# Six inch machinist rules



## GailInNM (Dec 26, 2008)

I use the semi-rigid standard 6 inch machinist rules a LOT. So I have a bunch of them. There are probably a dozen around the shop. Seems that I buy one or two when ever they are on sale. 

One use is as a feeler gage to set up tool clearances, but as the rules I have are from assorted manufacturers they vary some what in thickness from 20 to 26 thousands thick. As I never know what rule is going to be where, I measure and engrave all of them with the thickness. I use one of the standard vibrating engravers as made by Dremel and others. Then I don't have to measure them each time.

To keep them near by each machine tool, I stick a small super magnet to the machine tool so the rule is in easy reach. Then, as I throw it, I just have to point the rule in the general direction of the magnet and it is stored. I positioned the magnets so the rule would hang down over and edge a little bit so it was easy to get hold of. I found the magnets would slide a little bit when I pulled a rule from it, so after each magnet had been in place for a few weeks and I was sure of where I wanted, I put a drop of super glue under it to keep it in place.

I now have rules on my two lathes, two mills, band/cutoff saw, sheet metal shear, and tool grinder. I have several places that I store raw materials, common names "junk boxes", and there is a rule near each of them also. And then there are a couple more on the workbench bench just for utility. 

Gail in NM,USA


----------



## Maryak (Dec 26, 2008)

Great idea Gail,

I have 2 sets of rules of 6" and 12" One set I use with the machines and the other set I keep for marking out. The idea behind this is that those used with the machines take a bit of a beating and wear on the ends, (well perhaps that's my abusing them), and so for marking out their accuracy is compromised.

Best Regards
Bob


----------



## Tin Falcon (Dec 26, 2008)

I was taught in tech school to use a 6" rule to set tool height on a lathe. You gently pinch the rule between the tool and the round work . if the rule is vertical the height is correct. If the tool is high the top of the rule will be pushed in if the tool is low it will push the bottom. 
tin


----------



## Cedge (Dec 26, 2008)

I picked up a half dozen of the 6 inch rules, on sale, recently. They are on every machine and within easy reach around the shop. They get used fro all sorts of things besides those funny little marks they came covered in....(grin)

Steve


----------



## GailInNM (Dec 26, 2008)

I just walked back from the lathe after using one of the rules to back a strip of 2000 grit abrasive paper that I used to polish and take off an unmeasurable (by me anyway) amount of material on a piston that was just a little wiggle too tight. Probably removed less than 10/1000000 of an inch of material. 
Gail in NM,USA


----------



## rake60 (Dec 26, 2008)

My 6 inch scales are probably the most abused tools I own.
These examples have many years of experience.





The lower is a rigid scale. That turned up corner on the 1/8's side is a
battle scar. I can't remember just how I managed to do that.
Maybe that's a good thing....

Rick


----------



## Cliff (Dec 27, 2008)

Hey Ric 
 I have heard that if you take a rule like that and stick it in next to the cutter on a old horizontal mill that is older that old and try to measure the length of your cut or clean some chip's the cutter will put a mark in it like that and through it back at you "so I have heard". 

  Cliff

 P.S. BTW It will scare the heck out of you "so I have heard"


----------



## compound driver 2 (Dec 27, 2008)

RDG tools in the Uk send a free one out with orders over £50. I have about 11 of them now. Most I give away but some i keep in the tool boxes. Six inch rules are perfect for machine work.


----------



## Julian (Jan 1, 2009)

I get several of these at every eng fair. Probably have twenty plus. I have nails on the walls near every machine and in between wherever I have found a need to place one. When I need one I only have to turn round and pick it up and there it.......................ISN'T!!!!!!!!!!!!!!!!!!!!! After several days they are all sitting on the same bench at the square of the longest distance I can reach multiplied by the day of the week. Magnets are great as they pass on a little magnetism after a while so they are all still out of my reach but very nicely stuck together!!!!!!!!!!!!!!!!!!!!!!!!!!


Julian.


----------



## tmuir (Jan 1, 2009)

compound driver 2  said:
			
		

> RDG tools in the Uk send a free one out with orders over £50. I have about 11 of them now. Most I give away but some i keep in the tool boxes. Six inch rules are perfect for machine work.



I've got one of those by my PC and one on my workbench and the third one I gave to my mother in law. :big:


----------



## Mike N (Jan 1, 2009)

Did you know if you take a 6" scale & brake it off at even 1" lines the pieces are within .002" of an inch. 

6" scales make good box openers, butter knives, paint scrapers, epoxy stir sticks, label peelers, Orange & apple peelers, putty knives, sandpaper backers, dental floss, etc.

I wonder what all of those little lines & numbers are for? ??? 
Why can't I ever find one when I need one? ???


----------



## John S (Jan 1, 2009)

There is no perfect 6" rule because everyone's needs are different.
Some only work in inches, some in millimetres and some need both,.

Some are single sided and some double.
The combined ones often have mm on the top row and inches on the bottom, sometimes you need the mm to be on the bottom to get into a corner, sometimes on the top.

So if you have one with inches on one side and mm on the other this should satisfy every one ?

NO.

Because then you have inches say on the top in fractions and inches on the bottom in decimal [ who measures in decimal inches with a rule ? and who uses 1/20" ? ] On the mm side you have the first 50 odd mm in 1/2 mm just to add clutter, lest face it if you can't divide a mm by eyesight then you ought to take up dressmaking.

So is it possible to get a perfect rule ?






 :big:

Not unless you make your own.

JS


----------



## Stan (Jan 1, 2009)

Those silly rules (and tape measures) with metric on one edge and inch on the other edge drive you nuts. If you measure from the left you read in metric, turn it around to measure from the right and you read inches, unless you walk around behind the lathe to read the metric right side up. ;D


----------



## Davyboy (Jan 1, 2009)

Mike N  said:
			
		

> Did you know if you take a 6" scale & brake it off at even 1" lines the pieces are within .002" of an inch.



Yes, I have several 1, 2, 3 4 & 5" scales in my tool box, as well as full size ones. The shorter ones come in handy in confined spaces. I use the holder that came with a radius gage set to hold the small scales where my fat fingers don't fit. Sorry no pics, it's all locked up at work til next week.

DB


----------



## Kermit (Jan 2, 2009)

John Stevenson  said:
			
		

>



You'd end up with some strange dimensions using 26.4 mm because everything I've every transposed into metric from inch used 25.4 mm to the inch!

 You don't suppose that all my books are wrong, are they? After all, it is written in steel.  


Kermit


----------



## John S (Jan 2, 2009)

Must be true, it's written in steel and now been on the internet 

Had a few pic's of rules but this is the only one I can find, had another that was also printed wrong it went 7", 8", 9", 11", 10", 12"

Also American, made by PEC the same as this one. You would have thought that after all these years of fighting off metric and staying imperial they would have go it it right ? :big:

JS.


----------



## Phelonius (Jan 25, 2009)

I am always needing six inch rules. Mine tend to evaporate just before I need them.

 Phelonius


----------



## Shadow (Jan 25, 2009)

I cut a spare one just beyond 3" (round the end to look official and helps prevent snagging) and put it in my billfold. Comes in handy at the hardware store when you find something about the right size but want to make sure.


----------



## TinkerJohn (Jan 25, 2009)

Shadow  said:
			
		

> I cut a spare one just beyond 3" (round the end to look official and helps prevent snagging) and put it in my billfold. Comes in handy at the hardware store when you find something about the right size but want to make sure.



Now, that's a great idea....That's my project for tomorrow night!

---TinkerJohn---


----------



## GailInNM (Jan 25, 2009)

> I am always needing six inch rules. Mine tend to evaporate just before I need them.



I find that if you buy enough of them they start to condense out of the air in the most unusual places.
Gail in NM,USA


----------



## Maryak (Jan 25, 2009)

Kermit  said:
			
		

> You don't suppose that all my books are wrong, are they? After all, it is written in steel.



Nope - that only applies if it's SET IN CONCRETE 
	

	
	
		
		

		
			





Best Regards
Bob


----------



## Kludge (Jan 26, 2009)

Okay, now that I've figured out we're not talking about rules for machinists who are all of 6" tall or only use 6" lathes (I did mention being a bit slow, right?) ... 

The ones with the pocket clips are cool for quick 'n dirty depth gauges too. They don't have the accuracy real ones do but they're good for "in the neighborhood" measurements. And if one uses pocket protectors they are good for bonus points in geekitude.

BEst regards,

Kludge


----------



## tel (Jan 26, 2009)

Shadow  said:
			
		

> I cut a spare one just beyond 3" (round the end to look official and helps prevent snagging) and put it in my billfold. Comes in handy at the hardware store when you find something about the right size but want to make sure.



I had about 2" of one left over when I chopped one up for the scales on my ball turner tool heads - that bit lives on my key ring


----------



## mklotz (Jan 26, 2009)

A one inch chunk fitted with a handle about six inches long makes a good tool for making measurements inside cavities, etc. where a conventional scale or calipers will not fit. Fit the handle with a clamp affair to hold the scale chunk and you can angle the scale or use other widths salvaged from the donor scale.


----------



## Mainer (Jan 26, 2009)

Like Starrett #423? http://catalog.starrett.com/catalog/catalog/groups.asp?GroupID=168
I've got a set -- I don't use it much, but sometimes it's just the thing.


----------



## mklotz (Jan 26, 2009)

Yes, exactly. In fact, that's where I got the idea. As you say, seldom used but just the ticket for certain jobs.


----------



## Noitoen (Jan 26, 2009)

Kludge  said:
			
		

> Okay, now that I've figured out we're not talking about rules for machinists who are all of 6" tall or only use 6" lathes (I did mention being a bit slow, right?) ...



And I thought that Portuguese was a tricky language. For me the title of this thread was about rules or regulations for little six inch machines (wondered if they were lathes or mills). I thought that those little measuring "thingies" were called *rulers*, but, again, I'm Portuguese and here we normally have "réguas de 30 centimetros" ;D

Helder


----------



## ksouers (Jan 26, 2009)

I was taught to refer to them as scales, since they are a "precision" measuring tool as opposed to a ruler which is not precise. Precision in this context refers to repeatability and conformity. Scales are calibrated to a standard. Take 10 different tape measures or rulers and you will have 10 different definitions of an inch. Take 10 different precision scales and they should all measure an inch the same.

It's a habit that stuck. Rulers are rulers but a machinists rule is a scale.

Though it's obvious there can be errors in manufacture.

Kevin


----------



## mklotz (Jan 26, 2009)

Like you, Kevin, I had it beaten into my head that that thing I use to stir my coffee is a scale, and not a rule or ruler.

Times must have changed, however, since even Starrett now refers to them as rules (not rulers)...

http://catalog.starrett.com/catalog/catalog/PLH2.asp?NodeNum=21812&Mode=PLIST

I'll continue to call it a scale. If nothing else, it sounds more elegant and this world is sadly lacking in elegance.


----------



## Noitoen (Jan 27, 2009)

mklotz  said:
			
		

> Like you, Kevin, I had it beaten into my head that that thing I use to stir my coffee is a scale, and not a rule or ruler.



You can't use a scale to stir you coffee, because it will expand with the heat and the loss of precision will turn it into a rule or ruler. :big: :big:


----------



## Stan (Jan 27, 2009)

I'm not sure about the precision thing. Back when I used to do layouts for printed circuit boards, I had a series of boards with unexplained errors. I eventually found that one of the inches on my 'precision scale' had eleven tenths. Being machine made, I expect there are thousands of those still in circulation.


----------



## kvom (Jan 27, 2009)

> If nothing else, it sounds more elegant and this world is sadly lacking in elegance.


I'm sorry, but someone who uses that Einstein photo as an avatar can't complain about elegance.  ;D


----------



## BobWarfield (Jan 27, 2009)

Every board I visit, the 6" scale is worshipped as the essential tool to have at hand.

I just have yet to find I needed one. I use digital calipers, height gage, tape measure, and micrometer (in that order of frequency) to do just about everything mentioned here. The lathe tool height setting gets done with a funny little bubble level widget I got somewhere. If I hadn't bought that, then I would need a 6" scale!

In retrospect, that would've been better, and I wouldn't feel so left out and unprofessional.

Cheers,

BW


----------



## rake60 (Jan 27, 2009)

Bob
Can a digital calipers, height gauge, tape measure or micrometer sweep away the gathering
stringer chips on a rotating part and still be useful after doing that? 

The 6" scale is probably the most abused tool ANY machinist will ever own but it will
still be functional after all of that abuse.

Rick


----------



## ksouers (Jan 27, 2009)

I've had my oldest 6 inch scale for 30 years now, haven't had to change the batteries yet ;D


----------



## moconnor (Jan 28, 2009)

Hello All:

*With regards to the PEC rules with the mis-prints...*

I worked as an instructor at our local vo-tech and when the enrollment and budget dropped, the school would look for cost savings where it could. One of the instructors was very good at finding deals and he found that PEC 'seconds' were available somewhere. I don't remember where. Most often I found that the rules were considered seconds for a minor cosmetic flaw that would not effect the function. It is quite possible that the tools John S has seen have been some of these seconds. If I were a manufacturer of precision measuring tools, I wouldn't want my factory seconds (scrap) out in circulation. oh:

Regards,
Mike


----------



## BobWarfield (Jan 28, 2009)

rake60  said:
			
		

> Bob
> Can a digital calipers, height gauge, tape measure or micrometer sweep away the gathering
> stringer chips on a rotating part and still be useful after doing that?
> 
> ...



Nah, I use chip brushes for that. I stuck a magnet on the handle of a bunch of 'em and so there are a couple hanging on each machine.

Good thought though! I'd hate to try to stick the height gage in there for that purpose, LOL.  

Best,

BW


----------



## shred (Jan 28, 2009)

Bob, you're not alone. I too rarely use a 6" rule for anything other than stashing in the car for occasional impromptu measuring at the hardware store or scrapyard.
Every so often I might center a lathe tool with one.


----------

