# not all inches are equal



## paduke (Mar 28, 2010)

I use both tapes and a foldable stick rule in my shop. today I bought a new tape and as I was selecting it I thought I should share how I choose a tape' At the store I compare them to the stick rules on the hook and butt measurements. I use a zero end stainless steel rule and to verify my tapes Just thought I would share


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## Artemix (Aug 10, 2014)

Why use inches?, use the metric system like the cool kids 

Just kidding, yeah, the thing about those tapes is that they are not meant for precision. But still, that's pretty bad, unless the curve of the tape is tricky.


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## paduke (Mar 28, 2010)

Its what I grew up with but for you not all cm are equal


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## RainMan 2.0 (May 6, 2014)

Bill thanks for the tip . Such an easy solution , yet not something I would think of doing


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## Dmeadows (Jun 28, 2011)

That is why it is important to use the same tape throughout a project. Or better yet as much as possible... NO tape measure. Really fun when it is your table saw scale that's off! I knew there was a reason I like the Incra:lol:


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## Artemix (Aug 10, 2014)

Everyone talks good things about Incra, I wonder if there is a way to build a home-made version.


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## Stick486 (Jan 4, 2013)

look to where the tape was manufactured....
*SNARK!!!!!*


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## DaninVan (Jan 1, 2012)

Whadda ya want for $3.49... 
But what Duane said, +1.
Tapes were never intended for extreme accuracy; if you're framing or drywalling, nothing beats them.


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## TwoSkies57 (Feb 23, 2009)

+1

I started doing this years ago and found that it made one heck of a difference when it came time to put things together. 



Dmeadows said:


> That is why it is important to use the same tape throughout a project. Or better yet as much as possible... NO tape measure. Really fun when it is your table saw scale that's off! I knew there was a reason I like the Incra:lol:


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## RainMan 2.0 (May 6, 2014)

TwoSkies57 said:


> +1
> 
> I started doing this years ago and found that it made one heck of a difference when it came time to put things together.


Geez now I have to check all my tapes just to be sure


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## TwoSkies57 (Feb 23, 2009)

Hey Rick..

I recall reading about this and something that was called accumulated error. I remember thinking, an inch is an inch, how much difference can there be. To my surprise, there was a visual difference between several of the tapes that I have. Even between several of the metal rules I have. I used a Bridge City Tools metal rule as my 'standard'. I have a cheap craftsman 12' tape that was dead on, a 30' craftsman tape (I think that is what it was) that was out by 1/32" at 2'. I have several fast cap tapes that are pretty darn accurate. Anymore I use my Incra and woodpecker rules whenever I can. I still use that 12" craftsman tape as well....


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## schnewj (Nov 18, 2013)

Stick486 said:


> look to where the tape was manufactured....
> *SNARK!!!!!*


Oppps! There is the dreaded 'a'. It must be sarcasm!


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## Stick486 (Jan 4, 2013)

schnewj said:


> oppps! There is the dreaded 'a'. It must be sarcasm!


yep....


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## schnewj (Nov 18, 2013)

TwoSkies57 said:


> Hey Rick..
> 
> I recall reading about this and something that was called accumulated error. I remember thinking, an inch is an inch, how much difference can there be. To my surprise, there was a visual difference between several of the tapes that I have. Even between several of the metal rules I have. I used a Bridge City Tools metal rule as my 'standard'. I have a cheap craftsman 12' tape that was dead on, a 30' craftsman tape (I think that is what it was) that was out by 1/32" at 2'. I have several fast cap tapes that are pretty darn accurate. Anymore I use my Incra and woodpecker rules whenever I can. I still use that 12" craftsman tape as well....


I don't use tapes for anything under 18". I have a couple of hook rules that are pretty darn close. Besides, it is hard to find a right handed tape. Most folks don't know that you can get right and left handed tapes. Most places sell "left handed" tapes. For a right handed person holding the tape in their left hand the numbers are upside down. The right handed tape reads right to left when held in the left hand. In other words, the numbers are right side up. which makes it easier for a right handed person to read and mark.

Bill


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## TwoSkies57 (Feb 23, 2009)

I hear ya Bill... for rough cuts, I'll use a tape... for finish cuts under 24"s, I use a woodpeckers aluminum rule or Incra rules. Damn, I go thru the .5mm pencils...*L*


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## IC31 (Nov 16, 2012)

I found out about 20 years ago that all inches were not the same world wide. We were installing a power plant outside of Seoul, Korea and our first foundation wasn't just a few sixteenths off, but many inches. We finally traced it to the local contractor that supplied tape measures to his workers. All of our foundation drawings, being from a big American company were done in US Standard Units, not in metric units. The tapes had not four quarter inch marks/inch but five which meant that every 12 inches per their tape would be actually 15 inches. That mistake cost a bunch of time as well as dollars and Korean won.

If I'm building something with a tape, I use the same two that are identical as a couple others don't match these inch for inch


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## Stick486 (Jan 4, 2013)

so why not validate the accuracy of the tape before it leaves the store and drive on...


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## Stick486 (Jan 4, 2013)

schnewj said:


> Oppps! There is the dreaded 'a'. It must be sarcasm!


...


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## DaninVan (Jan 1, 2012)

Error can creep in over time by allowing your tape to auto-retract until the hook bangs into the case, Eventually it'll elongate the mounting holes on the tape itself, or on the hook, or both.
Use your fingers to slow the return, but watch out for razor cuts from the sliding edges!


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## paduke (Mar 28, 2010)

Stick486 said:


> so why not validate the accuracy of the tape before it leaves the store and drive on...


Thats what i did in OP


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## 64 ford (Apr 21, 2013)

What's all those small marks?! Seriously, what Dan said is the culprit in a lot of cases.
Dennis


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## rwl7532 (Sep 8, 2011)

Reminds me of how I selected a small 5" plastic level. I grabbed a half dozen from the bin. Then I grabbed the longest and most expensive level that was on display.
I placed the long level on the floor. Dead level.
Then one by one I placed the cheap plastic levels on top of that level.
I took the one that gave the dead level reading and put the others back.


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## Herb Stoops (Aug 28, 2012)

I must have 20 tapes in the shop. one or two by every machine and several scattered around the benches and shelves. Everyplace I go I have a tape to grab. Never checked any of them for accuracy , never had a problem either. My only problem was I could never find a tape when I needed it. I use steel rulers too at times, but most everything is done with tapes. I have adapted to not being an super accuracy guy and worry about all those tiny marks that I can't see anyway. 

Herb


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## JOAT (Apr 9, 2010)

Old news they are not all exactly the same. So what? I have tape measures everywhere, in my Jeep, bathroom, bedroom, jacket pockets, and so on. Very handy if you want to know how long something is, or are figuring out a new project. I've got free tape measures, cheap ones, high quality ones, and it does not mean a thing to me that they are not all precisely the same.

You see, the trick is, use the same measure, whether yardstick or tape measure, on the project you are working on. Then all the measurements are exact. 

K.i.S.S. is the answer - Keep It Simple Stupid.


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## firstmuller (Aug 28, 2014)

Very good info but how do you check a square at the store?
Allen


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## MT Stringer (Aug 15, 2012)

The udder day, I got a free 1"x25' tape at Harbor Freight after making a purchase. I decided to check it after I got home. At 24 inches, it was almost dead on, but at 48 inches, it was off by an 1/8th inch. UGH! Well, it was free. 

It is larger than the others I have so it will be used for measuring 2x4's.


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## Nickp (Dec 4, 2012)

schnewj said:


> I don't use tapes for anything under 18". I have a couple of hook rules that are pretty darn close. Besides, it is hard to find a right handed tape. Most folks don't know that you can get right and left handed tapes. Most places sell "left handed" tapes. For a right handed person holding the tape in their left hand the numbers are upside down. The right handed tape reads right to left when held in the left hand. In other words, the numbers are right side up. which makes it easier for a right handed person to read and mark.
> 
> Bill


Oh, no...does this mean I have to switch tapes when I measure right to left versus left to right...? 
It sounds like the way nails are packaged...some are no good because the head is on the wrong side for the wall I'm working on...I save those nails for work on the opposite side... :moil:

Nick


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## ksidwy (Jul 13, 2013)

The same happens to cm too! Now I use only one till the end of project!
Sid


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## Garyk (Dec 29, 2011)

+1 for Duane. Sometimes tapes made by the same source are not the equal. Folding rules get sloppy in the joints with age. I prefer steel rules and you get what you pay for. Stay away from the cheap stuff. Incra products are highly accurate (IMHO). The Woodpecker products are good too. Put all but one rule away when you start a project. That will force you to use the same device throughout the project.


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## Ghidrah (Oct 21, 2008)

Stupid question, how do you know the item used to gauge is any more correct than what is being tested?

As for levels, the only way to test the accuracy of a level is to set it down and level it out, once it reads level rotate it and check, (still level), flip it and check, (still level) finally rotate it and check. If the bubble remains within the marks in all 4 positions it is accurate enough for any construction project.

When I did a sidewall job the 1st thing I did was set my transit up, (guaranteed +/- 1/4" at 100 yards). Set it at a corner that gave 2 sides of a house then checked windows, doors starter course and frieze. I never had to futz a course to make it line up around a corner. I did discover, (excluding really old houses) many framers, aren't consistent when installing windows.

For the most part accuracy is relative, when they come out with a metal ruler based on multiples of whatever atoms and burned with a pico or femto laser I'm a belly up to the counter for one.


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## schnewj (Nov 18, 2013)

Nickp said:


> Oh, no...does this mean I have to switch tapes when I measure right to left versus left to right...?
> It sounds like the way nails are packaged...some are no good because the head is on the wrong side for the wall I'm working on...I save those nails for work on the opposite side... :moil:
> 
> Nick


I can't believe it took so long for someone to react! 

Nick, your wrong about the nails...they don't go on the other side of the wall. Everyone knows that you use them on the opposite wall...


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## Herb Stoops (Aug 28, 2012)

It is all academic ,the old craftsman had a string with marks on it or a stick with marks on it. and a foot was the length of the Kings foot. Look at all the wonderful works still standing after all those thousands of years.

Herb


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## MT Stringer (Aug 15, 2012)

UGH! Does fairly close count? The board is 24 inches long according to the folding ruler. The others are kinda close. So confusing. 

I use the board to calibrate the Kreg Measuring system on the miter saw station.


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## Dmeadows (Jun 28, 2011)

Herb Stoops said:


> . I have adapted to not being an super accuracy guy and worry about all those tiny marks that I can't see anyway.
> 
> Herb


You didn't by any chance do a lot of work for the previous owner of my house?:lol:
Come to think of it, not sure they even measured anything!

Oh, and I understand all to well about seeing those little marks!


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## Ghidrah (Oct 21, 2008)

I use very bright lights and mag glasses. 2nd I use a machinist square to square my TS blade to the table. 3rd I use my Incra 3000 to dupe material and I check it against the TS blade regular. Those 3 things help me keep my joints square, what I do need is one of those digital angle thingies for the TS miter.


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## paduke (Mar 28, 2010)

woodsmith sale on zero end steel ruler http://www.woodsmith.com/rules.php?...dsmithTips&utm_medium=email&utm_campaign=8992


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## RÖENTGEEP (Feb 18, 2014)

paduke said:


> woodsmith sale on zero end steel ruler Collectible Rules - Woodsmith Magazine


I just bought those rules and I like them, I think the only thing that is not in those rules are a small scale at the end of them, for instance to measure some router bits ratio.


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## Herb Stoops (Aug 28, 2012)

MT Stringer said:


> UGH! Does fairly close count? The board is 24 inches long according to the folding ruler. The others are kinda close. So confusing.
> 
> I use the board to calibrate the Kreg Measuring system on the miter saw station.


All those look good to me. All you accuracy guys should be metal workers....Sheeeeesh.

Look sometime for what the tolerances in woodworking is, It is not .0001"

Herb


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## Dmeadows (Jun 28, 2011)

Herb, I checked 10 different(9 different brands) rules yesterday, including the tape on my tablesaw. At 42" they were all within about 1/32". I think you are right... close enough for most things.

That said, a couple of thousandth can make the difference between a good fitting box joint and one that's too tight to put together! I agree that ten thousandths are totally silly for woodworking... breath on it an wood moves way more than that!


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## Stick486 (Jan 4, 2013)

Herb Stoops said:


> All those look good to me. All you accuracy guys should be metal workers....Sheeeeesh.
> 
> Look sometime for what the tolerances in woodworking is, It is not .0001"
> 
> Herb


checked a bunch of them too....
all within 1/32 or less...
except for the imported free-bees... they were way off... up to 5/16" in 48"....
lets get on with the project....


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## Herb Stoops (Aug 28, 2012)

Dmeadows said:


> You didn't by any chance do a lot of work for the previous owner of my house?:lol:
> Come to think of it, not sure they even measured anything!
> 
> Oh, and I understand all to well about seeing those little marks!


I worked 40 years in the trades and almost half in residential, the rest in commercial. The residential had larger tolerances than the commercial. In housing you use hand levels to plumb and level things, with tripod levels and transits only for certain tasks.

in commercial work especially high rise construction you use transits and plumb bobs, tripod levels exclusively, even inside to set level lines all way around the interior rooms. Later on they went with lasers to do all that. 

But even lasers have tolerances,depending on the size of the red dot.


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## Dmeadows (Jun 28, 2011)

I have used transits, plumb bobs, ans tripod levels, all for residential. Never did commercial. I would hope that high rise buildings are built a bit more accurately than some of the house I've seen, Herb.

I agree with you that the accuracy required depends a lot on what your building.

Well, as Stick said, back to the project. Wish he'd of said which one, though


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## Stick486 (Jan 4, 2013)

Dmeadows said:


> Well, as Stick said, back to the project. Wish he'd of said which one, though


just finished up a nap project...
think I'll give the Elk burger project a go now....


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## DaninVan (Jan 1, 2012)

There's a Project?! Man, nobody tells me anything...on the other hand I guess I can claim plausible deniability.
(Furthermore, in addition to which, I definitely didn't put my name down on any more damned volunteer lists!)


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## Stick486 (Jan 4, 2013)

DaninVan said:


> There's a Project?! Man, nobody tells me anything...on the other hand I guess I can claim plausible deniability.
> (Furthermore, in addition to which, I definitely didn't put my name down on any more damned volunteer lists!)


need to check your in box more often Dan...
let me finish this Elk burger project 1st and then we can move on to the next one....


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## Stick486 (Jan 4, 2013)

DaninVan said:


> There's a Project?! Man, nobody tells me anything...on the other hand I guess I can claim plausible deniability.
> (Furthermore, in addition to which, I definitely didn't put my name down on any more damned volunteer lists!)


Gonna go get deeply involved in another nap project... 

hurry...


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## schnewj (Nov 18, 2013)

Stick486 said:


> Gonna go get deeply involved in another nap project...
> 
> hurry...


Stick,

I'm pretty good at nap projects, but not so good at Elk burger projects. I would be willing to join you and help with the project if you want.

Bill


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## Nickp (Dec 4, 2012)

schnewj said:


> Stick,
> 
> I'm pretty good at nap projects, but not so good at Elk burger projects. I would be willing to join you and help with the project if you want.
> 
> Bill


I'm not saying a word...:fie:


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## schnewj (Nov 18, 2013)

Nickp said:


> I'm not saying a word...:fie:


Opps! Guess I should have specified the Elk Burger project...


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## Stick486 (Jan 4, 2013)

schnewj said:


> Opps! Guess I should have specified the Elk Burger project...


*WHEW!!!!*
ya had me worried there for a bit...

I regret to inform you that you were too slow and the ''Elk Burger Project" has been completed... 
as a result of your tardiness I was forced to "carry the load" and complete your part of the project by myself.....
to included the coleslaw sub-project....


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## Phil P (Jul 25, 2010)

Herb Stoops said:


> In housing you use hand levels to plumb and level things, with tripod levels and transits only for certain tasks.
> 
> in commercial work especially high rise construction you use transits and plumb bobs, tripod levels exclusively, even inside to set level lines all way around the interior rooms. Later on they went with lasers to do all that.
> 
> But even lasers have tolerances,depending on the size of the red dot.


Hi Al

They certainly do. For really accurate work (such as setting-out floor levels) over, say 60 to 80ft runs I still use a dumpy level (transit) - the lasers only come out when we get down to the "inaccurate" stuff such as suspended M/F ceilings :lol: because they run out too far over distances. On some jons it doesn't matter what we do, when the "spreads" (wet plasterers) have been over them the walls will never be the same.......

On the original question of tapes I've always had the practice of using a single "master" tape for any project. Any tape you use to measure on site MUST be used back at the shop to check the cuts, etc. so it makes sense for the foreman to hold the master or reference tape. A lot of the time, though, I still depend on either making a carpenters rod (story pole) or a physical template (for stuff like granite countertops) from which actual dimensions get transferred. If someone else is making for me I'm often left hoping that they have enough experience to include a bit of scribing allowance, if the design permits it. Not all modern bench joiners have such "nouse" these days - it comes from the fact that they no longer go out to site to install anything any longer, so they just don't know what we need, and often can't be bothered to listen - until they get me shouting down the phone at 'em!

Regards

Phil


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## darsev (Feb 3, 2012)

Phil P said:


> If someone else is making for me I'm often left hoping that they have enough experience to include a bit of scribing allowance, if the design permits it. Not all modern bench joiners have such "nouse" these days - it comes from the fact that they no longer go out to site to install anything any longer, so they just don't know what we need, and often can't be bothered to listen - until they get me shouting down the phone at 'em!
> 
> Regards
> 
> Phil


Phil,

A few years back I was working in a cabinet making shop, and all I can say is that we can only cut to the numbers given to us because that is all that we have. The table saw had a digital fence and the CNC's would cut a sheet up in roughly 10 minutes. With the time we had
you had to rely on the calibration on those things, which was mostly pretty good. However if the Vacuum hold down on the CNC wasn't working... well some of the results belonged to the Museum of Modern Art.

We did get stuff ups, but usually that was from the guys who did the original measure up or drawings. In one case, a bloke went out to measure up some units. Did the first 2 and found they were the same, so he assumed the rest were identical. Wrong assumption.

Darryl


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