Incra flex ruler 1/32 too long?

ear3

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I have no idea why I didn't check this when I first got them, or just didn;t notice, but I just realized that both my 6" and my 18" Incra flex rulers measure 1/32 greater than the actual value.  I double checked it against multiple tape measures and a woodpeckers ruler.  It doesn't really affect the work since I almost always use it to mark things relationally/in pairs, like facing mortises for the Domino. But it did just mess  up a dado I was routing that had to be offset exactly 5/8 from the edge (not 21/32).  Wondering if anyone else has run into this issue with those rulers?

Looking forward to receiving my Woodpeckers saddle squares even more now. 
 
Bizarre. Mine has an indentation in the centre to account for a pencil line but is definitely zeroed correctly.
 
I just measured my Incra 12 inch ruler against a Starret 72 inch ruler. They were within the width of the marking lines which is very fine on these rulers.

However, when I measured my Woodpecker 50 inch hook rule against the Starret, the Woodpecker rule was short by about 1/64 th inch at 48 inches (I was using a camera phone and enlarging the photos. There might be a bit of error of course with this method.)  When I measured the new Woodpecker story stick at 30 inches, the Woodpecker and the Starret were basically dead on.

Comparing the Woodpecker 50 inch hook rule and a 32 inch story stick, the hook rule is visibly short at 30 inches, the inch mark of the hook rule is definitely to the inside of the corresponding mark on the story stick. These comparisons were made using a small magnifying glass so camera alignment error was not an issue.

Knowing what to trust as a reference tool can be a difficult issue.

 
I also had a problem with the Woodpeckers 50" woodworking rule and hook stop.  I compared it to my Woodpeckers 32" T- square and my Woodpeckers 36" woodworking rule and it was starting to go off at around 20" and the differences got larger the further out from there.  I sent them an email with a photo of all 3 of their products lined up - showing the obvious error. They were pretty good about replacing the 50" rule for me, but to this day I still have doubts in the back of my mind regarding the accuracy of their products ( of which, I admittedly have many). Pretty disturbing considering they are supposed to be using state of the art CNC equipment.
 
Has this problem showed up on anyones metric INCRA rules, or just their inch divided rules?

If the problem shows up on both inch and metric rules than Incras laser could be allowed to go out of calibration.

Another possible source if error would be if the steel stock used for the rules isn't stored in a climate controlled area, the steel could expand or shrink if it wasn't at a standard 20 degrees celcius when cut.

The other problem I can think could cause the error if it only shows up on inch divided rules, would be if the CNC laser doesn't use enough decimal places when converting dimensions from the metric standards to inch dimensions. I recall seeing the conversion rate for thread standards from metric to inch dimensions and the lack of decimal spaces looked like it could cause issues with precision over longer distances especially when the dimensions are a yard or more.

 
Egad!  Now I'm going to have go back and obsessively check all my woodpeckers rulers. 

Steve-Rice said:
I also had a problem with the Woodpeckers 50" woodworking rule and hook stop.  I compared it to my Woodpeckers 32" T- square and my Woodpeckers 36" woodworking rule and it was starting to go off at around 20" and the differences got larger the further out from there.  I sent them an email with a photo of all 3 of their products lined up - showing the obvious error. They were pretty good about replacing the 50" rule for me, but to this day I still have doubts in the back of my mind regarding the accuracy of their products ( of which, I admittedly have many). Pretty disturbing considering they are supposed to be using state of the art CNC equipment.
 
Exactly. To be fair to Woodpecker, 1/64 inch off at 48 inches is a pretty small error. I think I probably checked my 50 inch hook rule when I received it and decided it was accurate enough. If I had wanted to get it replaced, as noted above, I do not doubt that they would have replaced it. Once again, we are talking woodworking and not machining metal.

On the upside, the newer story stick does look to be dead on. So over time they have been getting better.

I may be putting the 96 inch story stick (new product not a one time tool) to the test in building a 4 bay sysport with edge banded plywood. The tricky part is the base and top need to be 4x 17 inches (bays) + 5 x 23/32s + thickness of edge banding. I may just use 1/8 thick banding on one end and 3/16 isn on the other and rout the excess off. Or I could edge band one end only and then use templates to find the exact length and cut a strip of banding to fit. Or...
 
Edward A Reno III said:
Egad!  Now I'm going to have go back and obsessively check all my woodpeckers rulers. 

[member=37411]Edward A Reno III[/member] I wouldn't. You will drive yourself crazy!. I found that, as I get older, my eyesight and the angle at which you look at all these rulers make a slight difference. For cuts which require multiple pieces with the same length, width, or thickness, I just make sure I cut them all at once and with a stop or with the same planer thickness. Once differences get less than 1/64", it's difficult to tell there is a difference. It's more important that I get crosscuts square and ripped widths consistently the same width. I have sometimes noticed that, with the Incra flexible rulers, especially on measurements with the T-Rules, it's important to make sure that the ruler is flat on the surface or sometimes the measurement can be very slightly off. Even that hasn't usually made a difference.
 
I'm a little bit confused and I need some help.  This thread started out about an Incra tool; Incra is headquartered in Dallas, and I believe most of their stuff is manufactured on site in Dallas.  The discussion then moved to Woodpeckers, which are headquartered in/near Cleveland, OH, and their manufacturing is performed there.  I don't believe the 2 are the same.  So, are we sorting out that both may have issues with their NIST calibrations?
 
After Starrett, woodpeckers is generally considered the gold standard for accuracy. Every shop needs a fixed reference point to settle any discrepancies over measurements.

[member=19734]grbmds[/member] Thanks for the sanity check.

DrD said:
I'm a little bit confused and I need some help.  This thread started out about an Incra tool; Incra is headquartered in Dallas, and I believe most of their stuff is manufactured on site in Dallas.  The discussion then moved to Woodpeckers, which are headquartered in/near Cleveland, OH, and their manufacturing is performed there.  I don't believe the 2 are the same.  So, are we sorting out that both may have issues with their NIST calibrations?
 
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