because that lone electron is minimally affected by all the other electrons of a Cesium atom, its transition from spin up to spin down (were it in a magnetic field) emits a photon with minimal uncertainty. Minimal uncertainty - that's what we want from a time standard. Out of all atomic transitions, that lone atomic electron transitionning from spin up to spin down, is the one emitting a photon with a wavelength (or period, or frequency) having minimal uncertainty.

Here's that lone electron in the outer shell on top of his game. The Michael Jordan of time keeping.

C0456399-Caesium,_atomic_structure.jpg

So my point is that this little guy is what all other time units are based on, and when you add the speed of light constant (speed of an electro-magnetic wave in vacuum, to be precise) to the soup, you get definitions for all length measurements (which is what this thread is about).

Average and subpar teachers stick slavishly to the curriculum. Good teachers bring in more material than the curriculum covers to help explain the curriculum to the students. Great teachers give their students a love of the subject.
I have both "brought more material than the curriculum", and criticized teachers for bringing too much more material (curiously, I explained how anthropogenic climate change can be demonstrated with radioactivity, and I criticized a professor for being too "green" 😆).
 

lakeroadster

👀 Oddroc Scum 👀 CAD Monkey Swingkinder
Joined
Mar 3, 2018
Messages
4,709
Reaction score
4,221
Location
Central Colorado
Yes, developping vernier scales and digital calipers were much smarter ideas than simply making the markings thinner. I guess an issue with those is they're only available up to a 15-cm length. I think longer one do exist but they're very expensive.

In case anyone else was wondering, I looked up this morning why Cesium (among other atoms) was chosen to define the second, and it's because it has a lone electron in its outer shell. Because that lone electron is minimally affected by all the other electrons of a Cesium atom, its transition from spin up to spin down (were it in a magnetic field) emits a photon with minimal uncertainty. Minimal uncertainty - that's what we want from a time standard. Out of all atomic transitions, that lone atomic electron transitionning from spin up to spin down, is the one emitting a photon with a wavelength (or period, or frequency) having minimal uncertainty.

Here's that lone electron in the outer shell on top of his game. The Michael Jordan of time keeping.

View attachment 519650

So my point is that this little guy is what all other time units are based on, and when you add the speed of light constant (speed of an electro-magnetic wave in vacuum, to be precise) to the soup, you get definitions for all length measurements (which is what this thread is about).


I have both "brought more material than the curriculum", and criticized teachers for bringing too much more material (curiously, I explained how anthropogenic climate change can be demonstrated with radioactivity, and I criticized a professor for being too "green" 😆).

Absolute Digital Caliper 12” / 300 mm Digital Calipers Accurate to 0.0015”/12” Hardened Stainless Steel ODC-12 $35.99

 

Blast it Tom!

Well-Known Dweeb
Joined
Dec 29, 2019
Messages
1,648
Reaction score
1,386
Location
Pittsburgh
Last edited:

lakeroadster

👀 Oddroc Scum 👀 CAD Monkey Swingkinder
Joined
Mar 3, 2018
Messages
4,709
Reaction score
4,221
Location
Central Colorado
I just refreshed a 12" Starrett vernier inside/outside caliper (no. 122) that I picked up at a flea market for $20. If was frozen, but soaking it in penetrating oil and sole judicious gentle tapping (padded with wood) brought it back into full operation.
And a Starrett is a true quality tool. Well played.
 

Grant_Edwards

Well-Known Member
Joined
Jul 21, 2020
Messages
334
Reaction score
292
Location
Minneapolis
In case anyone else was wondering, I looked up this morning why Cesium (among other atoms) was chosen to define the second, and it's because it has a lone electron in its outer shell. Because that lone electron is minimally affected by all the other electrons of a Cesium atom, its transition from spin up to spin down (were it in a magnetic field) emits a photon with minimal uncertainty. Minimal uncertainty - that's what we want from a time standard. Out of all atomic transitions, that lone atomic electron transitioning from spin up to spin down, is the one emitting a photon with a wavelength (or period, or frequency) having minimal uncertainty.

There are atoms with higher frequency (smaller wavelength) transition energies which are proving to be more accurate than the Cesium transition currently used as the standard — more accurate by a couple orders of magnitude. These frequencies are in the range of visible light, so they're usually referred to as "optical" atomic clocks. There is talk of switching to one of those instead of Cesium as the standard, but that's probably years away:

https://jila.colorado.edu/news-even...locks-record-accuracy-over-both-fiber-and-air
https://www.nature.com/articles/s41586-021-03253-4
 

teepot

Well-Known Member
Joined
Dec 7, 2019
Messages
2,689
Reaction score
2,446
Location
Pahrump, Nevada
When we lived in England, some golf courses were measured in yards and some in meters. I could do those rough calculations in my head. Anyone that has been in the military should be able use both metric and imperial. That's how I learned to use both. I have a digital caliper that helps me switch back and forth between the two. But I'm still old school. A scale, triangles and a T square. If I had more room I would get a drafting table. I took mechanical drawing and drafting in high school. Which was about 50 years ago. Yikes.
 

hobie1dog

Subaholic
Joined
Jul 25, 2009
Messages
8,466
Reaction score
5,165
Location
Cornelius,NC
But I'm still old school. A scale, triangles and a T square. If I had more room I would get a drafting table. I took mechanical drawing and drafting in high school. Which was about 50 years ago. Yikes.
I loved drafting but never scored well in the classes. :( I still have my drafting tool set from 1975. I used my triangular ruler today to draw a straight line and to measure how far a forward set of fins are going to be.
 

lakeroadster

👀 Oddroc Scum 👀 CAD Monkey Swingkinder
Joined
Mar 3, 2018
Messages
4,709
Reaction score
4,221
Location
Central Colorado
When we lived in England, some golf courses were measured in yards and some in meters. I could do those rough calculations in my head. Anyone that has been in the military should be able use both metric and imperial. That's how I learned to use both. I have a digital caliper that helps me switch back and forth between the two. But I'm still old school. A scale, triangles and a T square. If I had more room I would get a drafting table. I took mechanical drawing and drafting in high school. Which was about 50 years ago. Yikes.
I loved drafting but never scored well in the classes. :( I still have my drafting tool set from 1975. I used my triangular ruler today to draw a straight line and to measure how far a forward set of fins are going to be.

My High School drafting teacher created a "Senior" drafting class so I could take another year of drafting. A true pivotal person in my life. I still have the drawings, a T-Square and a "Boardmaster" parallel-o-gram drafting machine.
 

rharshberger

Well-Known Member
Joined
Oct 13, 2014
Messages
11,092
Reaction score
2,980
Location
Pasco, WA
My High School drafting teacher created a "Senior" drafting class so I could take another year of drafting. A true pivotal person in my life. I still have the drawings, a T-Square and a "Boardmaster" parallel-o-gram drafting machine.
In high school and college we used mainly the Vemco Drafting Machines (occasionally an Alvin style too) which are similar to the Boardmaster machines, but on several occasions I did use a parallel edge type system.
 

lakeroadster

👀 Oddroc Scum 👀 CAD Monkey Swingkinder
Joined
Mar 3, 2018
Messages
4,709
Reaction score
4,221
Location
Central Colorado
In high school and college we used mainly the Vemco Drafting Machines (occasionally an Alvin style too) which are similar to the Boardmaster machines, but on several occasions I did use a parallel edge type system.

I started out using stone pillars, a hammer and chisel.
Ended my career on a CAD station.

The middle part is kind of a blur

1982 - Chemineer Family Picnic.jpg
 

Pem Tech

Well-Known Member
Joined
Jan 19, 2009
Messages
4,685
Reaction score
303
Location
Llama Central
I have a Staedtler 987 19-1 “metric” ruler, a Staedtler-Mars 987 18-31 “architect” ruler, and a number 240BP “architect” ruler. See pic. Got these at thrift store for less than a dollar (US) each.

I figured there has to be a model rocket use for these fancy rulers.

Any suggestions?

View attachment 519096

Nice socks...
 

rharshberger

Well-Known Member
Joined
Oct 13, 2014
Messages
11,092
Reaction score
2,980
Location
Pasco, WA
I started out using stone pillars, a hammer and chisel.
Ended my career on a CAD station.

The middle part is kind of a blur

View attachment 520148
Yeah, I started my freshman year of H.S. using drafting machines, and ocassionally getting to play with AutoCad (the very first version Mk1ModO) using a sensor pad with pen (drawing a blank on what that pad was actually called) on a Apple IIe "Enhanced" computer iirc. Oh yeah the pad was a digitizer pen and pad...getting older sucks...

Still have and often use my Staedtler, Koh-i-nor, and various other brands of manual drafting tools, only now its with a board and T square.
 

lakeroadster

👀 Oddroc Scum 👀 CAD Monkey Swingkinder
Joined
Mar 3, 2018
Messages
4,709
Reaction score
4,221
Location
Central Colorado
Yeah, I started my freshman year of H.S. using drafting machines, and ocassionally getting to play with AutoCad (the very first version Mk1ModO) using a sensor pad with pen (drawing a blank on what that pad was actually called) on a Apple IIe "Enhanced" computer iirc. Oh yeah the pad was a digitizer pen and pad...getting older sucks...

Still have and often use my Staedtler, Koh-i-nor, and various other brands of manual drafting tools, only now its with a board and T square.
Ah yes, ye old Digitizer Pen & Pad.. pre-drop down windows days. I remember programming those to allow input of commands, which greatly increased productivity over typing in commands. I was through college and working my 2nd job before I finally landed a job where I could use CAD.
 

bjphoenix

Well-Known Member
Joined
May 3, 2011
Messages
1,092
Reaction score
259
My High School drafting teacher
None of that stuff in my high school, we had to take too much history, english, etc. I took one small drafting class in college. In business we had dedicated draftsmen that drew pen and ink on mylar, then we got into autocad and I did a lot of my own drafting after that. These days autocad is gone and we do everything in Revit.
This afternoon I was working in autocad to draw up a design I want to kit bash a baby bertha into.
 

lakeroadster

👀 Oddroc Scum 👀 CAD Monkey Swingkinder
Joined
Mar 3, 2018
Messages
4,709
Reaction score
4,221
Location
Central Colorado
None of that stuff in my high school, we had to take too much history, english, etc. I took one small drafting class in college. In business we had dedicated draftsmen that drew pen and ink on mylar, then we got into autocad and I did a lot of my own drafting after that. These days autocad is gone and we do everything in Revit.
This afternoon I was working in autocad to draw up a design I want to kit bash a baby bertha into.

Autocad is by no means "gone".

Autodesk makes Revit and Autocad. Both useful items, geared toward different uses. Understanding the differences between BIM and CAD

As to pen and ink on mylar, I did that back in the 1980's. Incredibly tedious. Now that is pretty much gone, being replaced by "printers".
 

Blast it Tom!

Well-Known Dweeb
Joined
Dec 29, 2019
Messages
1,648
Reaction score
1,386
Location
Pittsburgh
Autocad is by no means "gone".

Autodesk makes Revit and Autocad. Both useful items, geared toward different uses. Understanding the differences between BIM and CAD

As to pen and ink on mylar, I did that back in the 1980's. Incredibly tedious. Now that is pretty much gone, being replaced by "printers".
You know, I also used AutoCad 'way back in the 80's and onward, and thought the associative dimensions were just grand. But when we started using Solidworks, I thought immediately, "This is how it's done!" In SW, the dimension drives the size of the entity, not the entity driving the value of the associative dimension. So for modeling, it's grand. I think the translation back to a working drawing leaves something to be desired, but our drafters seem to do okay with it. Probably a lack of familiarity on my part.

So if that isn't clear, in AutoCad you draw a line or circle and give it a length of diameter. Then when you dimension it, the dimension picks up the size from the line or circle and places it as text. In Solidworks (and probably others), when you draw the line or circle, the dimension is added and, when you fill in the dimension text, the line, circle, etc is sized to the value that you input, and can be changed by editing the dimension text directly.

But I still keep some drafting tools on hand, and several slide rules, as well. I even have a working slide rule on my computer! I always pranked the young engineers with it!
 
Last edited:

lakeroadster

👀 Oddroc Scum 👀 CAD Monkey Swingkinder
Joined
Mar 3, 2018
Messages
4,709
Reaction score
4,221
Location
Central Colorado
You know, I also used AutoCad 'way back in the 80's and onward, and thought the associative dimensions were just grand. But when we started using Solidworks, I thought immediately, "This is how it's done!" In SW, the dimension drives the size of the entity, not the entity driving the value of the associative dimension. So for modeling, it's grand. I think the translation back to a working drawing leaves something to be desired, but our drafters seem to do okay with it. Probably a lack of familiarity on my part.

So if that isn't clear, in AutoCad you draw a line or cirlcle and give it a length of diameter. Then when you dimension it, the dimension picks up the size from the line or circle and places it as text. In Solidworks (and probably others), when you draw the line or circle, the dimension is added and, when you fill in the dimension text, the line, cirlce, etc is sized to the value that you input, and can be changed by editing the dimension text directly.

But I still keep some drafting tools on hand, and several slide rules, as well. I even have a working slide rule on my computer! I always pranked the young engineers with it!

Solidworks and Autodesk Inventor are basically the same horse. I had those "revelation" moments, when I upgraded from AutoCad to Inventor. Basically upgrading to a Solid Modeling format.

I used Solidworks for a 2 year span doing design and engineering for a cryogenics company.
 

Blast it Tom!

Well-Known Dweeb
Joined
Dec 29, 2019
Messages
1,648
Reaction score
1,386
Location
Pittsburgh
Solidworks and Autodesk Inventor are basically the same horse. I had those "revelation" moments, when I upgraded from AutoCad to Inventor. Basically upgrading to a Solid Modeling format.

I used Solidworks for a 2 year span doing design and engineering for a cryogenics company.
No, I haven't used Inventor, but as you said, they are about the same. I'm not sure what I'll do when I no longer have access to the company software, but as a semi-retired consultant I still get to use ANSYS, Solidworks, Mathcad, etc. - when I have the time, which in the spring isn't very often.

Working for a cryogenics company must've been really (wait for it....) cool! duck.gif
 

bjphoenix

Well-Known Member
Joined
May 3, 2011
Messages
1,092
Reaction score
259
Autocad is by no means "gone".
What I meant was it is no longer used where I work. Well I still use it when I need to create drawings of my own. Things like solid works and inventor and revit are more about modeling complicated entities, autocad is more an electronic form of drafting. Our technicians spend a lot of time fighting with Revit to make it do what they want, and when I see linework on drawings that isn't correct they just say that Revit can't do any better. In autocad I can make it look exactly like it should be. I've tried to point out to them that for some tasks they could finish them much faster in autocad but they don't want to have to maintain 2 different sets of programs and standards.
I'm working on a kit bash that involves multiple overlapping tubes. I've been working out the geometry in autocad, I'm ready to start slicing up tubes now.
 

Sandy H.

Well-Known Member
Joined
Mar 20, 2009
Messages
1,686
Reaction score
1,067
I need to fnd old PC with a 5.25” drive so I can archive my DOS shareware from the early 90’s. Also, I need a way to rescue my beloved “Empire: Wargame of the Century” files that are only those old 5.25” floppies from 1991.

Apparently there are a few companies making a USB to 5.25" adapter. Archive your stuff, create a VM with on old OS and go back down memory lane!!!

Sandy.
 
Top