accuracy of stainless rules

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Stray Feathers
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accuracy of stainless rules

Post by Stray Feathers »

I was surprised to discover (during my day job as a picture framer) that in a quick look, there was a discrepancy of as much as 1/32 inch in 24 inches between different stainless measuring scales. One was from a tool store, two were the sort you'd get at a stationery store. I also compared to a couple of tape measures. Having just finished a couple of guitars, I can see that that discrepancy could cause you trouble when laying out necks or fingerboards if you happened to switch rules at some point. It's a reminder that it is good practice to use the same rule for all your work. What I don't know is which of the scales is correct! It would make sense to use one from a luthier supply house, but how do we know they are accurate?
MaineGeezer
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Re: accuracy of stainless rules

Post by MaineGeezer »

If you want a reasonable guarantee of accuracy, get a ruler made by Starrett. A 24" ruler is going to set you back over a hundred bucks though.
http://www.starrett.com/metrology/metro ... tBy=wp/asc
Don't believe everything you know.
Anything is possible if you don't know what you are talking about.
When things are bad, try not to make them any worse, because it is quite likely they are bad enough already. - French Foreign Legion
Danl8
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Re: accuracy of stainless rules

Post by Danl8 »

MaineGeezer wrote:If you want a reasonable guarantee of accuracy, get a ruler made by Starrett. A 24" ruler is going to set you back over a hundred bucks though.
http://www.starrett.com/metrology/metro ... tBy=wp/asc
Agreed: Starrett !
Diane Kauffmds
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Re: accuracy of stainless rules

Post by Diane Kauffmds »

Third agree on starrett.
Diane Kauffmann
Country Roads Guitars
countryroadsguitars@gmail.com
Stray Feathers
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Re: accuracy of stainless rules

Post by Stray Feathers »

Could I borrow your Starrett to check to see which of my scales is accurate?
Diane Kauffmds
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Re: accuracy of stainless rules

Post by Diane Kauffmds »

Stray Feathers wrote:Could I borrow your Starrett to check to see which of my scales is accurate?
I agree to the starrett, because I know the reputation and I'm buying the 6" at the end of the month. Unfortunately, the 24" is still on my "gotta get" list.
Diane Kauffmann
Country Roads Guitars
countryroadsguitars@gmail.com
MaineGeezer
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Joined: Wed Aug 13, 2014 12:14 pm

Re: accuracy of stainless rules

Post by MaineGeezer »

Unlike a lot of companies that chemically etch the graduations, or paint them on, Starrett machine engraves the graduations on their rulers.

More accurate...more work....more cost....
Don't believe everything you know.
Anything is possible if you don't know what you are talking about.
When things are bad, try not to make them any worse, because it is quite likely they are bad enough already. - French Foreign Legion
tippie53
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Re: accuracy of stainless rules

Post by tippie53 »

starret or brown and sharp

there is a difference between a scale and a ruler
you want to buy scales.
John Hall
Blues Creek Guitars Inc
Authorized CF Martin Repair Center
president of Association of Stringed Instrument Artisans
http://www.bluescreekguitars.com
MaineGeezer
Posts: 1711
Joined: Wed Aug 13, 2014 12:14 pm

Re: accuracy of stainless rules

Post by MaineGeezer »

Unfortunately, Brown & Sharpe is no longer a real company. When the company folded some years ago, the brand name "Brown & Sharpe" got sold. If you by a B&S brand something-or-other today, there is no telling who made it, or what quality it is. Tools made by "Brown & Sharpe, Providence, RI," were among the best, but nowadays it's a crapshoot.

Another old-time company that used to make excellent machinist's tools was Lufkin, but they haven't made machinist's tools in years.
Don't believe everything you know.
Anything is possible if you don't know what you are talking about.
When things are bad, try not to make them any worse, because it is quite likely they are bad enough already. - French Foreign Legion
Stray Feathers
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Joined: Sun Sep 08, 2013 11:39 pm
Location: Ladysmith, BC

Re: accuracy of stainless rules

Post by Stray Feathers »

Is anyone familiar with GEI rules which claim to be NIST certified? Quite a bit less than Starrett.
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