Welcome! Please use the navigational links to explore our website.
PartsASAP LogoCompany Logo (800) 853-2651

Shop Now

   Allis Chalmers Case Farmall IH Ford 8N,9N,2N Ford
   Ferguson John Deere Massey Ferguson Minn. Moline Oliver

Attention Forum Users: On the 28th of December 2023 at 9:00am Central Time, we will be taking the forums down for maintenance while we prepare the new forums for your use. Please click here for more information.

Tool Talk Discussion Forum

How do you check out/calibrate a micrometer?

Welcome Guest, Log in or Register
Author 
John in CT

02-13-2006 19:20:37




Report to Moderator

I never owned a micrometer before but borrowed one once in a while that I assumed was pretty accurate. I got a used Brown and Sharp micrometer for my self ( 0"-1"). I want to make sure it is accurate enough to say measure engine components. It looks pretty clean but seems to sometimes bind a little here and there. How do you calibrate/ check it out? Anything else I should check out on it? Do you somehow lube it? I tried it on a certified steel block set(I borrowed) and I get the correct reading (plus and Minus a few .0001"s or less on the verneer. It doesn't have that thimble thing so I am not sure if I tighten it too much or too little. Thanks!!

[Log in to Reply]   [No Email]
Butch(OH)

02-14-2006 07:18:56




Report to Moderator
 Re: How do you check out/calibrate a micrometer? in reply to John in CT, 02-13-2006 19:20:37  
Just measuring a few engine parts? Then forget the rocket science. A mic standard is cheap or in an absolute pinch like you dropped the mic and no standards are handy use shank from a good quality polished finish 1/2 drill bit (.500). To learn how to use it have the mic and whatever you use for a standard in your lap while watching TV. Measure it while not watching the thimble. When you get results within a half thou (.0005) everytime you are as good as you need to be and as good as most are with one. Few mic users can measure to tenths (.0001)with repetable results except in their own mind and even if they can it means little in the world of engine rebuilding or engine parts.

[Log in to Reply]  [No Email]
George Andreasen

02-14-2006 05:23:06




Report to Moderator
 Re: How do you check out/calibrate a micrometer? in reply to John in CT, 02-13-2006 19:20:37  
Thought I'd throw my ten cents worth in here. Any micrometer may be checked using a known reference called a "standard" as mentioned. Both the mike AND the standard should be at a temperature of 68 degrees (Far.) when calibrating is performed. As also mentioned, use a light, consistent touch at all times and close the mike on the standard, noting the reading. If it is slightly off readjust until it reads correctly and lock the adjustment. Check once more.
In truth most mikes keep their adjustment zero for years without problems. Wear, neglect or abuse are their biggest enemies, but I've seen horrible looking mikes that are dead on.
Enco Tools out of Fernley Nevada (shameless plug) has micrometer standards at a very low price. I believe they come in 1" through 6" sizes....just make sure it isn't just tossed in the toolbox. Like the micrometer it is an INSTRUMENT, not just a "tool". Best, George

[Log in to Reply]  [No Email]
Slowpoke

02-14-2006 00:26:16




Report to Moderator
 Re: How do you check out/calibrate a micrometer? in reply to John in CT, 02-13-2006 19:20:37  
It shouldn't be binding unless it's dirty or damaged. I would take it apart and clean the screw threads as well as inside the barrel with a soft cloth and some WD40 or such. Clean to dry and use a little instrument or sewing machine oil on it. Some mikes have a ratcheting thumb screw on the bottom. When measuring, it will always give the same pressure; not too little or too much. Use your standard to set the mike.

[Log in to Reply]  [No Email]
JMS/MN

02-13-2006 22:22:16




Report to Moderator
 Re: How do you check out/calibrate a micrometer? in reply to John in CT, 02-13-2006 19:20:37  
No matter which micrometer you have, you 'zero' it in midrange. You need a standard measure block for that. For example, with a one inch mike- you don't set it at zero when it is closed- you need to split the variance across the entire range of the mike.



[Log in to Reply]  [No Email]
Eric in IL

02-14-2006 07:31:51




Report to Moderator
 Re: How do you check out/calibrate a micrometer? in reply to JMS/MN, 02-13-2006 22:22:16  
Since wear can occur anywhere in the range of a given micrometer, I don't understand the value of checking "zero" only at midrange.



[Log in to Reply]  [No Email]
Jerry L /AZ

02-13-2006 21:40:57




Report to Moderator
 Re: How do you check out/calibrate a micrometer? in reply to John in CT, 02-13-2006 19:20:37  
John, do what coloken says. it should not take any force to get the anvils to close don't force it when you get the feel of the mike and it wont zero, you can calibrate your 0-1" mike by loosening the screw on the end of the barrel if there is a cap on the end you take the cap off to get to the screw. with the anvils togeather there should be two little jam nuts that have a little tiny holes in them you should also have two little wrenches that look like spanner wrenches.loosen those jam nuts with the spanners then you can turn the barrel to zero. tighten the two little jam nuts with the spanners,tighten the screw and opean and close the anvils again check your reading. replace the cap and oil I use a gun oil on my mikes or a lite oil like sewing machine oil on 1-2" 3-4" and up is the same except you use the correct standards. hope this helps Jer

[Log in to Reply]  [No Email]
Coloken

02-13-2006 19:52:57




Report to Moderator
 Re: How do you check out/calibrate a micrometer? in reply to John in CT, 02-13-2006 19:20:37  
Wipe the faces off with a clean cloth, then close it to zero. Check that it says zero, if not you can correct your readings by that amount. While you are doing this, practice the amount of force you use to get zero. This is hard to explain, but you will develope a "touch" that you must use each time you measure. The accuracy depend more on the user than the tool, assuming that it is anywhere near the quality like B&S is.

[Log in to Reply]  [No Email]
Coloken

02-13-2006 19:55:38




Report to Moderator
 Re: How do you check out/calibrate a micrometer? in reply to Coloken, 02-13-2006 19:52:57  
Just read Charles post and remembered that all micks dont go to zero, so use the gage block like he says.



[Log in to Reply]  [No Email]
Charles (in GA)

02-13-2006 19:48:50




Report to Moderator
 Re: How do you check out/calibrate a micrometer? in reply to John in CT, 02-13-2006 19:20:37  
Some micrometers come with a "standard" which is used to check the mic. These standards are precision made and are traceable to the US bureau of standards. This is the easiest, best way to chekc the mic.

I have a very old B&S, 1 to 2 inch with a round one inch standard in the box.

Many of the Mitutoyo mics come with standards, as listed in the Grainger catalog.

Go to www.mscdirect.comm and do a keyword search for "micrometer standard" (without the quotes) and you will get a listing of about 8 screenfulls of standards, from one inch up.

Charles

[Log in to Reply]  [No Email]
[Options]  [Printer Friendly]  [Posting Help]  [Return to Forum]   [Log in to Reply]

Hop to:


TRACTOR PARTS TRACTOR MANUALS
We sell tractor parts!  We have the parts you need to repair your tractor - the right parts. Our low prices and years of research make us your best choice when you need parts. Shop Online Today. [ About Us ]

Home  |  Forums


Copyright © 1997-2023 Yesterday's Tractor Co.

All Rights Reserved. Reproduction of any part of this website, including design and content, without written permission is strictly prohibited. Trade Marks and Trade Names contained and used in this Website are those of others, and are used in this Website in a descriptive sense to refer to the products of others. Use of this Web site constitutes acceptance of our User Agreement and Privacy Policy

TRADEMARK DISCLAIMER: Tradenames and Trademarks referred to within Yesterday's Tractor Co. products and within the Yesterday's Tractor Co. websites are the property of their respective trademark holders. None of these trademark holders are affiliated with Yesterday's Tractor Co., our products, or our website nor are we sponsored by them. John Deere and its logos are the registered trademarks of the John Deere Corporation. Agco, Agco Allis, White, Massey Ferguson and their logos are the registered trademarks of AGCO Corporation. Case, Case-IH, Farmall, International Harvester, New Holland and their logos are registered trademarks of CNH Global N.V.

Yesterday's Tractors - Antique Tractor Headquarters

Website Accessibility Policy