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Egg Spurt
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Discussion Starter · #1 · (Edited by Moderator)
I have a few apps for it, but generally speaking I'm pretty bad at mathematical formulas right off the top of my head. So I find myself constantly seeing things in metric that are say..300mm.. Just a roughly 1/4" short of 1 foot, but then there's 200, 100 and so on.
Anyway..I'm sitting here just looking at the scale/tape of my saw with both metric and imperial and it dawned on me just how easy this is for making a rough estimate ..
Every 2" is just shy of 50mm.. Now that of course gets further and further away as the distance goes towards..I dunno..a mile or whatever, but close enough in short distance to get a general idea of distance with the two systems..
Where this might be handy is when you are looking for some item you might want to purchase online or whatever and the dimensions are in metric and your brain is in imperial or the other way around.
It's not a perfect system by any means, but it beats having to go find the corresponding tape or ruler or doing the math in your head every time .. I'm fairly good with wrenches and such..most of us have both metric and imperial sizes, but my brain has always stopped around 3/4"..18, 19mm?
I just thought it might come in handy for those rare conversions when your brain goes in (language removed by moderator) mode..
 

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I have a few apps for it, but generally speaking I'm pretty bad at mathematical formulas right off the top of my head. So I find myself constantly seeing things in metric that are say..300mm.. Just a roughly 1/4" short of 1 foot, but then there's 200, 100 and so on.
Anyway..I'm sitting here just looking at the scale/tape of my saw with both metric and imperial and it dawned on me just how easy this is for making a rough estimate ..
Every 2" is just shy of 50mm.. Now that of course gets further and further away as the distance goes towards..I dunno..a mile or whatever, but close enough in short distance to get a general idea of distance with the two systems..
Where this might be handy is when you are looking for some item you might want to purchase online or whatever and the dimensions are in metric and your brain is in imperial or the other way around.
It's not a perfect system by any means, but it beats having to go find the corresponding tape or ruler or doing the math in your head every time .. I'm fairly good with wrenches and such..most of us have both metric and imperial sizes, but my brain has always stopped around 3/4"..18, 19mm?
I just thought it might come in handy for those rare conversions when your brain goes in (language removed by moderator) mode..
Thanks for that mind jogger. I can visualize 0-50 or so millimeters, but for me it starts falling apart after that. Now I’ll try to visualize in 50mm increments.
 

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Egg Spurt
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Discussion Starter · #4 ·
They make tape measures with both Metric and Imperial/inch markings. All it takes is a quick glance at either measurement/number to read directly across the tape and find the equivalent.

A short cut version is that it takes 2.5 cm to equal 1 inch.
Or 10 inches equals 25.4 cm.
The point isn't whether you have access to such draconian devices..Draconian?
The point is for the times you don't feel like having to go find your draconian tape or ruler.. I know it sounds strange, but I actually have days when I get abnormally lazy. It's just a built in shortcut to indulge yourself with glorious laziness once in awhile.. Tell me..should I hang my head in shame? LOL
 

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They make tape measures with both Metric and Imperial/inch markings. All it takes is a quick glance at either measurement/number to read directly across the tape and find the equivalent.
I "had" a really nice one that went to 35 feet - while using it to assemble a metal storage shed this week, somehow, the end got all twisted up and is practically useless in metric as it probably lost 2-3mm after I tried to hammer out the krinkles. It is now dedicated to "Rough Carpentry" projects only where an 1/8th of an inch either way doesn't matter.
Oh well, back to get another one.
 

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David - Machinist in wood
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I was at the doctor's office a few weeks ago and the nurse asked my height in centimeters. I told her that I'm an American living in the United States and that she can have it in feet and inches, that if she wants to do the conversion then go ahead and do it (she just laughed and said ok). I can do the conversion in my head but choose not to in most cases. ;)
 

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25.4 MM = 1" & .03937 + 1MM


These are the only 2 formulas to remember.

To visualize in my head I roughly figure 1MM = .04"

so ballpark 10MM roughly is .400" 20MM=,800 ect 30MM = 1.200

I get goofed up in fluid measurement.
I ordered some small cups for mixing epoxy and got 30 milliliter.
My woodworking friend that's in the medical profession laughed and said
that's the size of a pill cup.
 

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If you have a smart phone, get the Tapeulator app. Enter the measurement in inches, it can calculate cm, ft, and you can convert to mm, cm, decimal inches

Fractions are a snap. I couldn't live without it!!

Examples: Left 56" Right 1 1/16"

I use metric when I need to divide distances. But I can't read mm's on a metric tape without a magnifying loupe.



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Egg Spurt
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Discussion Starter · #9 ·
I've always long considered people who are really good at doing math in their heads to be good candidates for execution, but I've never been granted a vote in the matter..Don't take it personally..I just suck at it..
Now that I think about it..suggesting someone ought to be executed is kind of personal. How about merely slapped daily and twice on Sundays?
 
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I love the metric system. It is so much more logical than feet and inches. However, as stated, visualization is the biggest problem if you grew up using feet and inches. All really good advice above.
I've posted this before. So, forgive me for repeating. I got tired of trying to visualize the differences (I'll blame it on old age). I found some measuring tools (tapes and rules) that are divided into feet, inches, and 10ths of inches (hear the brain give a big sigh of relief). It is still familiar system but, no more fractions.
The down side is that there are not many tapes on the market with those increments. It makes matters worse that many sellers don't know the difference between feet, inches, and 10ths of inches and feet and 10ths of feet that surveyors use.
If anyone else is interested, I can provide some brand names and model numbers.
 

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Discussion Starter · #11 ·
I used to think imperial was the best just because you can keep dividing inches down with a ruler to a blur.. Age kind of blows that one out of the water..I don't generally work with a microscope to mark out 1/128th or god forbid 1/256ths.. I do however have feeler gauges, but I don't usually hold the edge of them up to a wooden yardstick to check the actual thickness..
 

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David - Machinist in wood
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It is so much more logical than feet and inches. However, as stated, visualization is the biggest problem if you grew up using feet and inches.
That's the biggest issue for me, the visualization. Tell me you need a distance of 5' 6" and I can approximate that with ease but tell me to show you what 168 cm is and I'm lost (unless I do the conversion to Imperial).
 

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I've always long considered people who are really good at doing math in their heads to be good candidates for execution, but I've never been granted a vote in the matter..Don't take it personally..I just suck at it..
where do i need to kneel to have my head parted from my neck??? 😂

i use to do a lot of rough estimates for an italian company doing projects at the big 3
i was pretty good at converting mm & M in my head and back again
we made a lot of money on my rounding up rule. that was 20 yrs ago.
fwiw, my all imperial rule showed up, i like it a lot, no more tenths or mm anywhere on it (y)
 

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I have a few apps for it, but generally speaking I'm pretty bad at mathematical formulas right off the top of my head. So I find myself constantly seeing things in metric that are say..300mm.. Just a roughly 1/4" short of 1 foot, but then there's 200, 100 and so on.
Anyway..I'm sitting here just looking at the scale/tape of my saw with both metric and imperial and it dawned on me just how easy this is for making a rough estimate ..
Every 2" is just shy of 50mm.. Now that of course gets further and further away as the distance goes towards..I dunno..a mile or whatever, but close enough in short distance to get a general idea of distance with the two systems..
Where this might be handy is when you are looking for some item you might want to purchase online or whatever and the dimensions are in metric and your brain is in imperial or the other way around.
It's not a perfect system by any means, but it beats having to go find the corresponding tape or ruler or doing the math in your head every time .. I'm fairly good with wrenches and such..most of us have both metric and imperial sizes, but my brain has always stopped around 3/4"..18, 19mm?
I just thought it might come in handy for those rare conversions when your brain goes in (language removed by moderator) mode..
I hate both being here in this country. I could use either system but I wish they could pick one and do away with the other.
 

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As I get older, working with the imperial measurements became more of an issue. I even have an app on my android phone (FractionPlus Pro) to do the math but I still prefer metric where I don't need to work with fractions. It is much easier for me to add two or more metric numbers than two or more imperial numbers, assuming I don't have my app. I also created a table, "Inch to Decimal to Metric for one inch" that I've posted in a few locations in my shop (see the attached PDF).
All of my measurement tools have both scales on them.
 

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Discussion Starter · #17 ·
I use fraction plus a lot.. I keep telling myself I should use metric, but I'm stuck in my ways I suppose..
 

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Discussion Starter · #18 ·
Strange thing with visualization is I can visualize an entire project, furniture, cabinet, etc., and just work from imagination a lot, but toss numbers into the mix? I can write pages upon pages and probably get most of it past the college English department, but take me across the hall to the math department and I'm dead meat.. 😄
 

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I finally adopted an English/metric tape measure. When I need to cut long boards down into, say, 7 equal pieces it is so much easier to work in metric. That, and so much material we get these days is actually milled metric (even here in America? You betcha!). So a formerly 1/2 inch sheet of ply is sold as "actual 15/32 inches" at the big box, which is amazingly close to 12mm, the metric equivalent of 1/2 inch ply ("1/2 inch" baltic birch is 12mm thick). Now all you real Americans can think back to when they first sold this notion on us that they "sanded" the face plys down to 15/32. Bull. Hate to disappoint you -- you've gone metric, and they didn't even ask nicely.
 

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I specifically bought a tape with both imperial and metric..***if it didn't grow legs after a few weeks and run away.. I blame the metric system for that..
On the other hand..you gotta love trying to divide certain imperial measurements and come up with something like 6 and 5/7s. I lost my 7ths of an inch ruler..
 
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