Question but i'd hoped to spend MORE...

netsol

New Member
when it comes to new toys, i am not as cheap as you would expect
for some of our fabrication projects, i have been looking for a good digital protractor (or specifically a sliding t-bevel)
i would like to deal with these spec's the same way you deal with color management/profiles, in my fantasy, if a client asks for a repeat order a year or two from now, we can just look in their file & build,
without paying for someone to redraw. AND EVEN, if something is damaged, we could simply reference customer files and reproduce a part, without having to be in front of the damaged item to make
measurements


the machinists among you MAY laugh at me, but it is no secret to you that regular people are not terribly accurate making this type of measurement

i don't really want a $42 dollar item from home depot, i was was hoping for something from Starrett (something that comes with a recalibration procedure)
 

Humble PM

New Member
I think you are possibly looking for a Precision Universal Bevel Vernier Protractor. Not digital, but very precise, recalibratable and comes from Starrett.

And rather expensive.
 

netsol

New Member
Not digital is fine, if I am using it
An analog dial, introduces too much user error
55 years ago, in junior high, I took a metal shop course. The instructor passed around a tape measure and a slightly irregular piece of metal. ALMOST RECTANGULAR.
everyome in the class, took their time and measured, did a drawing and wrote down the results
Long and the short is, NO ONE WAS CORRECT.
I learned a lot from that. Measure twice, cut once & you still get errors
I think,I will buy 2 instruments.
The one you suggested and some sort of a digital readout device

That way, no matter who uses it, our records will reflect, potentially, the correct Value

Thank you for your help. I will order tomorrow
 

James Burke

Being a grandpa is more fun than working
I'm one of the resident tool and die makers. Save your money. I believe a universal bevel protractor is overkill, especially since the blade of the protractor will not be as long as your entire project.

A one-degree error in the span of one inch equals .017". Compound that out across 36 inches and you pick up a total error of .612"...which is just shy of 5/8".

If it were me, I'd use trigonometry (specifically, the tangent function), a high quality framing square and a steel engineer's scale (precision ruler). With a few quick calculations, you will have a far more accurate measurement over long distances. I guarantee it. Essentially, you will be measuring the "amount of variance" across a given distance (otherwise known as "delta"). See my example below.

If your measurements were correct to within 1/32" across a 36" span, you'd be accurate to within nearly 3 minutes (1/20 of a degree). Again, the bevel protractor won't be able to reach out that far. For welding/fab work, you should easily be able to get within 1/16", which would put you within 1/10 of a degree across long spans.

And when it comes to designing, only a CAD program will give you angular measurements accurate within minutes and seconds (and if you're using decimal degrees, that would be four to six decimal places out) . BUT, by using trig and a scale, a CAD program is not necessary, so long as you hold your linear measurements to within three decimal places.

Hint: With the exception of the square and scale, that's how surveyors do it. And if they can be accurate to within a fraction of an inch across miles, you know it can't be all that bad. Also, the Egyptians did a pretty darn good job squaring up the pyramids using the same methods.

If you're ever in my neck of the woods (southern lower Michigan), stop by some time. I'll also share some other cool machinist measuring techniques helpful for layout and design.



JB


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James Burke

Being a grandpa is more fun than working
Funny post considering half the people here probably can't even read a tape measure
Yep, I suppose so. It all boils down to those damn fractions most of us struggled with as kids. But once I got into shop class in junior high, it all made perfect sense.
Over the years, school systems have disemboweled nearly every practical "hands-on" course my generation knew. I surely hope things turn around.

Computers were slowly introduced in the early 80s, and the main rationale was to develop "tech savvy" kids. Fast forward to today, and schools are filled to the brim with computers...and sadly, not very many teachers.

JB
 
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WildWestDesigns

New Member
Computers were slowly introduced in the early 80s, and the main rationale was to develop "tech savvy" kids. Fast forward to today, and schools are filled to the brim with computers...and sadly, not very many teachers.
And ironically, not very tech savvy kids either given what is abstracted away from kids in OSs nowadays.

And you hit it with with practical hands on. That is what connects the dots for so many. Not just the theory, but seeing the application of said theory at work.

We didn't have shop, but what saved me with math, measuring and the like was working for my mom (which those types of avenues are also going away as well it seems). Knew all kinds of tricks that people just don't use and/or know anymore.

Further compounded, in my opinion, as to what is thought of as "higher" education versus other type of education. That type of phrasing comes with baggage attached to it.
 

James Burke

Being a grandpa is more fun than working
All I got was James Burke wants us to get a TAN when the sun is at a good known angle...and my bikini chick can get "hands on" with my lotion.
Tex, you seem to know all the angles. Perhaps you could share some more info on this bikini chick...perhaps a little more description utilizing French curves and measurements...or as they used to say in drafting class "descriptive geometry".



JB
 

Notarealsignguy

Very Big Member
We didn't have shop, but what saved me with math, measuring and the like was working for my mom (which those types of avenues are also going away as well it seems). Knew all kinds of tricks that people just don't use and/or know anymore.
I think this has a lot to do with things today. It was more commonplace for kids to be dragged into work with their parents 20-30+ years ago. You can't do that anymore unless you are self employed and I would bet that those numbers have dropped as well. You need life experience in addition to formal education, it's not the education itself that is bad today. It is also not the job of schools to do this, this is the job of the parents. Unfortunately, many people today look down at having kids work or doing things that the know nothings consider dangerous.
 

WildWestDesigns

New Member
It is also not the job of schools to do this, this is the job of the parents.
It's strange that things that the school used to teach, no longer do so and things that they shouldn't teach, they do now.

And bare in mind, when some of these changes started happening, is when we started having a generation do worse compared to the previous one.


So yes, I would say education is definitely a part of the issue here. Now are there parents that are lackluster, sure there are. Always have been, always will be. Although with social media now, stupidity seems to have been amped up.

But that still doesn't change the issues with the school system and how it's handled in current day.

The further away one gets from a time when things were done more often, eventually there is no memory of it, so how can it be passed down to the next generation?

As to this:

Notarealsignguy said:
...unless you are self employed and I would bet that those numbers have dropped as well.

Yes it has, but that is also how things have been perceived and how the school system has structured itself that it really dissuades from that.

Think about it, the higher education is predicated on the student jumping through these hoops to get employment from someone else. That's how it's sold to people, to make the student more appealing to potential employers. Not to start their own business.

That's how it's approached. Shoot in my college when I was there, Entrepreneurship was an elective, not even required in any business degree. Mileage may vary on that one, but that's the way that it was when I was at my college.

Not to mention how the economy has been handled the last couple of years depending on the state/county that one is in. Hasn't done to well for self employed people as a whole.

It seems like there is this underlying way of thinking that's trying to do away with self reliance, being self sufficient. Of course, that would also depend on ownership of things as well and that isn't what it used to be either.

Shoot, civics, proper civics, should be brought back (I know some people on here have even mentioned that they don't fully pay attention to politics and the like and that's part of the issue as well, some people aren't going to like reading that, but that doesn't in of itself make it not true).
 

netsol

New Member
I don't understand how a protractor is going to help you by giving you an angle readout.
It won't, if I am doing the measurement. I am dumbing down the process for other workers who shall remain nameless (unless they start following this website)
 

netsol

New Member
Yep, I suppose so. It all boils down to those damn fractions most of us struggled with as kids. But once I got into shop class in junior high, it all made perfect sense.
Over the years, school systems have disemboweled nearly every practical "hands-on" course my generation knew. I surely hope things turn around.

Computers were slowly introduced in the early 80s, and the main rationale was to develop "tech savvy" kids. Fast forward to today, and schools are filled to the brim with computers...and sadly, not very many teachers.

JB
James, I REALLY enjoyed algebra a geometry, (although trig and calculus was not nearly as much fun,) I actually had to work at it and I resented that

It's really sad we don't have more hands on learning
 

James Burke

Being a grandpa is more fun than working
James, I REALLY enjoyed algebra a geometry, (although trig and calculus was not nearly as much fun,) I actually had to work at it and I resented that

It's really sad we don't have more hands on learning
Good news...the trig problem is really nothing more than a plane geometry problem (solving for an unknown side or angle), so you should be good. Don't let the word "trig" fool you.

But yeah...I get you....trig proofs, axioms, postulates, theorems, etc... could get a bit complicated.



JB
 
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Notarealsignguy

Very Big Member
It's strange that things that the school used to teach, no longer do so and things that they shouldn't teach, they do now.

And bare in mind, when some of these changes started happening, is when we started having a generation do worse compared to the previous one.
I disagree. Shop and those sorts of vocational classes aren't really relevant today. The old ways of doing things are now hobbies. What's the point of teaching a kid to use a lathe when we have CNC machines and the majority of the products built in shop class are now made overseas? There's no point in teaching auto mechanics, it's going the same way. People don't tear down engines anymore or rebuild parts, you replace them. It's all computerized diagnostics and following steps. What about drafting when that too is computerized? You can't hang onto the past.
 

Texas_Signmaker

Very Active Signmaker
I disagree. Shop and those sorts of vocational classes aren't really relevant today. The old ways of doing things are now hobbies. What's the point of teaching a kid to use a lathe when we have CNC machines and the majority of the products built in shop class are now made overseas? There's no point in teaching auto mechanics, it's going the same way. People don't tear down engines anymore or rebuild parts, you replace them. It's all computerized diagnostics and following steps. What about drafting when that too is computerized? You can't hang onto the past.
What would be useful is shop class, plumbing basics and welding intro. Intro classes to the trades so a kid has exposure and options when they graduate or at least a basic understanding of how to fix a leak when they're older.
 
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