dial calipers for woodworking "link"

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Yes, but you could get yourself a 12" Vernier caliper graduated in .001" increments (1/64 is approximately .032") for about the same price, and you don't need to worry about sawdust working it's way into any mechanical parts. Also, I saw someone else suggest a digital caliper, and in my experience, they are junk unless you want to pay for a Miyoto, Brown & Sharpe or something of equal quality. If you get one of those "import" ones, they have a tendancy to give wild readings after a relatively short period of time. The vernier takes a little getting used to compared to a simple dial caliper, but it's worth the minimal effort involved to get a tool that will last forever, rather than one that will likely fall apart after a year or two- especially if you drop it or get it wet at all.
All differences in caliper types aside, they are truly excellent tools for a lot of different applications, especially for measuring depths in holes or mortices that are too small to allow you to slide a rule into them.
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On Fri, 24 Sep 2004 19:14:18 -0500, Prometheus

.015625
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heh...heh...heh...cool. A.
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Got one! Actually a really nice one made by Catic in HKC, of hardened stanless. It is a proper design compared to the common General(T) brand (has the oval cut-out window) and is layed out like this one, see the graphic here: http://www.rit.edu/~uphysics/VernierCaliper/caliper.html I just cannot "pick-up" on how to read it even from the lesson on this page. It's inch increments are 1/40" at the smallest, someone told me that is 0.025". I just don't get it with the decimals thing, but then again I was recently diagnosed with ADHD, I'm a now a no brainer lol.
Thanks for the encouragement though, I would LOVE to find an easy way to learn it.
Alex
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Alex- I'll give it a shot. first, grab a normal old tape measure or a ruler or something, just for a sanity check. use it to check the marks on the beam of the caliper. note that the inches are the proper distance apart. then notice that the inches are divided up into 10ths instead of 16ths like on a typical woodworker's tapemeasure. then notice that each of those tenths is divided into 4 parts. so at this point we can read the "full scale" units directly off of the beam to a resolution of .025... which is to say one quarter of one tenth of one inch. but the tool is meant to be read to a resolution of one thousanth of an inch, or .001. so note that one thousanth is one twentyfifth of the smallest marks that we can read directly off of the scale on the beam. so what we have to do is divide those smallest marks on the beam into 25 smaller parts, which would be way too close together to read without strong magnification. so what we do is read the thousandths off of the OTHER set of marks, the ones on the moveable jaw. note that there are in fact twenty five marks there. so first slide the jaw closed. here we know that we are measuring a distance of zero inches. note that the zero and the 25 marks on the vernier scale (the ones on the moveable jaw) line up with SOMETHING on the beam. note that the other marks on the vernier DON'T line up, though the ones at the ends come close. so now let's pretend that we have something that is 7/8ths of an inch thick that we want to measure. 7/8" is the same as 0.875. so the 0 mark (our starting point) on the vernier is gonna between the 8 tenths mark on the beam and the 9 tenths mark. there are 3 marks between, dividing that tenth into 4 parts, which in this case are .825, .850 and .875. and the zero on the vernier will land right on the third of them, the .875. so in this case we didn't need the vernier scale other than to check ourselves. so now let's set the caliper for say one and seven sixteenths inches (1.4375). actually, we will have to settle for getting within a thousandth of that, because this tool can't do the last decimal point. the one inch part is easy- the zero on the vernier (on the moveable jaw) is somewhere between the 1 inch mark and the 2 inch mark. so 1.4375 is somewhere between 1.4 and 1.5 on the tenths marks, so slide the jaw over into that range. between 1.4 and 1.5 there are 3 marks, representing 1.425, 1.450 and 1.475. What we want, 1.4375 is going to be somewhere in between the 1.425 and 1.450 marks. get the zero on the vernier (on the moveable jaw) in between those marks. now shift your eye over to read the vernier scale. here we have to decide how we want to round off the forth decimal point. this caliper can read either 1.437 or 1.438 but not 1.4375. just for kicks I'm gonna use 1.438. so what I do is count up from 1.425 (where the zero is on the beam) to 1.438 on the vernier scale, which gets me to the 13 mark on the vernier. (1.4)...25 + 13 (1.4)....38. so line up the 13 mark on the closest mark on the beam. here's where it gets confusing, because the beam scale mark that the vernier 13 is lining up with is not the mark we are reading. we are reading the location of the zero on the vernier (on the moveable jaw) for the rough measurement (within 25 thousandths) and the vernier scale for the fine measurements (within 1 thousandth), ADDING THE VERNIER READING TO THE BEAM READING.
aack. that was terrible. a lotta buncha words to get a simple concept across, and I'm not sure I even got there. the first few times it will be a challenge. I'd recommend getting a set of feeler guages and practise measuring those- they'r very accurate, cheap and have the decimal thickness etched right on them. after a while it gets to be second nature to pick the numbers right up. the vernier caliper is a great tool- very simple, very reliable, no batteries or digital displays to go bad, no gears and dials to wear out- just takes a little cypherin'
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Okay, that was confusing to me, I admit it. It did add to my "mental cohesion" in thinking form though. I did go through it carefully but I do have mental blocks to fight through.
I did another search and found this cool page if you'll take a peek at it: http://www.uiitraining.com/b51a/100/13102vernier_caliper%2Cetc.htm It seems like something cleared up, as I studied, I did the following: (finger knuckle width on skin touch, not squeezed)
V-0 index is between 0.68 and and 0.80 beam, match is 7th V-line to the 6th 0.25 beam = 0.75? 0.68" beam + 0.07 Vscale = 0.75"
Is that correct?
Alex
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I don't *think* so... ya got me confused... I think....
OK. so the marks on the vernier are thousandths- that is the third decimal place (.001) rather than hundredths, which is what it looks like you're calling them above. so if the beam reading is .68 and the vernier reading is 7 you'd get .687.
train yourself to ignore which line on the beam it is that the line on the vernier lines up with (other than the vernier 0, of course).
at 0.75, the V0 will exactly line up with the beam 0.75.
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As a former Calibration Technician, I used to work on the vernier and micrometer bench. I found that the Mitutoyo equipment I worked on withstood the test of time. Most of the equipment was from a Navy base where it got practically constant use, and it <the equipment> frequently came in well within manufacturer specs. Some equipment mostly in the digital side would stay good even up to the 1/10000 inch, but would require frequent battery changes <6-9 months>. All these mics and verniers will eventually need adjustment, but some will stay in alignment for up to a decade depending on use.
Some of the other companies's calipers just could not stand up to the workload and would be back every 13 weeks for re-calibration.
Note, I do not even have any mics or verniers, and my advice is just that, advice. Not legally binding, and your mileage may vary.
On Fri, 24 Sep 2004 19:14:18 -0500, Prometheus

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That's very good, thanks for the perspective. Alex
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