# Table Saw Measuring Tape



## thepres560 (Sep 17, 2017)

I have a Ridgid 10" table saw, and the measurements under the fence indicator are accurate around 18 inches and higher. However, under that they are hit and miss. Example, I have to set the fence to about 1/32-1/16th past the 4 1/2" reading, to get an actual 4 1/2" width from the fence to the blade. The tape measure is dead accurate and being that it is measuring good at the upper widths, I don't think it needs the indicator adjusted. What else could be causing this to happen?!? Thank you! 

Sent from my SM-N950U using Tapatalk


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## epicfail48 (Mar 27, 2014)

The tape measure isnt accurate. Theres nothing mechanical that could cause distances to be bang on at 18" but off by 1/4" at 4 inches, not unless part of moving the fence entails smacking the distance indicator while you move the fence. Id replace the tape measure, or go whole-hog and throw on a DRO. The Wixy unit is pretty awesome


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## GeorgeC (Jul 30, 2008)

I have never even considered using that "built in" tape measure. I physically measure each change of setup.

George


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## Tool Agnostic (Aug 13, 2017)

In case it matters, I use the built-in tape on my Bosch REAXX table saw. I simply set the fence and cut. It is very accurate. Cuts match the measurements of the digital caliper.

The built-in tape was perfectly calibrated to the Bosch blade that came installed in the saw. I had to recalibrate the line when I swapped the blade for a Forrest Woodworker II blade. The recalibration is accurate. I can't see any measurement variance on cuts within the precision and accuracy of the tape itself.


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## woodnthings (Jan 24, 2009)

*simple fix .... replace the tape*

Amazon has all sorts of replacement tapes such as this:

https://www.amazon.com/Kreg-KMS7724...05658174&sr=8-3&keywords=table+saw+fence+tape

If you like using the tape, since it's very convenient and there is no tape measure laying around to deal with when using it, just get a new tape. Once your set up is calibrated, there's no need to measure until you change the blade thickness. I use my tape on the Unifence, but I often "cut to fit" when making projects, to eliminate measuring as much as possible. :| 

It's more about a style of working than which method is best. It's easy to verify your set up by choosing a dimension ... say 4", making a cut then measuring the result.:nerd2:


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## Jim Frye (Aug 24, 2016)

I only use the rail tape for minor fractional changes (less than 1/8"). I always measure from the outside blade tooth to the fence for setups. I got into the habit early on. Since the rails on my saw are moveable some 30" left or right, it would be a waste of time "zeroing" the tape each time. Much more accurate to measure blade to fence with the same measuring device each time for repeatable accuracy.


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## FrankC (Aug 24, 2012)

I would double check that tape strip, what you are describing is physically impossible, in this day and age quality control is a bit lax in some situations.


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## woodnthings (Jan 24, 2009)

*old school VS analog VS digital ... the wnner is ?*

Old School:


GeorgeC said:


> I have never even considered using that "built in" tape measure. I physically measure each change of setup.
> 
> George


Analog:


Tool Agnostic said:


> In case it matters, I use the built-in tape on my Bosch REAXX table saw. I simply set the fence and cut. It is very accurate. Cuts match the measurements of the digital caliper.
> 
> The built-in tape was perfectly calibrated to the Bosch blade that came installed in the saw. I had to recalibrate the line when I swapped the blade for a Forrest Woodworker II blade. The recalibration is accurate. I can't see any measurement variance on cuts within the precision and accuracy of the tape itself.



Digital:


epicfail48 said:


> The tape measure isnt accurate. Theres nothing mechanical that could cause distances to be bang on at 18" but off by 1/4" at 4 inches, not unless part of moving the fence entails smacking the distance indicator while you move the fence. Id replace the tape measure, or go whole-hog and throw on a DRO. (Digital Read Out) The Wixy unit is pretty awesome


At some point you have to trust your measuring method and the instrument/device used to measure. :smile3: The new DROs have to be calibrated, just like a tape used on the fence which is analog. Once that's done and verified, that's all you need to do. I don't see cabinet or production shops going back to tape measures on their sliding table panel saws, it ain't gonna happen. The DROs are cheap enough now to put them on any table saw IF that's your style of working. I can split a 1/32" on my Unifence with the sticky tape if I'm working that close.

If you use a tape measure, which is not as accurate for measuring lengths compared to a steel rule, then you must use the same tape measure for all your dimensions to eliminate errors in the tape itself and visual ones from reading the wrong numbers and from sighting down the work at different angles. 

It also depends on the scale of your projects. Large casework can be off by 1/32" without "epic failure" and when working large panels over 24" your saw must also be accurately setup or all your precise measuring is for naught. When fitting small boxes and lids you must be dead on or it won't fit and often measuring is not the answer, just eyeball the amount and trail and error will make it fit.
OK, that takes some experience to get it right. :smile3:


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## canarywood1 (Jun 9, 2016)

I've always used the tape on my Biesemeyer fence, accurate down to a gnats hair.


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## gmercer_48083 (Apr 9, 2016)

Wow! that doesn't say much for Ridgid! Replace the tape...I would recommend a starrett brand.


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## Pineknot_86 (Feb 19, 2016)

GeorgeC said:


> I have never even considered using that "built in" tape measure. I physically measure each change of setup.
> 
> George


Me, too. It might be a bit accurate to a certain point but I don't trust it. I use a good quality tape measure. For anything under 12 inches, I use a Brown & Sharp ruler/square combination.


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## FrankC (Aug 24, 2012)

A tape is a tape, whether it is rolled in a case or laid along a rail, one should work as well as the other, in fact if the built in tape has a magnifier on the indicator it should be even better for some of our old eyes.:laugh2:


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## epicfail48 (Mar 27, 2014)

FrankC said:


> A tape is a tape, whether it is rolled in a case or laid along a rail, one should work as well as the other, in fact if the built in tape has a magnifier on the indicator it should be even better for some of our old eyes.:laugh2:


You've never used a Harbor Freight tape measure...


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## FrankC (Aug 24, 2012)

Once you have established the accuracy of a scale or DRO on a machine you are now working with absolute numbers, where working with a rule or tape you are basically transferring dimensions. 
The problem usually arises when you use a combination of the two and the devices are not calibrated to give identical readings.


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## woodnthings (Jan 24, 2009)

*here we go again....*



FrankC said:


> A tape is a tape, whether it is rolled in a case or laid along a rail, one should work as well as the other, in fact if the built in tape has a magnifier on the indicator it should be even better for some of our old eyes.:laugh2:





epicfail48 said:


> You've never used a Harbor Freight tape measure...


Harbor Freights inches are cheaper than Starretts inches, BUT they are still inches. They could be calf knuckles as long as you use the same device for your measurements on the project it won't matter UNLESS you are working from plans. Woodworking doesn't require measurements to the .001 of an inch and if your measurements must be that close, a tape measure is the wrong tool, Harbor Freight or any one's. 

Sometimes a tactile fit is what you want anyway, like a tenon in a mortise or a panel in a dado. It either fits or it don't. Sneaking up on the fit is better than measuring because of limitations in the measuring device, it's part of the joy of woodworking. :smile3:


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## subroc (Jan 3, 2015)

If I was the OP faced with that problem, I would verify 2 things, the stability of the fence clamping and the tape. The tape is the easiest thing. I would take the best scale I had, a Starret would be ideal, but the metal scale from your combination square would work as well and check it to the scale on the saw. Clearly you have to trust something so, in my view, trusting the metal scale is a better choice. It is either right on or not. I would verify the fence is locking up. It is or it is not.

I would check one final thing. Parallax view. Am I looking at the scale to glass exactly the same every time?


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## woodnthings (Jan 24, 2009)

*The only mesausrement that matters ....*



subroc said:


> If I was the OP faced with that problem, I would verify 2 things, the stability of the fence clamping and the tape. The tape is the easiest thing. I would take the best scale I had, a Starret would be ideal,* but the metal scale from your combination square would work as well and check it to the scale on the saw.* Clearly you have to trust something so, in my view, trusting the metal scale is a better choice. It is either right on or not. I would verify the fence is locking up. It is or it is not.
> 
> I would check one final thing. Parallax view. Am I looking at the scale to glass exactly the same every time?


What you really want is for your tape scale to read the same as the finished piece. No need to measure the inches on the tape, just that the indicator must read the correct number and be the same as the ripped piece, that's all that matters.


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## epicfail48 (Mar 27, 2014)

woodnthings said:


> Harbor Freights inches are cheaper than Starretts inches, BUT they are still inches. They could be calf knuckles as long as you use the same device for your measurements on the project it won't matter UNLESS you are working from plans. Woodworking doesn't require measurements to the .001 of an inch and if your measurements must be that close, a tape measure is the wrong tool, Harbor Freight or any one's.
> 
> Sometimes a tactile fit is what you want anyway, like a tenon in a mortise or a panel in a dado. It either fits or it don't. Sneaking up on the fit is better than measuring because of limitations in the measuring device, it's part of the joy of woodworking. :smile3:


Nah, they SAY they're inches. Whether or not they are actually inches is an entirely different matter. Its not all about measuring to .001 either, you see errors at larger scales than that. I've taken cheap tape measures (HF, dollar stores, bargain bins at Ace), lined them all up next to each other and watched as the marking on absolutely none of them matched up with each other. Which ones a true inch? Should you just go with the first one you grab? Well, if you take the first one you grabbed doesn't even measure up to itself when you fold it back on itself and line up 2 'inches'!

Really, the original post in this thread kinda points out how variable measuring devices can be. Yes, relative measuring is certainly more handy in woodworking, and you don't need a perfectly calibrated scale to do that, but if you need something cut at an inch, you need to actually be able to measure an inch. Scale won't help if an inch on it is actually 1 1/16 of an inch. 

And no, I'm not claiming that you need to go out and but a precision Starette, just a decently reputable brand. Stanley and Komeleon are my favorites. Just don't be surprised if that tape measure you got for free with a coupon measures in a unit that doesn't corrospobg to any known unit of measure


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## woodnthings (Jan 24, 2009)

*line 'em up and take a photo for us ....*



woodnthings said:


> What you really want is for your tape scale to read the same as the finished piece. No need to measure the inches on the tape, just that the indicator must read the correct number and be the same as the ripped piece, that's all that matters.


I don't care if they are all different, it won't matter unless you are them all on your project. Stick to one measuring stick and you'll be fine. If the tape on the OP's rail is so far off, then as he was adviced, he should replace it. All this other discussion is just talking amongst ourselves, it won't make any difference since he's not using a tape measure anyway, it's a flat steel sticky backed tape with no hook to confuse matters.


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## FrankC (Aug 24, 2012)

Throw those rules and tape measures away and use your iPhone:

https://9to5mac.com/2017/06/26/arkit-ar-tape-measure-iphone/


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## allpurpose (Mar 24, 2016)

I always think my table saw tape is going to be wrong, but it never is and I check it from various distances pretty regular..Must be my eyes are the same age as the rest of my body..I don't know how I managed that this long.


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