Measuring-Tape Accuracy
Finding an accurate tape measure is a challenge. Ensuring an accurate match between two different tapes is even more challenging. July 11, 2007
Question
We keep running into the same problem - accuracy or precision of measuring tapes used in the shop. We need a reasonable level of accuracy. Most measure tapes have lousy agreement between manufacturers and even between tapes from the same manufacturer. We're looking for a tolerance to within 1/64. 1/32 is causing problems. Am I asking for too much here? Who manufactures decently accurate measuring tools?
Forum Responses
(Cabinetmaking Forum)
From contributor B:
I collect tape measures. I must have most every brand. They're all over the place on accuracy. Drop a good one once and it's toast. I measure from the 1" mark when needed. Our old German/Italian cabinetmaker swears by the folding wooden rules for accuracy. I've had very good luck with the old standard Stanleys. Often I use the back of my cast iron shaper top and hammer them until they're dead on. The Chinese made ones (most if not all of them) have cheap steel tips that bend way too easy. The Stanleys use better steel. I'm sure there's something out there that's as good as a Stanley or better. I'm waiting for a digital, programmable tape measure, so if it's off, you can't reset it. All the technology is there, and so is the need - all we need is a manufacturer to start making one… One that's meant to work and hold up, not some price point piece of junk.
From contributor P:
Craftsman is good. Lifetime warranty, and durable.
From contributor O:
Man... I feel your pain. I am always checking my squares, tapes, etc. I worry that the straight edge I use to align beds on tools or knives isn't really true. I just threw the plastic part of the fence that came with my Powermatic tablesaw in the garbage, and remade it with hard maple laminated with Formica. Doesn't anybody care about what they sell us anymore?
From contributor K:
We ordered some Stanleys from the factory that were calibrated as a set about 10 years ago and I still have mine. I work for a different shop now so I can't compare mine to the rest, but my tape is the most accurate in my shop, at least within 1/64". I don't recall the price we paid but it was not very much more than from the store. By far the best tape I have ever had.
From contributor J:
Contributor K is right on. My Stanleys are very old also and they're better than most of the new trick ones with the pencil sharpeners, etc. I'd rather have beef over tofu any day!
From contributor E:
We have pretty good luck with the Craftsman ones - they're all the same. I don't buy but maybe two or three a year, though. I prefer to use either my four foot rule for most things or a storypole. The storypole is always dead accurate and you don't have to think about it. Just read what you wrote.
From the original questioner:
Thanks for all the fast responses. No doubt, this might be a sore point for a lot of people. Just to keep things on track, I'm not just talking about the accuracy of the terminal end of the tape (which can be put out of adjustment if it's dropped). I'm talking about tapes that line up on the one inch mark and are off as much as 1/32 + at the 20" mark. What's up with that?
From contributor S:
Stanley, and I burn a foot for out to outs under a foot because the numbers read the same. No cutting an inch to remember for my tired brain. Long run inside to inside I mark 10" out of one corner and then come back from the other direction to my mark and add ten. Adding ten is about all the stress my brain can take.
Over-slop in the end or the hook getting bent over needs to be watched out for with any tape, so I will measure critical dimensions by difference (burning an inch or foot). My tapes always come and go in spurts. I can keep one for two years with only the occasional recalibrating, and then I will lose or break six in a month before settling in with the next old favorite.
From contributor N:
I just try to use the same tape for the entire job. I think the practice minimizes the impact of an inaccuracy in the tape. I like the Tofu tapes from FastCap, but the tips bend easily.
From contributor R:
We buy 6 at a time, pull out and match them up (in the store) so they read the same, and change brands or colors so they don't get mixed up with the old.
From contributor L:
We had a machine shop make us a calibrating bar of steel that is attached to the shop wall. It has provisions for both push and pull and gauged at 1", 4/5", 35/36", and one meter. Tapes are used a lot less now than they used to be before everything went CNC.
From contributor V:
Have had the same problem with tapes in the past. Try the FastCap line. One of the guys referred to them above. It took me forever trying to find a tape that didn't have increment lines as fat as a magic marker. I use nothing but fine leaded mechanical pencils in shop so looking for a tape to get me the same accuracy was tough. FactCap's lines are the tightest and most accurate I've found. I bought 2 cases of them at last trade show I attended, I like them so well.
From contributor A:
I have a Stanley tape measure but I try to use it a little as possible. From using the scale on my TS and SCM and using setup blocks for everything from fence dimensions to slide spacing and shelf layout, my tape gets lonely there on my pocket. Doing it that way also helps minimize user error.
From contributor C:
I have found the Stanley Fatmax is bulky and takes some getting used to, but now I'm sold over any tape I have found. Why so many different people measuring to cut in one shop? I thought everyone used a cast iron top and a hammer to get the entire shop reading the same.
From contributor X:
We are a bit different - only use a tape for rough measure. For layout, we have a long scale from the Furniture Institute which we also use to calibrate machines. We rely on the encoders and scales and the computers on the machines and check accuracy regularly. It's a bit different when you are using machines, but it's more important to us to utilize good math and geometry. For us, once I see someone on the bench pull out a tape, I think I've lost it.
