dang metric!

[HowardH]

Uncle Bob was kind enough to forward along the Parallel Guide Set (after I was kind enough to give him my CC #).  It was short a part, it was missing one of the brass adjustment screws and matching nuts but Bob is sending this out although it appears they aren't really that necessary as it is pretty square anyway.  As a old U.S. imperial measurement guy from way back, this metric thing is driving me nuts.  For example, I am building a shop cart using a set of Lee Valley plans that uses U.S. measurements.  For me to make the narrow strips the plans call for, I had to take their measurement, divide the fractional part to get it into a decimal form, add the number of inches (2 3/4 being 2.75 for example) and multiply by 25.4 to come up with an approximate metric measurement.  Then you have to set the stops the approximate the metric equivalent and hope it's close enough.  I see what Brice was talking about in re: the gap between the edge of the tape to the edge of the rail.  You do have try to look closely.  One would think the US market in large enough to warrant manufacturing a U.S. inch scale so we don't have to do so much math and introduce the possibility of error.  I found myself multiplying once by 24.5 instead of 25.4 so a couple of pieces are slightly off.  Am I being too much of a U.S. homer?  I like the simplicity of metric and if the plans came in metric measurements, it would be no problem.  Just venting a bit.  Like the unit a lot, a bit of a pain to get used to but it delivers as advertised.  Keep your calculator handy, though...

 

[JeromeM]

 As a old U.S. imperial measurement guy from way back, this metric thing is driving me nuts.  For example, I am building a shop cart using a set of Lee Valley plans that uses U.S. measurements.  For me to make the narrow strips the plans call for, I had to take their measurement, divide the fractional part to get it into a decimal form, add the number of inches (2 3/4 being 2.75 for example) and multiply by 25.4 to come up with an approximate metric measurement.  Then you have to set the stops the approximate the metric equivalent and hope it's close enough.  I see what Brice was talking about in re: the gap between the edge of the tape to the edge of the rail.  You do have try to look closely.  One would think the US market in large enough to warrant manufacturing a U.S. inch scale so we don't have to do so much math and introduce the possibility of error.  I found myself multiplying once by 24.5 instead of 25.4 so a couple of pieces are slightly off.  Am I being too much of a U.S. homer?  I like the simplicity of metric and if the plans came in metric measurements, it would be no problem.  Just venting a bit.  Like the unit a lot, a bit of a pain to get used to but it delivers as advertised.  Keep your calculator handy, though...

Some time the US will catch up with the rest of the world   and then things will be easier.  ???

But until then why not print from http://www.metric-conversions.org/cgi-bin/util/conversion-chart.cgi?type=2&from=16&to=6 that one is from 0.1 up to 1000 inches or http://www.metric-conversions.org/conversion-charts/length/millimeters-to-inches-conversion-chart.pdf

 

[rwdawson]

Howard,

You are experiencing the most difficult part of going metric -- mixing metric and imperial measurements.  And, to make it more frustrating, a Canadian company is trying to make it easier for Americans by catering to our perceived needs.  If they stuck with metric, like the rest of Canada, you wouldn't be ranting.

The conversion chart is a good idea.  Another one is to get a tape measure that reads both imperial and metric.  Fastcap has one, as do several other manufacturers.  The Wixey digital calipers measure imperial and metric.  Sometimes I set mine to the desired imperial reading, then press the mm button to go metric.  Of course, you can also measure things with it, but you are limited to the six inches or so capacity of the device.

HTH,

Richard

 

[HowardH]

I have a conversion chart on the wall in my garage/shop but it is still easier to get a more precise conversion by using a calculator.  If it comes out to some decimal of a mm, then that's usually close enough.  I can't see that close.  I suppose I could take all the plan measurements and put the metric equivalent next to them or design my own plans from scratch using metric but I'm not quite that good yet.  I'll get there eventually.  I still have a hard time visualizing how long something is when it is stated in MM.  Tell me 12", no problem!  Say 305mm and I'll be going "huh"?  I bought the Festool tape to help me along.  It works pretty well but the graduations are a bit hard to read.  I have a similar digital gauge. I'm trying to go metric but they don't make it easy!  BTW, the plans showed the plywood in both metric and U.S. units.  It called for 6mm, 12mm and 16mm ply.  I took my calipers with me to Lowes so I could make sure I was buying the right thing.  Metric ply is very difficult to find down here. 

 

[polarsea1]

I bought several of the Fastcap metric tapes and they've been a great help. I ballpark things in imperial then use metric to build.  :

 

[Vindingo]

I have been wanting a standard mesuring strip for my TS55 depth gauge.  I know that it uses mm, but for some reason I just think of them as numbers. If I want to cut 3/4" ply  put it on #27, not 27mm (in my head)     

 

[fshanno]

I haven't done it yet myself but I'm wondering if there is any reason why the metric tapes couldn't be replaced with and imperial peel and sticks.  And when replacing go ahead and get the edge of the tape closer to the stop.

 

[Birdhunter]

Hey Alexa...... convert 3/8” to metric. “3/8” is 9.525mm

 

[Bob D.]

"One would think the US market in large enough to warrant manufacturing a U.S. inch scale so we don't have to do so much math and introduce the possibility of error."

Like everyone else in the US I was brought up with the imperial system of measurement, but we were also taught the metric system and told "someday soon everything will be metric so you'd better learn to like the metric system" or words to that affect. That was 50+ years ago for me, and the powers that be have resisted making the change for decades, which has led to some disasterous results. So we are left in a place that is worse than we were before the tried to move us to the metric system, and that is a mix of both systems.

Most of that resistance I would guess (myassumption, no proof) is that manufacturers are the ones behind the move to block adoption of the metric system here, at least in the beginning. I base that on they would have incurred the greatest expense in making the change. Since this all happened beofre computers ruled the World imagine how difficult it would have been to change all your documentation and machinery over to metric, not to mention the growing pains of a workforce that while exposed to the metric system does not fully embrace it nor are they comfortable enough working with it to be second nature.

Never mind that the metric system is much easier to calculate, everyone still thinks in feet, inches, and fractions. And I am one of those. When I look at something and guesstimate its length I don't think to myself that's 35 mm long, I think that looks to be about 1-3/8", not even 1.375, but one and three eights inches. I bet most of us do the same if you're here in the US. That mental picture of length or volume that we carry around is what holds us back as individuals I would suspect. I can't think in terms of milliliters or millimeters and pressure is even worse. How many PSI is one Pascal or one Bar, I don't have a clue.

I can look it up, use an app on my phone, or ask Alexa, but those all take time and subconsciously probably make people feel inferior that they have to seek outside help so they go with what they know anad stick to Imperial measurements.

The auto manufacturers and other industries that manufactuer and sell on a global scale have seen the light and changed over long ago. And though many government agencies use the metric system that spark has not been enough to generate a following and move us to catch up with the rest of the World. Just another part of our isolationist mentality I guess. The argument will be why do I have ot change just because everyone else has or metric is not better just different or one of a dozen other lame reasons for holding back.

I didn't read though this just providing it for your reference. It's almost comical how we have resisted the change, but someday, maybe in my grandkids lifetime, we will convert.
https://en.wikipedia.org/wiki/Metrication_in_the_United_States

 

[jcrowe1950]

Howdy Folks,

For me, the conversion to metric is not a big deal for construction of cabinets etc. If using LR 32, for instance, it all makes sense. My challenge, when I lived in Sweden, was kilometers as in driving speeds. 110 kph seems really fast until you do the conversions...68 mph and change. 8)

 

[casper]

If I have to convert from metric to imperial I use a digital vernier caliper, set it to the imperial scale and press the button for the imperial equivelant. 

 

[Bugsysiegals]

Hey Alexa...... convert 3/8” to metric. “3/8” is 9.525mm

I’ve Alexa in the shop but since I’ve mostly metric rules I’m usually asking her to add/subtract ... works great!

I also have tape measures or rules with both imperial/metric. I recommend SS Starrett rules which have both ... I have 4 different lengths going up to about 3’. The metric Woodpecker tools align with the Starretts. NOTE: not all rules have equal spacing and are different so make sure if you use different ones during a project that they’re all laid out the same. I have a Stanley metric/imperial tape measure which is exactly the same as Starrett but the repeating numbering of 1-9 after each 100cm caused me to have errors so I’ve now a True32 tape measure which is slightly off from my Starretts but is in mm and is close enough ... 0.5mm off over 1M.  Metric may seem hard at first but you’ll quickly remember 25.4, moving the decimal one place, 3/4” is 19mm, 4x8’ sheets are 1220x2440mm, and you start getting a general sense of things as you make projects. See my thread about I keep cutting things short for some helpful ideas to not make these mistakes when using metric.

 

[Jim_in_PA]

Hey Alexa...... convert 3/8” to metric. “3/8” is 9.525mm

There you go...bringing back a necro-thread specifically to make us buy another "tool" for the shop. I guess Amazon gets some more of my money. LOL

Seriously, that's a great idea...I work mostly in metric now for the last two years and love it, but have some clients that require Imperial. When I must make a conversion, I've been using the browser on my CNC computer or my "shop Mac". It sounds like (literally...sound) that an Alexa or Siri based assistant might be a great alternative.

 

[ChuckM]

Snip. 110 kph seems really fast until you do the conversions...68 mph and change. 8)[/color][/size][/font]

When I drive in the States, I keep doing math in my head to be sure I won't get tailgated on the highway. I have to constantly do the multiplication of 1.5 (faster than doing the 1.6 operation) on the road. If I have a GPS in the car, I can save the calculations and slow down when I hear the voice alarm.

 

[wmarazita]

Gosh, it would never even occur to me to try and convert imperial to metric so I could use the rules to set the distance of the parallel guides to cut strips of plywood. I would simply measure and pencil mark the distance I needed on both ends of the plywood with an imperial tape, set my guide rail on the plywood so the marks are split in half by the cutting strip of the guide rail, and then set the parallel guides in place so that it was repeatable for the next cut. Done.
Maybe I am missing something?

 

[Cheese]

If I have a GPS in the car, I can save the calculations and slow down when I hear the voice alarm.

In the states...we all employ the voice alarm.  [big grin]  It's what enables us to retain our drivers license.  [smile]

 

[Bugsysiegals]

Gosh, it would never even occur to me to try and convert imperial to metric so I could use the rules to set the distance of the parallel guides to cut strips of plywood. I would simply measure and pencil mark the distance I needed on both ends of the plywood with an imperial tape, set my guide rail on the plywood so the marks are split in half by the cutting strip of the guide rail, and then set the parallel guides in place so that it was repeatable for the next cut. Done.
Maybe I am missing something?

The level of precision desired varies person to person.  I bought the Incra fence for my table saw so I can have the highest level of precision possible.  I dislike inaccuracy so much that I only use the guide rail to rough cut items to size and then run panels through the table saw to ensure panels are parallel.  I wish I wasn’t so up tight about it as it’s extra effort but I know I cannot be precise with pencil lines, tape measure hooks flexing, guide rails not being exact, etc.

I’m currently working on adding a threaded rod into my Incra parallel guides so they work like the Incra fence. If I can get it working like the Incra table saw fence, I’ll be able to trust ripping to final size with the  TS55, have repeatable width cuts, etc.

Or maybe this level of precision is overkill for woodworking and being off by 0.5 to 1mm only matters to a few crazy people like me!!

Sent from my iPhone using Tapatalk

 

[JeromeM]

Most of that resistance I would guess (myassumption, no proof) is that manufacturers are the ones behind the move to block adoption of the metric system here, at least in the beginning. I base that on they would have incurred the greatest expense in making the change. Since this all happened beofre computers ruled the World imagine how difficult it would have been to change all your documentation and machinery over to metric, not to mention the growing pains of a workforce that while exposed to the metric system does not fully embrace it nor are they comfortable enough working with it to be second nature.

Incorrect assumption, and trying to fit the case to the guess.
Having lived and worked through a conversion to metric the reason is much more likely to be the fact that when it was tried in the US it was pushed too hard too fast. In the U.K. the process took decades to complete.

The pushback came from individuals. Industry changed when the machine lifecycle dictated because the metric machinery was less expensive. It was the same with fasteners, over time imperial went from cheaper to more expensive, industry bought the cheaper quality products, so industry changed faster than the general population.

 

[Svar]

Having lived and worked through a conversion to metric the reason is much more likely to be the fact that when it was tried in the US it was pushed too hard too fast. In the U.K. the process took decades to complete.

UK is an outlier in terms of how long it took. In most countries conversion was much quicker. That includes Commonwealth countries, that started later and finished earlier than UK.

 

[wmarazita]

Gosh, it would never even occur to me to try and convert imperial to metric so I could use the rules to set the distance of the parallel guides to cut strips of plywood. I would simply measure and pencil mark the distance I needed on both ends of the plywood with an imperial tape, set my guide rail on the plywood so the marks are split in half by the cutting strip of the guide rail, and then set the parallel guides in place so that it was repeatable for the next cut. Done.
Maybe I am missing something?

The level of precision desired varies person to person.  I bought the Incra fence for my table saw so I can have the highest level of precision possible.  I dislike inaccuracy so much that I only use the guide rail to rough cut items to size and then run panels through the table saw to ensure panels are parallel.  I wish I wasn’t so up tight about it as it’s extra effort but I know I cannot be precise with pencil lines, tape measure hooks flexing, guide rails not being exact, etc.

I’m currently working on adding a threaded rod into my Incra parallel guides so they work like the Incra fence. If I can get it working like the Incra table saw fence, I’ll be able to trust ripping to final size with the  TS55, have repeatable width cuts, etc.

Or maybe this level of precision is overkill for woodworking and being off by 0.5 to 1mm only matters to a few crazy people like me!!

Sent from my iPhone using Tapatalk

Yes, I agree with almost everything you say. But I’m not sure it helps solve the OP’s frustration with feeling the need to convert imperial to metric (“dang metric!”). Whether I am using imperial or metric measurements has no bearing on my accuracy and precision. If I use math to convert from one system to the other, I would be worried about introducing an extra step that probably only increases the chances of error (an error like the OP said he made by multiplying by 24.5 instead of 25.4). And once converted, I still have to measure at some point to see if my setup and cut was accurate. The level of accuracy comes from the type of measuring and marking: a tailor’s cloth tape and crayon vs. a metal hook tape measure and pencil vs. a Woodpecker steel rule and marking knife; etc. The accuracy I shoot for is always dependent on the project (I don’t shoot for the same level of accuracy when I am cutting a 2x4 to frame a wall as I do if I am cutting joinery for a wooden jewelry box). But in almost all projects, the repeatability of similar parts (precision) is usually crucial. Once set accurately, the parallel guides should provide the precision the OP is looking for.