Converting Millimeters to Fractions

Very cool. Thanks.

-- When you give someone a chance it may well be their last.

Thanks, Charlie!

This will be great laminated and hanging in the shop.

Lew

Thanx! a good reference to keep around….. now if everyone would only work in metric…. we wouldn’t have these problems to begin with would we? lol…

sorry, but metric just makes sense, and working in fractions is a pain in the a$$ sometimes.

-- My Drinking Club has a Woodworking Problem...

Thanks Charlie. Print out nice on the color laser.

-- Karson Southern Delaware karson_morrison@bigfoot.com

I couldn’t agree with you more. But the old inches and fractions system just wont die.

If I’m not mistaken, it was something like 30-40 years ago when it was officially announced that the U.S. would be going to the metric system. I guess the wheels of progress turn slowly, huh? :-)

-- Charlie M. "Woodworking - patience = firewood"

Charlie,

I really apprciate your sharing this with us. This will come in soooo handy!

-- My woodworking pictures http://s107.photobucket.com/albums/m292/bnoles616/

That’s pretty handy… looks like a good reference to put in the shop… Thanks Charlie!

-- As iron sharpens iron, so one man sharpens another. (Proverbs 27:17)

That’s going in the shop. Thanks for the effort!

I definitely appreciate your work on this but I won’t be using it. sorry. Canada had the metric system forced on us a number of years back and one thing I have learned in that time is to never convert.
If it’s in imperial measure use imperial. If it’s in metric use metric. The cost of appropiate measuring instruments is very low compared with the aggravation and inaccuracy of converting. Just the opinion of one ticked Canadian. It wasn’t broken and didn’t need fixing.

-- If we learn from our mistakes, I'm getting a fantastic education.

LOL, MrWoody!

I’ll try not to take it personally. :-)

-- Charlie M. "Woodworking - patience = firewood"

I know what you mean I have sliding ruler that works well but get yourself a tape measure with both English on top and Metric at the bottom

-- - - Tools are nice to have but you need someone to work them - -

Thanks Charlie. I use both out in the shop. At time I find that metric is more accurate.

The chart is super.

-- The significant problems we face cannot be solved by the same level of thinking that created them

It prints well in good ole b&w too. Thanks Charlie, great idea.

Thanks Charlie,

I am lucky, I have a built in converter on my cell phone:)

Callum

-- There is no such thing as a mistake....just a design modification Check out my site http://thetimberkid.blogspot.com/

Thanks, Charlie. Powerful tool, that Excel. One of the best things Bill Gates ever sprang on us (I recall trying to use Lotus123 with a great deal of wailing and gnashing of teeth).

-- "Bordnerizing" perfectly good lumber for over a decade.

Doug, do we have to say anything nice about Bill Gates? (I do love Excel, though. I’ve used it for years and am still finding new things I didn’t know it could do.)

Callum, be careful using that cell phone in the shop! :-)

-- Charlie M. "Woodworking - patience = firewood"

Charlies,

Thanks for the converter… Now I won’t have to write one!

-- Chris

Thanks for the chart, Charlie. I’m sure it will come in handy. Very colorful too. You DO have too much time on your hands, to sit down and create this. Or is it too much Luzianne (w/chickory)?

-- Tim -- http://tmuli.com

THIS SITE MAKES CONVERSIONS EASY.
http://www.worldwidemetric.com/metcal.htm

-- Only the Shadow knows....................

John, that’s a good site. I have a little conversion calculator on my desktop that does the same thing also. But for me, the missing element that I always seem to be looking for is the mm to fractional inches conversion. I could not find that on the internet anywhere. (I’m sure someone will provide a link to prove me wrong.)

-- Charlie M. "Woodworking - patience = firewood"

I had a guy once told me he wanted a board ripped two and two thirds inches wide. I told him i couldn’t help him because it wasn’t on my ruler. Lol

As for metric. I admit its a better system. I think the answer to why we haven’t converted can be found in Americans general distaste for most all other things European. Now i’ve stepped in it!

-- miles125, Alabama.."Architecture is frozen music""

How un-politically correct of you, Miles!

Besides, we don’t dislike everything European. Particularly those French and Italian women come to mind (at least the ones who shave their underarms).

There…. now I’ve insulted Europeans and feminists in a single comment. :-)

-- Charlie M. "Woodworking - patience = firewood"

Shame on you Charlie, now we are having the metric -v- imperial discussion again ;)

Too bad we don’t have 12 fingers. 12 is a more natural number for archetectural measurement since it can be evenly divided in so many ways. 10 sucks since it can only be divided evenly by 2 and 5. It’s multiples are just as bad. 20 can only be divided by 2, 5 and 10 while 24 can be divided by 2, 4, 8, and 12 which as you can see are all themselves divideable into halves and quarters because they don’t have that ugly 5 in the middle.

-- Scott - Chico California http://chicowoodnut.home.comcast.net

Nice to see a comrade step in it with me!

As for converting metric to fractions. You really get a skewed result. Because theres too much rounding off going on. Lets say you decide 17mm is 11/16ths. Then when you multiply 11/16ths by say…50…you get a far different answer than 17 mm x 50. Getting to intimately know fractions by their decimal equivalents is the way to go for math purposes. After years i pretty much know the decimal equivalents of all fractions from 1/16th to 15/16ths in my head.

-- miles125, Alabama.."Architecture is frozen music""

This ones a keeper Charlie.

-- Bruce from Central New York

Miles, you’re right about the fractions never quite being right. But I guess the applications I had in mind making the chart were more of the “in the ball park” variety. For example, I’m installing some hinges that came with screws, and the instructions say to drill 4mm pilot holes. If my bits are all fractional, what good is a decimal equivalent unless I have the corresponding bit size committed to memory. With the chart, I can look and see that 11/64 will do just fine.

-- Charlie M. "Woodworking - patience = firewood"

Charlie did you know that Excel is just a knock off the on original Visicalc that came out when Bill Gates was teething. <vbg>
I used it on my TRS 80 Model I an II with 8 inch floppy discs.

Bob

-- A mind, like a home, is furnished by its owner

Thank you Charlie

It’s a good conversion table even for me….a Metric guy :-)

Working in aviation for 36 years, I’m used to work with English because…...Boeing makes the airplanes in Inches, Feet and Knots but in my “civil” life, I work always with metric…well, living in metric countries…

I can use this chart when I’m adding text to my pictures so they will be “Bilingual” (I’m posting in Australian, 2 Italian, 2 UK, Canadian, a few US and Brazilian forums).

What “Kills” me in the English measuring system is that, on my rulers and measuring tapes, the beginning is 32 or even 64th but later it becomes 16th so, if I need to measure, say, 10-5/64, I don’t see it there.

Another “killer” for me is that, if I want to measure, say, 10¾”, it’s also not written there…I have to convert it to 12/16” and look for the lines….

If you were using everything in say, 32nds or 16th – like 28/32” or 4/16” it would be much easier for me to measure….well, I believe that for you guys it comes natural…

Regards
niki

Niki, I’m not quite sure I follow. On most rulers, the lines for different increments are different lengths. For example, the longest lines between inches are often the ones that are 1/4” apart. So if you want to mark something at 10 3/4, you look for the 10, then count 3 long lines over. I guess it does seem more natural if you’ve been doing it that way all your life.

Bob #2, I didn’t know that. And I’m going to pretend I’m too young to have ever seen an 8” floppy. :-)

-- Charlie M. "Woodworking - patience = firewood"

Thanks. Lets see where else metric can help… How many hours are in a metric day? How many months in a metric year? Not everything is based on tens. Woodworking in inches makes sense when you contemplate the width of a standard blade kerf. Think about it.

-- making sawdust....

Hi Charlie

Yeh, that’s what happens when I talk without pics :-)

On the pic below, you can see that, up to 6” the graduation is 32 and from 6” – 16 so how I’m going to measure 10-5/64” but…maybe on your tapes you have a better graduation that this “bilingual” one :-)

And than I have to count too many lines and not only but if I have to measure 5-3/8”, I have to “translate” it to 5-12/32” so, I’m writing (or reading) one number (5-3/8”) and measuring different number (5-12/32”) and that’s a little bit confusing if I’ll compare it to the Metric that I write, read and measure the same number.

I’m sure that for you it comes much more natural but for a “non-native English measuring system” it’s a bit of confusing…

Now, let me give you a compliment….look at the ruler below the tape – it’s made by “General” and it’s “Made in USA”- I have it since 1965 and after 43 years it looks as new as it was….well, when the thinks were “Made in USA”.....

Regards
niki

I understand now what you were saying, Niki.

Different rulers are designed for different purposes, and so there are many different ways of marking the graduations.

But think about this… A millimeter is much larger than 1/64, so if you wanted to measure something in millimeters as precisely as 10 5/64, that metric tape would not be too accurate either.

-- Charlie M. "Woodworking - patience = firewood"

Hi Charlie

I’m only an amateur but for the last 13 years I never had to measure or cut less than 1mm…(I also cannot see less that 1mm…getting 64… :-) )

Maybe we (I mean – Americans and Europeans) have different thinking. I did not see Metric plan calling for xx.5mm or xx.25mm…everything is given in full millimeters.

Usually, I plan the cabinets dimensions myself (with general dimensions given by my wife – the designer) and I plan it down to 1mm.

I don’t think that you’ll have a problem to plan a cabinet with all the dimensions down to /32” or even /16”

The only time that I have to measure less than 1mm is when…..I align my table saw blade with the caliper… :)

Best Regards
niki

Niki, I’m lucky if I can cut a board to within 1/16th of what I want. :-)

-- Charlie M. "Woodworking - patience = firewood"

There are quite a few examples in woodworking where we do indeed need to be more precise than nearest 1/64th or millimeter. Lets say you want to divide a 62 inch space into 45 equal increments. Or if you’re metric you round off that dimension to 1575 mm and divide by 45 equal increments. Either way, for purposes of accurate math calculations, you’re going to have to convert both systems to decimal places far more accurate than a millimeter or 64th to avoid arriving at an answer that is not just off, but considerably off. Just because a minute measurement is not visible on our rulers doesn’t mean they don’t play a crucial role in the math involved in our work.

By the way, theres a name in woodworking for less than a millimeter or 1/64th. Depending on geographic location, it would either be a “smidgen” or a “hair”. Lol

-- miles125, Alabama.."Architecture is frozen music""

Miles, you’re absolutlely right. But I think we’re talking about 2 different things.

For planning purposes, we need to be very precise. The example you give is a good one. But once you do the math, say you want to cut 45 pieces of wood that will fill a 62” space. The math tells you that each piece should be 1.37777777777 inches long. But in real life, if you manage to cut all 45 pieces within 1/64th of that figure, you are doing about as good as you can hope to do, in my opinion. Try to put those 45 pieces end to end and have them total 62”. I’ll bet a rusty block plane that you’ll either be a hair short or you’ll have to get out the sandpaper.

So my point was that, for the purpose of measuring and marking a cut line, 1/64th is more than close enough.

-- Charlie M. "Woodworking - patience = firewood"

you can use long ruler diagonally to get better accuracy (the same trick used for spacing dovetails). i have several rulers with 0.5mm markings on them, and i agree with niki – you cant see them or use them – they are just annoying. i find that i have better accuracy trying to mark in the middle of 1mm segment than trying to count the 0.5mm and mark on the right one.

-- The woods are lovely, dark and deep, but I have promises to keep...

I have a Starrett Digital Tape Measure (which I damaged so I haven’t
use it in awhile) – that has inches on the tape but will do metric and
inch/decimal readings. Like everybody here I am accustomed to working
in 1/8” or 1/16” but also since I build guitars I became used to using
a dial caliper which runs in 1000’s of an inch.

Anyhow, the Starrett tape will do all three and it will convert and allow
you to set “zero” points by clicking a button. It wasn’t expensive either -
I just haven’t got ‘round to replacing the broken tape… which I “dubbed” into
a spinning table saw blade a while back.

-- Need help with marketing your business? Look in my profile.

Easy way out Charlie, just use millimetres. LOL

-- Grumpy - "Always look on the bright side of life"- Monty Python

Ya know, Grumpy, I’d be perfectly willing to go along with the whole metric deal if we could just change everything and not be stuck dealing with two systems.

-- Charlie M. "Woodworking - patience = firewood"

What Charlie said!

Bob

-- A mind, like a home, is furnished by its owner

Charlie, The conversion part is not too bad. It’s the thinking in metric thats the hardest. Like thinking gas per litre as against per gallon.

-- Grumpy - "Always look on the bright side of life"- Monty Python

Thanks Charlie, I can use this. Terry

-- Terry Roswell, L.A. (Lower Alabama) "Life is what happens to you when you are making other plans."

Great chart, thanks – I love Excel for this stuff. I have a set of calipers that do inches and MM and I’d be lost without them. I use them all the time when trying to find a fractional drill bit that’s ‘close enough’ for my pen tubes!

-- Tim D. - Woodstock, GA

Wow charlie this is great!!! I have needed something like this for a very long time. Great! it is going right up to my shop!
PEACE!!!
I not only can use this. I will use this!

-- Allison, Northeastern Ca. Remember, Amateurs built the Ark. Professionals built the Titanic!

Glad to have been of service!

-- Charlie M. "Woodworking - patience = firewood"

Thank you so much!!!! I’ve been working on a sketchup plan for a kayak I’m hoping to build soon, and all the plan dimensions are in mm’s, this is a HUGE help.

Thanks!

-- Ryno