Converting to Metric - Personal experiences only, Please

[Kev]

I'm an engineer.  I don't see the big deal.  I'm fine with using inches and pounds.  I do it everyday at work.  For me it's more difficult to work in metric since I lose my frame of reference of what the numbers mean in a relative sense (mm, kg).

Plus, for most tools, Imperial and Metric, I don't trust their built in scales.  I pull out my gauges and rulers.

[member=20208]Ajax[/member]

That surprises me, what sort of engineering do you do?

As far as scales on tools go, I tend to assess a tool's accuracy and then I know whether I can rely on it's calibration scales (Festool's track saws are a perfect example).

...

Brains become "wired" as we learn and it can be hard for some to learn new things, new languages, etc. Going from an imperial measurement system to metric can be a similar problem depending on the individual. Imagine speaking English all your life and someone told you that you now need to speak Mandarin ...

Base 10 math is obviously simpler that a combination of units grouped in 12's, 16's, etc ... but some find change really hard.

I will say that I can't see any point in going metric if you're tools are imperial, your plans are imperial and all of your suppliers provide materials in imperial.

 

[Ajax]

I'm an engineer.  I don't see the big deal.  I'm fine with using inches and pounds.  I do it everyday at work.  For me it's more difficult to work in metric since I lose my frame of reference of what the numbers mean in a relative sense (mm, kg).

Plus, for most tools, Imperial and Metric, I don't trust their built in scales.  I pull out my gauges and rulers.

[member=20208]Ajax[/member]

That surprises me, what sort of engineering do you do?

BS and MS in Mechanical Engineering
PhD on Aerospace Engineering
Licensed Professional Engineer

I do vehicle level loads and dynamics.  I write simulation codes or run commercially available ones.  The only issue with Imperial units is to have consistent mass units.  That's a simple division issue (pounds mass to slugs or slinches).  Otherwise everything else operates like metric.

 

[Kev]

I'm an engineer.  I don't see the big deal.  I'm fine with using inches and pounds.  I do it everyday at work.  For me it's more difficult to work in metric since I lose my frame of reference of what the numbers mean in a relative sense (mm, kg).

Plus, for most tools, Imperial and Metric, I don't trust their built in scales.  I pull out my gauges and rulers.

[member=20208]Ajax[/member]

That surprises me, what sort of engineering do you do?

BS and MS in Mechanical Engineering
PhD on Aerospace Engineering
Licensed Professional Engineer

I do vehicle level loads and dynamics.  I write simulation codes or run commercially available ones.  The only issue with Imperial units is to have consistent mass units.  That's a simple division issue (pounds mass to slugs or slinches).  Otherwise everything else operates like metric.

I understand ... decimal pounds or decimal kilograms makes no different to you.

To me, imperial measurements mean this ...

12 inches to a foot
3 feet to a yard
22 yards to a chain
10 chains to a furlong
8 furlongs to a mile

Then you get the specifics mainly used only in certain disciplines

72 points to an inch
12 lines to an inch
6 feet to a fathom
40 yards to a bolt
... and the many more that don't spring to mind

Imperial weight units aren't as bad as the length units.

 

[Ajax]

No.  You need to convert pounds mass to slugs or slinches in force calculations or you get errors.  Inconsistent units.  Most engineers make this mistake at least once in their career.

Length units are easy.
https://en.m.wikipedia.org/wiki/Slug_(mass)

 

[SoonerFan]

For woodworking I am mostly Festool and have converted completely.  The rest of my life however is all Imperial

 

[seandoh]

Last night I was looking at a set of four picture frames I hung between two hallway doors a couple years ago and that made my decision final.  I remembered all the fractions and confusion trying to calculate some semi-even spacing.  Sure I got it handled back then, and could do it again.  But the same excersize in metric was a whole lot simpler and probably slightly more precise (by eliminating mistakes).  That is what this is all about for me, learning a new craft and with that some new skills.

I know that I will never fully convert, imperial is too engrained in my life and those around me.  But I hope to be fluent in both, able to switch between when it suits me best.

I would to thank all for contributing and sharing, there were a lot more responses than I expected.  And it was reassuring to hear that most that tried to make the jump were successful after varying degrees of effort. 

 

[Kev]

No.  You need to convert pounds mass to slugs or slinches in force calculations or you get errors.  Inconsistent units.  Most engineers make this mistake at least once in their career.

Length units are easy.
https://en.m.wikipedia.org/wiki/Slug_(mass)

[member=20208]Ajax[/member]

I do get it .. and referenced the same source prior to responding (only your link fails to get to the right page).

Your not using units made up of multiples of 16, 14, 112, etc IN your force calcs are you??? That was simply my point.

 

[Ajax]

No.  You still don't get it.

This has nothing to do with multiples and length units.  It's about consistent mass units.  I don't see your link to working with Imperial mass units.  My link is missing the last ) but Wiki is smart enough to get you there.

You can also go here for an explanation:

http://www.engineeringtoolbox.com/mass-weight-d_589.html

The key is including gc in force calculations when working with pounds.

 

[Kev]

No.  You still don't get it.

This has nothing to do with multiples and length units.  It's about consistent mass units.  I don't see your link to working with Imperial mass units.  My link is missing the last ) but Wiki is smart enough to get you there.

You can also go here for an explanation:

http://www.engineeringtoolbox.com/mass-weight-d_589.html

The key is including gc in force calculations when working with pounds.

[member=20208]Ajax[/member]

No, my friend - you are the one lacking understanding here ...

I hope you don't make the same assumptions in your calculations as you do about people [wink]

Maybe I'm not explaining my point clearly enough for you to get it. How do I make it simpler for you? I'm not talking about the specifics of your formula or the principles you apply to your calculation ... only that when you are working within your calculations you are using consistent units, not units with non decimal increments and descriptions.

On the other hand, if you are doing this for some reason, please explain it - then we will all understand and also comprehend your reasoning.

Remember also that we're discussing the ease of using a metric measurement system based on units of ten compared to the imperial and (US "enhanced" imperial) measurement system.

I'll also take this opportunity to point out that some engineers, scientists, mathematicians, doctors, etc are woodworkers, but not all woodworkers have high numerical skills .. many are simply gifted with artistic flair or passion for what they do. Adding or subtracting two numbers consisting of feet, inches and fractions of an inch can be a real challenge for some and it's ok that that's not their skill .. but the metric system does make it easier for those people and that's where it has REAL value for woodworkers generally.

 

[peter halle]

HEY! (and yes I am shouting in either metric or imperial)  Take this argument offline - send PM's to each other - and let's move on.

Peter Halle - Moderator

 

[Holmz]

It is actually almost the key point that Kev and Ajax are discussing, and in my opinion it can be the source of some of the difficulty.

Maybe it is a slugfest?  [wink]

Namely If I am adding furlongs to feet... Then I need to have the same units. I either need to convert feet to furlongs or furlongs to feed.

It is the same with fractions... 1 and 3/16 is 19/16th, or one goes decimal and has 1.1875 inches.
It is possible to mix meters, and mm, but much easier to convert cm to mm (etc).

 

[Kev]

It is actually almost the key point that Kev and Ajax are discussing, and in my opinion it can be the source of some of the difficulty.

Maybe it is a slugfest?  [wink]

Namely If I am adding furlongs to feet... Then I need to have the same units. I either need to convert feet to furlongs or furlongs to feed.

It is the same with fractions... 1 and 3/16 is 19/16th, or one goes decimal and has 1.1875 inches.
It is possible to mix meters, and mm, but much easier to convert cm to mm (etc).

[member=40772]Holmz[/member]
You nailed it buddy! .. shame I'm so evil that I upset the karma of the universe when I simply try to express myself.

 

[Holmz]

Yes [member=13058]Kev[/member] - but the Slug part was a nod to [member=20208]Ajax[/member].

 

[Kev]

Yes [member=13058]Kev[/member] - but the Slug part was a nod to [member=20208]Ajax[/member].

Yeh .. got the sluggestion .. understood the gravity of the situation and will be attending mass tonight to atone for my sins.

 

[Holmz]

[member=13058]Kev[/member] - May the Faorce be with you.
Because a body without Higgs Bosons is just a spirit.

 

[Kev]

[member=13058]Kev[/member] - May the Faorce be with you.
Because a body without Higgs Bosons is just a spirit.

Does is matter?

 

[Holmz]

G

 

[sancho57]

in the blue corner from the fighting city of Melbourne Australia ... With a record of 52 and 4 all 52 by the knock out,

Killer Kevvvvvvv

In the red corner the challenger from parts unknown USAAAA

With a record of 38 and 1

Alex Numbers Engineeeeerrrrrr

For the thousands in attendance and the millions reading around the worlldddd

let's get ready to rummmmbbllee

 

[Kev]

in the blue corner from the fighting city of Melbourne Australia ... With a record of 52 and 4 all 52 by the knock out,

Killer Kevvvvvvv

In the red corner the challenger from parts unknown USAAAA

With a record of 38 and 1

Alex Numbers Engineeeeerrrrrr

For the thousands in attendance and the millions reading around the worlldddd

let's get ready to rummmmbbllee

[member=10147]jobsworth[/member]

I love you jobbie

 

[Stephen B]

[size=13pt]Mmmmmm, Jobworth, surely you meant to say S Y D N E Y!  [eek] [big grin] [big grin]

Alex and Kev, LOL to you both.

[attachimg=1]

[size=8pt] [member=10147]jobsworth[/member]  [member=13058]Kev[/member] [member=5277]Alex[/member]