Another POV on ww'ing measuring "precision" ...

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I don't necessarily subscribe to the .001" accuracy in woodworking espoused in some of the threads floating around here lately (particularly when a 4" wide board cut this morning at 65 degree/70% rh may well be a different width tomorrow afternoon when it's 95/95), but with wood getting more expensive by the day, it does pay to develop a method/philosophy of measuring, marking, layout and cutting that can get you "consistency" in the dimensioning of your parts ... which is what you should be shooting for when things have to go together as a whole.
On the methodology side, no amount of precision measuring will get you this needed consistency like the "batch" cutting/routing of parts, and the meticulous and consistent "referencing" of faces and edges to fences and cutting surfaces when machining/cutting ... particularly for a "production run" of multiple pieces in a small shop environment.
On the measuring side, I find myself going back repeatedly to the following tools for obtaining this necessary consistency, to the point that I even keep these, and like items, on a large plastic TV tray, lined with a non-skid rubber mat, so I can move them en masse around the shop as I need them:
Incra rule set (with the Bend rule the most used) http://www.incra.biz/Products/RuleSets.html
Veritas Saddle square (one of the most used items in the shop) http://www.leevalley.com/wood/page.aspx?c=1&pD836&cat=1,42936,50298&ap=1
.05mm mechanical pencil (steal this from my shop and you're dead!)
Sliding bevel square http://www.leevalley.com/wood/page.aspx?c=1&p2593&cat=1,42936,50298
Sliding Square http://www.leevalley.com/wood/page.aspx?c=1&p2598&cat=1,42936
Starret combination square
With the above (and paying particular attention to maintaining reference edges), careful layout, marking and subsequent machine setup can be done with enough consistency to carry you from part 1 to part 101 with confidence, regardless of how many zero's of precision you put behind the period.
FWIW/YMMV, etc. ...
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Swingman, I agree with you generally but marking methods and repeatability is always my nemesis. I (almost always) exclusively use my Starrett combination square or sliding bevel along with my 24" rule to make a story pole/stick marked with a sharp knife and notes with actual measurements. This makes repeatability almost stupid-proof.
However for machine setups, I do go back to my machinist attitude and set the machines up with dial indicators, feeler gages, micrometers and dead flat straightedges. My personal tolerances for woodworking machines are +/- 0.002" for most setups. An 8lb single jack persuades any machine that refuses to cooperate!
Dave
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Swingman wrote:

I have a mechanical vernier calliper which is my depth gauge, thickness measuring device and all around do-all to 5". I have a Lee Valley 12" rule... do NOT touch!
Fuck with my mechanical pencils and death will be imminent. My 12" Swanson Speed square(s) a Johnson 48" rule and my 150" 6" x .25" straight edge.. I mean... don't even LOOK at it, okay? I had that one milled by a guy who does propeller shafts for gas-turbine driven high-speed landing craft for the US Marines.... like I said...don't touch! It is over 12 feet of .002"
Other than that, thumbs up to the SwingMeister who seems to do things the way they ought to be done.... not so sure about western Swing music... I went to see my hero John Prine last weekend in London..and I am going to see what is left of The Who this coming weekend.... so whatthefuck do I know, eh?
Prine's song titled Some Humans Ain't Human ripped my heart apart.
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You have to get that man to send you a CD of his band.
It WILL make you a true believer.
As to the measurements - I own every measurement device known to man and have found that "a little bit more" and "a little bit less" are the only truths of wooddorking measurement.
(watson - who owns both a six foot and a four foot Starrett straight edge, a Starrett Dial Indicator, a Starrett Vernier, and would have happily measured in nano-rch's at a certain point in his life - but is happy now to have it, "just about dead close boogie".)
Regards,
Tom Watson
tjwatson1ATcomcastDOTnet (real email)
http://home.comcast.net/~tjwatson1 /
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There is a rather old measurement term that uses a human hair that is not used in mixed company.
I recall carpenters using this term over 50 years ago and it's still used in the construction trades even today.
Tom Watson wrote:

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Pat Barber wrote:

Yup, c-hairs come in red, blonde and black..all slightly different in dimension. But the differences are usually regional and are not a recognized international standard.... especially in Brazil where such measurements are scarce. I wouldn't want to be a cabinetmaker in Brazil... or in certain nordic parts of Russia either...I mean..we're talking rope...
will you look at the time!
r
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"Robatoy" wrote in message

Actually, I've done extensive personal research into this area and can assure you that red is pretty much the same world wide; with blonde, you can only guess unless the lights are on; and with black, like the markings on a tape measure, you must do a side by side comparison.
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wrote:

Isn't that why rch is the only one used for measurement?
http://www.urbandictionary.com/define.php?term=R.C.H .
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George Shouse wrote: > > Isn't that why rch is the only one used for measurement?
Depends on whether you reference the straight or curly version.
Lew
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Uh Oh...now we are "splitting hairs", which is also used as a measurement.
Lew Hodgett wrote:

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Pat Barber wrote:

Current fashion dictates that less of them are around for reference purposes. <G>
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"B A R R Y" wrote in message

Personally, I hate that trend ... I think.
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Swingman wrote:

A little is better than none, and way better than too much. <G>
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"B A R R Y" wrote in message

Obviously, more research is in order.
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Swingman wrote:

Agreed! Yet another area of research revolutionized by the Internet! Or so I've heard... <G>
BTW, I just returned from my local Woodcraft, and they now stock a finishing product called "Bush Oil"!
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<<BTW, I just returned from my local Woodcraft, and they now stock a finishing product called "Bush Oil"!>>
There you go. Persuant to the previous discussion, some people apparently have no use for the stuff. <g>
Lee
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Lee Gordon wrote:

For those, there is a large selection of waxes...
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I agree with the notion that much more research is in order. Being an 'get-to-work' kinda guy. I'll roll up my sleeve and get started.
r
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I once worked with a Swiss optics technician that used the corresponding slang term in either German or Swiss (I don't remember). A bunch of us picked it up over the years. When I started using it around the house, the wife thought it was a real unit of measure. She even started using it. I was getting quite a chuckle until I told her what it meant. I had trouble telling her with a straight face. Man, that was funny. Strange, she didn't think so at the time. :-)
-- d phi / dt
Pat Barber wrote:

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After I reached my current age, I found that some things are best left not said.
Women will hold a grudge for their entire life.
Blue Enamel wrote:

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