stanley tape measure accuracy

[Bill Holt]

In another life I worked as a trim carpenter with a good friend.  Most mornings we compared our tapes and adjusted one to the other.  Every time a tape is dropped it should be double checked and the metal tab adjusted if necessary.  I have three tape measures, even though I have adjusted the three tabs so they give the same measurement, I only use one during a build.

Side note:  Now that it is a chore to retrieve items from the floor, I don't drop my tape way down there (as often).

[robert146]

Tape measures make me nervous. I grew up using my father's six foot folding ruler and still use one for everything six feet or less. I never thought to check it from time to time, but I probably should. On the other hand, since it is all I use, any error is constant (I think).

The suggestion to use the same tape measure throughout a project makes a lot of sense. I never gave it a thought and have different ones scattered around the shop for rough measuring. Now I'm gong to check them all and see how much they differ. At least it will satisfy my newly aroused curiosity.

R.

[CLETUS]

In another life I worked as a trim carpenter with a good friend.  Most mornings we compared our tapes and adjusted one to the other.

Yep, if you're only using 1 tape there isn't a problem. 2 tapes, you need to check them. I've seen more than 1 tape measure go flying through the air!

[hbmcc]

Measure from both ends...... It's always a match for me.

[Handplanesandmore]

EVERY measuring tape is accurate and correct as long as you stick to the same one. Why would you think your other rulers or tapes are more accurate even if they agreed with each other? Two wrongs do not make a right, remember.

I have several steel rules that are off with each other; same with measuring tapes. The first few inches are fine, but once you compare over 6" or 10" etc, they are off. If you use a tablesaw, I don't think most of your tapes or rulers would match the scale there. The solution? If your tablesaw tape is used to set the cuts, use the tablesaw scale for all other cuts. If you set the fence with a measuring tape, use the measuring tape only for all other cuts.

There is no need to check your tape at all, as long as you stick to it. The industrial jobsite story of people checking their tapes at the beginning of their days is just that -- a story. During my time as a project manager of a construction business overseeing multiple projects of industrial scale, I had never seen one single tradesperson (carpenters, journeymen, stair installers, window installers, kitchen installers, panel cutters, etc.) do that. There was no reliable or meaningful mechanism to set 80 different tapes to the same standard each day! Heck, we engineers did not check our watches when we said we would have lunch at noon before we departed.

Simon

[Bill_Houghton]

Carpenters build to the nearest 1/16"; cabinetmakers build to the nearest 1/64".*

Stanley's been a carpenter's toolmaker for a long time.
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*The rest of the saying, not as relevant here, is "boatbuilders build to the nearest boat."

[Cecil]

You are expecting too much from a tape measure.  When I need extreme accuracy from a tape measure, I start at the 1" mark and adjust accordingly;

When I need accuracy from a tape measure, I start at the 10" mark.  When I start at the 1" mark, it is often 1" too short.  If I start at the 10" mark, it is generally obvious that what I am reading is grossly off and I don't make the silly adjustment error.  However, when I really need accuracy from a measure, I use a steel rule.  When I need to cut two the same, I use a gauge (previous model) or a story stick.

More recently I have gone to stacking 1-2-3 blocks and brass gauges to arrive at my cut, when it is less than 7".

[Handplanesandmore]

When I need accuracy from a tape measure, I start at the 10" mark.  When I start at the 1" mark, it is often 1" too short.  If I start at the 10" mark, it is generally obvious that what I am reading is grossly off and I don't make the silly adjustment error.  However, when I really need accuracy from a measure, I use a steel rule.  When I need to cut two the same, I use a gauge (previous model) or a story stick.

More recently I have gone to stacking 1-2-3 blocks and brass gauges to arrive at my cut, when it is less than 7".

Haha. The classic 1" too short blunder. Anyone who has not (yet) suffered from that mishap is just lucky and it will catch up on them one day, sooner or later. I stopped using the 1" mark after I had humiliated myself more than once.

For dead-on accuracy, sighting (against a steel rule, etc.) is not reliable and I use a stick and marking knife. Of course, we can always argue we work with wood for which exact measurement is only relative (wood moves). I know some woodworkers talk about tolerance of 0.002" and aren't happy even if the tool/measurement is off by 0.003" from that. 

Simon

[Stwood_]

EVERY measuring tape is accurate and correct as long as you stick to the same one. Why would you think your other rulers or tapes are more accurate even if they agreed with each other? Two wrongs do not make a right, remember.

I have several steel rules that are off with each other; same with measuring tapes. The first few inches are fine, but once you compare over 6" or 10" etc, they are off. If you use a tablesaw, I don't think most of your tapes or rulers would match the scale there. The solution? If your tablesaw tape is used to set the cuts, use the tablesaw scale for all other cuts. If you set the fence with a measuring tape, use the measuring tape only for all other cuts.

There is no need to check your tape at all, as long as you stick to it. The industrial jobsite story of people checking their tapes at the beginning of their days is just that -- a story. During my time as a project manager of a construction business overseeing multiple projects of industrial scale, I had never seen one single tradesperson (carpenters, journeymen, stair installers, window installers, kitchen installers, panel cutters, etc.) do that. There was no reliable or meaningful mechanism to set 80 different tapes to the same standard each day! Heck, we engineers did not check our watches when we said we would have lunch at noon before we departed.

Simon

You sound like an old, out of touch woman. Scolding just to be scolding.


There is reason to check your only tape. Someone calls up wanting a widget measuring 4' 2".
You do the 4'2", and it's off with the customers tape by an 1/8". What to do now........

And the group comparing tapes each/some mornings. I've seen that a few times, different groups.
I myself *do* like to use the same tape during a project, as it's usually clipped on my belt. Why not?

But the used, 4-6 tapes that are scattered about in my shop, and in tools boxes, all match at the 3' mark. Cabinetmakers and staircase builders usually use 36" and down measurements.

[Handplanesandmore]

You sound like an old, out of touch woman. Scolding just to be scolding.


There is reason to check your only tape. Someone calls up wanting a widget measuring 4' 2".
You do the 4'2", and it's off with the customers tape by an 1/8". What to do now........

And the group comparing tapes each/some mornings. I've seen that a few times, different groups.
I myself *do* like to use the same tape during a project, as it's usually clipped on my belt. Why not?

But the used, 4-6 tapes that are scattered about in my shop, and in tools boxes, all match at the 3' mark. Cabinetmakers and staircase builders usually use 36" and down measurements.

Assuming you are not a troll or something, your post made me laugh...come back after you have worked with 6 different teams, using on average 3 three types of measuring instruments each day on their jobs and we can talk. If you work in a small shop, you can calibrate anything you want.

I don't know if you have had any industrial experience managing professionals and tradepersons at the same time. Do you know how we handled contractors from all disciplines? Calibrating their tapes before we started? Give me a break please. If you think the method you use in your shop works and therefore that's how the rest of the world should, I can tell you now, industrial engineers don't work the way you describe. Period.

By the way,  I have worked with many smart and capable women as engineers in case you think they are less capable than people who start their days by comparing their tapes!

Simon