how do you read a ruler?

[gunsmith]

I bluffed my way into a job that uses a tape measure, what I use to do was
just say to my self is it's (say) 3ft and three little lines.

I need this job so is there any tutorials or contracters that can tell me ?

[Ron]

Count the lines on the ruler inside one inch.

There are 16 lines = 16ths of an inch

There are 8 lines larger or taller than the little lines = 1/8ths of an inch

There are 4 lines even larger yet = 1/4 of an inch

The biggest line in the middle is half an inch



What you may need is a refresher on fractions. You will never see something like 6/16 in a measurement because it is really 3/8. If you don't understand why then the fractions refresher is what you need.

[Car Knocker]

Until you get the analog version figured out, hie thee down to Target and get a digital tape measure: http://www.target.com/gp/detail.html?_encoding=UTF8&frombrowse=1&asin=B00002254Y

[Art Eatman]

fistful, you'd be amazed.  My wife's little manufacturing business (wooden boxes for tole painters) basically had only one needed qualification for employment:  Read the fractions on a ruler.  A notable percentage of people couldn't.  That included students at the local Tech College.

I guess I was lucky, paddling around under my grandfather's feet when I was maybe six or so as he would do carpentry work.  I'd mess with his six-foot folding ruler and he'd explain the fractions.


Hey, gunsmith:  Count the lines which subdivide an inch.  Sixteen of them?  Okay, one line = one-sixteenth.  Two lines = two-sixteenths or one-eighth, or 1/8.  Just divide the top number (2) into both itself and into the bottom number (16).  Four lines = four-sixteenths or one-quarter, or 1/4.  If the measurement calls for a half-inch, that's 1/2 or eight of the lines.  You'll need to know the odd-numbered stuff; it's easy:  For instance, 3/8, times two is 6/16, or six lines.

Write it down and carry the "cheat-sheet" with you.  You'll learn.

Art

[brimic]

Bonus question for the experts:  What are the black diamonds that are located at roughly 19 3/16" and multiples of that number on a tapemeasure used for?
(its not quite 19 3/16, but closer to 19 7/32")  I haven't been able to figure out what they are for.

[The Rabbi]

Bonus question for the experts:  What are the black diamonds that are located at roughly 19 3/16" and multiples of that number on a tapemeasure used for?
(its not quite 19 3/16, but closer to 19 7/32")  I haven't been able to figure out what they are for.

I believe those are the studs in the wall.  That is about the standard distance between studs.

[Perd Hapley]

Unless things have changed recently, studs are usually on 16" centers.  The distance between outside edges would be 16" plus the depth of the stud - about 17.5, 17.75.  So, that doesn't seem to explain the 19 and 3/8

[mfree]

It does explain it; 19.2" centers let you cut one stud per 8'. 96/16=6 studs, 96/19.2=5 studs. Going to four would be 24" centers and that's not enough support.

[TarpleyG]

You need a tape measure with a blade like this...I don't care for it but it will work for folks that have a hard time with it.

http://www.asktooltalk.com/home/qanda/faq/tools/tapemeasure.htm



Oh, and the black diamonds are explained at the same site...

The black diamond on the top scale starting at 19.2 inches is for truss layouts for 8-foot sheet goodsalso referred to as the "black truss" markings. Originally the 19.2 was used in metric layouts. If you divide five into 96 inches (8 feet), it will give 19.2 inchesin other words, 5 trusses per sheet.

Greg

[Ben]

Pretty much everyone I work with has a Masters Degree or higher (most of them in administration, environmental science, or biology). I can guarantee you fully 50% of them would not be able to read a tape measure. I have emperical evidence for two of them. Of the 50%, most all of them would be early 30's or younger. Not a dig at younger people, but something must have changed in public education since I (46) went to school. I still remember fractions took up a considerable portion of mathematics in Grade School.

[Nathaniel Firethorn]

And heaven help 'em if they ever had to read a vernier scale.

- NF

[HankB]

And heaven help 'em if they ever had to read a vernier scale.

Funny you should bring this up.

Back in my high school days, I worked after school and weekends as a shipping clerk at a small manufacturing plant. One day "Rich", one of the "engineers" from the front office, fresh out of college, showed up in the warehouse with a clipboard and calipers to measure the thickness of some of the metal our product was made out of. I was asked to help him locate the items and pull them out of inventory in the warehouse

So I did . . . and it was almost funny to see the expression on his face when he opened up the caliper case and saw it wasn't a dial, but a vernier caliper.

I asked if there was a problem . . . he said "Well, Joe gave me these, and I don't know how to read a vernier . . . I'll have to go get a set of dial calipers."

I said "Here, no problem" and took the calipers out of his hands and proceeded to take the measurements, explaining the use of the vernier as I went along.

SO he got his measurements, and went back up front. He told "Joe" that next time he wanted a set of dial calipers, as it was pretty embarassing to have some young high school kid in the shipping department show him how to do his job. And the kid rubbed it in by saying his Dad taught him how to read calipers when he was "just a little kid" in grammar school.

Other guys started laughing . . . and asked him what the clerk looked like. (He described me.) This set off more hoots and hollers. "Sounds like Joe's son bailed you out!"

Yep. :grin:

[Laurent du Var]

Gunsmith, move to Europe,

10 mm = 1 cm,
100 cm = 1 m,
1000 m = 1km.
Voila.

 How you guys ever get to build doors that would fit into the doorframes is beyond   me...

[Tallpine]

I am astounded ... I opened this thread thinking it must be a joke ("Queen Elizabeth was also a ruler..." )

I don't ever remember learning how to read a ruler.  Maybe I was born knowing how...?

I thought it was something that everybody (at least every man and boy;) ) knew how to do.

Just like lining up the sights on a gun ... I don't think anybody ever taught me that.  I just seemed to figure it out or it was totally obvious

Or maybe a previous life ................  

[client32]

Wow, the things you don't realize you know.  I grew up doing carpentry work.

Someone mis-diagnosed the black diamonds as stud markings.  Stud are typically 16" or 24" apart.  Most tape measures will have the multiples of 16" marked in red for finding the 16" centers easier.

[JonnyB]

Wow, the things you don't realize you know.  I grew up doing carpentry work.

Someone mis-diagnosed the black diamonds as stud markings.  Stud are typically 16" or 24" apart.  Most tape measures will have the multiples of 16" marked in red for finding the 16" centers easier.

The black diamonds aren't for studs, typically (though you could use 'em that way, I guess). They're for floor joists on 19.2" centers. Two by 10 or two by twelve joists are on 12 or 16 inch centers but the wood "I-beam" joists can be spaced wider, as they're stronger than two-bys. The truss joists, made up of bridged 2 x 4s can be spaced at 24 inches and still provide enough support.

I, too, am stunned that there are those among us ignorant of these things. I thought *everyone* could read rules, tapes and vernier scales.

jb

[Perd Hapley]

Never heard of a vernier, but then I've also forgotten how to read a slide rule and most of the calculus I learned about 10-12 years ago.

Laurent, it takes a special kind of intelligence to use English measurements.  That's why Anglophones run the world.  

[CAnnoneer]

Go Metric!

[The Rabbi]

Laurent, it takes a special kind of intelligence to use English measurements.  That's why Anglophones run the world.  

+one baker's dozen!

[Art Eatman]

Messin' with cars makes shifting back and forth from metric to SAE real easy.  But the the Engllish dreamed up Whitworth nuts and bolts--which even a Cresccent wrench won't fit.

Art

[Nightfall]

Go Metric!

Agreed. If you have to do any mathematical work with your measurements, metric makes life just a bit easier...

[esheato]

This is why APS is great...

I didn't even know what a vernier caliper was. Now I not only know what it is...but I know how to read one.

Ed

[Art Eatman]

esheato, anybody whoever "ran the gun" in surveying with the old telescope-type transits had to understand using a vernier in order to turn angles.  It is really needed in laying out highway curves where the angles are measured down to seconds of angle.  That was part of college-freshman civil engineering long before I got into it in 1951.  Long before they had vernier calipers, for that matter.

Art

[HankB]

Art, I believe the use of verniers in surveying is virtually contemporaneous with the vernier caliper.

From http://www.woodjig.com/Gage%20tips2.htm

A little History of Calipers...Although calipers were around since the first century or earlier in China, the "graduated" caliper is credited to Pierre Vernier.

Pierre Vernier (1584-1683) (note: other sources place the dates as 1580-1637) was taught mathematics and science by his father who was a lawyer and engineer. He  worked on cartography and on surveying.  His interest in surveying led to developing instruments for surveying and this prompted the invention for which he is remembered by all scientists, the "graduated" vernier.  In his book he describes his most famous invention, that of the vernier caliper, an instrument for accurately measuring length. It has two graduated scales, a main scale like a ruler and a second scale that slides parallel to the main scale and enables readings to be made to a minute fraction of a division on the main scale.

If this source is correct, verniers on surveying instruments and the vernier caliper both came about in the early 1600's . . .

[Mabs2]

I always have a hard time with tapes because Math was always my worst subject...and the part about math I always had a hard time with was fractions.