Dial Bore Gauge or Mics and Telescoping? - Hot Rod Forum : Hotrodders Bulletin Board
Hotrodders.com -- Hot Rod Forum



Register FAQ Search Today's Posts Unanswered Posts Auto Escrow Insurance Auto Loans
Hot Rod Forum : Hotrodders Bulletin Board > Tech Help> Garage - Tools
User Name
Password
lost password?   |   register now

Reply
 
LinkBack Thread Tools
  #1 (permalink)  
Old 07-14-2009, 08:09 PM
Registered User
 
Last photo:
Join Date: Apr 2009
Location: Santa Cruz
Posts: 38
Wiki Edits: 0

Thanks: 0
Thanked 0 Times in 0 Posts
Dial Bore Gauge or Mics and Telescoping?

So here's the deal. I've got a set budget for measuring tools. The first and most important tool I'm wondering about is the outside mic. How suitable is the adage, "you get what you pay for." If I just want to find taper, skirt collapse, out of round and such, will no-name brands make the cut? I like the 0-4 mic set from powerhouse.

http://www.compperformancegroupstore...de=MICROMETERS

They're obviously not much compared to Mitutoyo or Starret, but will these suffice? Will they last and detect engine conditions mentioned earlier? Also, I need your suggestions concerning cylinder, main bearing bore, and bearing crush measurements using a dial bore gauge or mics and telescoping.
I understand Telescoping gauges take practice to get consistent readings. With practice however, will they reach accuracy acceptable against a dial bore gauge? See, the dial bore gauges I'm considering range 2-6 inches while telescoping gauges begin at 5/16". Doesn't that justify the telescoping purchase over a telescoping gauge? Maybe I'm missing something. Please answer my questions. Thank you for your time assissting a newbie. I appreciate it.

    Advertisement
Reply With Quote Quick reply to this message
Sponsored Links
Advertisement
 
  #2 (permalink)  
Old 07-14-2009, 09:01 PM
Member
 
Last photo:
Join Date: Jan 2003
Location: tennessee
Posts: 5,912
Wiki Edits: 0

Thanks: 0
Thanked 7 Times in 7 Posts
Looking at the prices there I would suggest Enco instead, those import Mics are all about the same but very wildly in pricing. As far as that Mic set I think you can beat that, Enco has a 0-6" import set for only $17 more and a set of Fowlers in 0-4" set is only $155 at Enco. Also I would not recommend those telescoping gauges at all since an expensive set is hard enough to do an accurate job with and the cheapies are even worse, it takes quite a bit of practice to be really accurate with them and with practice an inside caliper will work just as well. I use one of these except mine is the "Extender" version that will measure from 1.4" to 6",

www.use-enco.com/CGI/INSRIT?PMAKA=SP890-9842


They are easy to use and accurate, these are Fowler and cheaper ones are out there but at $80 (on sale but then they almost always are) these are a bargain.



www.use-enco.com

Last edited by oldred; 07-14-2009 at 09:09 PM.
Reply With Quote Quick reply to this message
  #3 (permalink)  
Old 07-15-2009, 06:06 AM
Registered User
 
Join Date: Jul 2009
Location: houma, la
Posts: 11
Wiki Edits: 0

Thanks: 0
Thanked 0 Times in 0 Posts
First let me say I work with these gages everyday. I would not use a T-Mic to check those diameters that you referenced. I know these gages are pricey but, how pricey is a motor? Check on E-Pay. One of our machinist's purchased a Fowler Tri-Mic set (3/4"-4-1/2"?) for under a 1000.00. I'm sure there are those that have bought the cheap stuff and have had no problems.
Then there are also the horror stories of those that had problems.
Reply With Quote Quick reply to this message
  #4 (permalink)  
Old 07-15-2009, 07:37 AM
Member
 

Last journal entry: JB's 37 Pickup
Last photo:
Join Date: Oct 2002
Location: Smoky Mountains
Age: 76
Posts: 2,358
Wiki Edits: 0

Thanks: 0
Thanked 2 Times in 2 Posts
Shop around if you have the time. My Bud and I bought out a retired tool and die dealer's hobby machine shop that he had in his basement. In this purchase, there was almost every precision measuring tool ever thought of and most were Starret. We took many of them to old car swap meets and practically gave them away at $10, 15, 20, and 25 each. All were used but in excellent condition. My Bud is a retired master tool and die guy and he has the knowledge and skill to use these tools and I have learned a lot from him. While inside guages do take a bit of practice, it is not rocket science and if you can do basic street rodder skills, you can master them.

Trees
Reply With Quote Quick reply to this message
  #5 (permalink)  
Old 07-15-2009, 09:14 AM
Member
 
Last photo:
Join Date: Jan 2003
Location: tennessee
Posts: 5,912
Wiki Edits: 0

Thanks: 0
Thanked 7 Times in 7 Posts
Quote:
Originally Posted by trees
While inside guages do take a bit of practice, it is not rocket science and if you can do basic street rodder skills, you can master them.Trees


I have a set of Brown&Sharps telescoping gauges that cost over a hundred dollars and even before I bought my dial bore gauge I never used them. I just never found anything that they were good for that I could not do just as easily as I could with a $10 inside caliper and, for me anyway, the caliper was much easier to get an accurate reading but both methods take a lot of practice to develop the right "feel" to get anywhere near the accuracy of the bore gauge. The dial bore gauge is very accurate, far easier to use, is self-centering and generally takes any guess work out of the procedure.
Reply With Quote Quick reply to this message
  #6 (permalink)  
Old 07-15-2009, 10:05 AM
Frisco's Avatar
Glad To Be Here
 
Last photo:
Join Date: Nov 2002
Location: Canton, North Carolina
Age: 72
Posts: 2,244
Wiki Edits: 0

Thanks: 0
Thanked 8 Times in 8 Posts
A dial bore gauge or tri-mikes (also referred to as intra-mikes) are the most accurate when used correctly and also the most expensive.

Inside mikes are the next for accuracy and less costly. I still would use a set of O.D. mikes over the inside mikes for comparative readings.

Telescope gauges (must be used in conjunction with O.D. mikes) are also easy to use and very accurate and are the cheapest.

Inside calipers (whether dial or not) are very easy to use and also the least accurate. Most (even the BEST brands) are only guaranteed to be + or - .010 in accuracy.

As with all precision measuring instruments, developing the proper "feel" is key to achieving accurate results. This is truly a case where "practice makes perfect"

For what you are doing, a set of telescope gauges and good quality outside mikes will work best and be the most cost effective.

If you were going into business doing machine work, then better quality and more costly instruments would be warranted as well as an ongoing calibration program.
Reply With Quote Quick reply to this message
  #7 (permalink)  
Old 07-15-2009, 11:04 AM
bentwings's Avatar
bentwings
 
Last photo:
Join Date: May 2002
Location: St.Paul, Minn
Age: 72
Posts: 1,796
Wiki Edits: 0

Thanks: 0
Thanked 16 Times in 15 Posts
The bore gage set that oldred shows is fine and the 0-6" mic set will be needed to to set the bore gages easily. They will last a lifetime if taken care of. They are presision tools so treat them gently and cleean and return them to their storage boxes when done. Seems like a lot of $$$ but I have found that a project will stall if you don't have the right tools at hand. It is a real pain to have to run around town to get help from people that seem to never be around when you need help.
Reply With Quote Quick reply to this message
  #8 (permalink)  
Old 07-15-2009, 11:12 AM
Member
 
Last wiki edit: Ford axle ratio codes
Last journal entry: Rear Suspension
Last photo:
Join Date: Aug 2005
Location: Prattsville
Posts: 6,363
Wiki Edits: 31

Thanks: 2
Thanked 55 Times in 51 Posts
a set of inside mic's and a set of outside mics will be all that's nessasary for a standard rebuild... I'v always referred to the inside mic's as " snap gauges "
Reply With Quote Quick reply to this message
  #9 (permalink)  
Old 07-15-2009, 12:38 PM
Member
 
Last photo:
Join Date: Jan 2003
Location: tennessee
Posts: 5,912
Wiki Edits: 0

Thanks: 0
Thanked 7 Times in 7 Posts
Quote:
Originally Posted by Frisco
Inside calipers (whether dial or not) are very easy to use and also the least accurate. Most (even the BEST brands) are only guaranteed to be + or - .010 in accuracy.


http://www.use-enco.com/CGI/INSRIT?P...PARTPG=INLMK32


These calipers are just as accurate as the person using them which is also true of the telescoping gauges, both require a developed "feel" for the proper amount of tension and feel for the center, they actually work on the same principle. The accuracy depends entirely on the skill of the user to properly center and level the tool in the bore and to be able to "feel" the right amount of drag when passing the lowest point, a new user of either of these instruments can usually take a dozen different readings and get a dozen different results and even a pro should go back and verify his reading to make certain. In the hands of a pro either of these tools will work just fine but the dial bore gauge makes it very easy to not only check (accurately check) bore diameter but to quickly determine bore taper and exact location of high and low points in out-of-round bores which can be time consuming with calipers or telescoping gauges. As far as the calipers being only accurate to within +/- .010 they can be used for far more accurate results than that and I have for years used them to bore for bearing and bushing fits.
Reply With Quote Quick reply to this message
  #10 (permalink)  
Old 07-15-2009, 06:52 PM
Registered User
 
Last photo:
Join Date: Apr 2009
Location: Santa Cruz
Posts: 38
Wiki Edits: 0

Thanks: 0
Thanked 0 Times in 0 Posts
Oldreds got me convinced as far as enco bore gauge and outside mikes. However, everyone else keeps mentioning the inside caliper. If I have a dial bore gauge range at 2-6", will I meet important bores not within this range? If so, is the inside caliper worth the purchase?

Thanks everyone for the help. You responded quickly and thoroughly. A+ for you.
Reply With Quote Quick reply to this message
  #11 (permalink)  
Old 07-15-2009, 07:53 PM
Member
 
Last photo:
Join Date: Jan 2003
Location: tennessee
Posts: 5,912
Wiki Edits: 0

Thanks: 0
Thanked 7 Times in 7 Posts
Those inside calipers like the one I linked to are so cheap that cost is not much of an issue and besides they are handy for a lot of things. Once you develop a feel for using them (getting really accurate with them is an art) they can be used for almost any inside measurement and make a good addition to the bore gauge, a set of outside calipers is a good idea too. For less than $20 more you can get the "Extender" version of that Fowler bore gauge that will extend the range down to less than 1 1/2" if you have a need for it, for engine work the standard set with the 2" limit should suffice however. That Fowler set is the one I have and it is a well made precision tool that is very accurate and reliable plus it is easy to use, they are a really neat trick for engine cylinder bores and I simply would not be without one!
Reply With Quote Quick reply to this message
  #12 (permalink)  
Old 07-15-2009, 08:11 PM
Member
 
Last photo:
Join Date: May 2004
Location: N.C.
Age: 75
Posts: 241
Wiki Edits: 0

Thanks: 0
Thanked 1 Time in 1 Post
Quote:
Originally Posted by LittlePwny
Oldreds got me convinced as far as enco bore gauge and outside mikes. However, everyone else keeps mentioning the inside caliper. If I have a dial bore gauge range at 2-6", will I meet important bores not within this range? If so, is the inside caliper worth the purchase?

Thanks everyone for the help. You responded quickly and thoroughly. A+ for you.
You got good advise on the hole. A dial bore gage is THE ONLY way to go if you need a accurate measurement in a hole outside mikes for the outside. Oh you did't say if you knew how to read the things? if not go to your local trade school and get a crash course or at lest get a buddy that can show you and remember its all in the feel on the mikes! they an't c-clamps and WILL not read right if you use them that way plus will have to be reset if used this way. best of luck just remember all it takes is a little practice and you can be as accurate as us 25 year machinist.

OLDROD
Reply With Quote Quick reply to this message
  #13 (permalink)  
Old 07-16-2009, 01:06 AM
Registered User
 
Join Date: Sep 2005
Location: Two Rivers Wi.
Age: 72
Posts: 451
Wiki Edits: 0

Thanks: 0
Thanked 0 Times in 0 Posts
The main difference in the good machinist tools and the run of the mill is how they are made.

For somebody new at this to really see the difference in the two, you will need lets say two 0-1'' micrometers.

Maybe a starret, and a less pricey brand, but not real cheap one.

Now unscrew it all the way out and take a magnifying glass and look at the threads, you will see the starret brand has nice smooth threads, and the other brand will have some rough looking threads, a real eye opener once you see them together.

What happens here, when you turn down on something to measure it, it will feel spongy, you won't get the definite yeah thats it stop, even with your finger tips.

Rob

http://www.1969supersport.com

Last edited by robs ss; 07-16-2009 at 01:21 AM.
Reply With Quote Quick reply to this message
  #14 (permalink)  
Old 07-16-2009, 08:35 AM
Frisco's Avatar
Glad To Be Here
 
Last photo:
Join Date: Nov 2002
Location: Canton, North Carolina
Age: 72
Posts: 2,244
Wiki Edits: 0

Thanks: 0
Thanked 8 Times in 8 Posts
Quote:
Originally Posted by oldred
http://www.use-enco.com/CGI/INSRIT?P...PARTPG=INLMK32


These calipers are just as accurate as the person using them which is also true of the telescoping gauges, both require a developed "feel" for the proper amount of tension and feel for the center, they actually work on the same principle. The accuracy depends entirely on the skill of the user to properly center and level the tool in the bore and to be able to "feel" the right amount of drag when passing the lowest point, a new user of either of these instruments can usually take a dozen different readings and get a dozen different results and even a pro should go back and verify his reading to make certain. In the hands of a pro either of these tools will work just fine but the dial bore gauge makes it very easy to not only check (accurately check) bore diameter but to quickly determine bore taper and exact location of high and low points in out-of-round bores which can be time consuming with calipers or telescoping gauges.
I agree with the above statement.

The link you provided is to a set of dividers not calipers. Dividers are the least accurate method of measuring with. They are often used for non-precision measuring by machinist & toolmakers; but more often by woodworkers and carpenters.

I am a retired Master Tool & Die Maker after 42 years. If I was going to have machine work done by someone else and I saw them using dividers to measure with; I'd be looking for another machine shop.

Quote:
Originally Posted by oldred
As far as the calipers being only accurate to within +/- .010 they can be used for far more accurate results than that and I have for years used them to bore for bearing and bushing fits.
I do not dispute that vernier calipers can be used to quickly and quite easily get a measurement and can also be accurate. What I posted is what the manufacturers will guarantee as to the accuracy.

Many brands of vernier calipers (dial and LCD electronic) are designed to utilize a rack & pinion for the dial to function. Even the slightest amount of foreign material (or a rapid movement of the slide) can cause the pinion to "jump" a tooth or more when sliding the movable jaw of the vernier. This will cause the readings to be completely incorrect. Most manufactures include a thin copper or brass shim that is designed to enable the operator to re-align and thus "zero" the gauge if used correctly.

The very cheap slide style vernier calipers that do not have the rack & pinion feature and thus will not "slip".

Most affordable Vernier calipers can not easily determine measurements in the .0001.

For What It's Worth:

A lifetime ago (1963-1973) I worked for the Department Of Defense at San Francisco Naval Shipyard. Because of the inherent inaccuracy of vernier calipers, they were "Banned" from use at that facility. If found the operator could be "written up". All precision measuring instruments had to be re-calibrated at least every three months.

During the same period, the government purchased many Mitutoya micrometers. They would NOT hold accuracy as purchased. The metrology lab found that if the threaded portion in the barrel of the mikes were lapped with a very fine compound, they then would work well and could maintain the accuracy required between re-calibration periods. To the best of my knowledge this has long since been corrected by Mitutoya.

"Snap" gauges and telescope gauges are the same thing and have no readable marks on them. An O.D. mike is usually used to get a reading off them.

Inside mikes are precision measuring instruments and some are marked to be able to read in .0001. Most are marked to read in .001.

Intra mikes (tri-mikes) can be read directly and because of the three points of contact are giving an excellent "average" diameter.

Regardless of whether the instruments are calibrated or not, a comparative reading can still be made for mating parts.

i.e. Take a reading of any bore using any measuring devise. (telescope gauge, inside mike). Using an O.D. mike measure to get a reading and record that figure. Using the same O.D. mike, measure whatever is going into that bore. Record that reading. Assuming the reading for the bore diameter is greater than the O.D. of whatever is going into that bore, the difference is the total clearance between the two parts. This will give a comparative reading even if the calibration is off.

I added some photos for viewing of the various measuring instruments I refer to. The first is a dial bore gage, followed by a dial vernier caliper, intra-mike (tri-mikes), O.D. mike and then telescope gage (sometimes called a snap gage).
Attached Thumbnails
Click image for larger version

Name:	dial bore gage.jpg
Views:	128
Size:	3.2 KB
ID:	39495   Click image for larger version

Name:	dial vernier caliper.jpg
Views:	106
Size:	6.2 KB
ID:	39496   Click image for larger version

Name:	intra-mike.jpg
Views:	107
Size:	28.8 KB
ID:	39497   Click image for larger version

Name:	outside diameter mike.jpg
Views:	107
Size:	7.9 KB
ID:	39498   Click image for larger version

Name:	telescope gage.jpg
Views:	118
Size:	7.3 KB
ID:	39499  


Last edited by Frisco; 07-16-2009 at 09:31 AM. Reason: added photos for clarification
Reply With Quote Quick reply to this message
  #15 (permalink)  
Old 07-16-2009, 09:27 AM
Frisco's Avatar
Glad To Be Here
 
Last photo:
Join Date: Nov 2002
Location: Canton, North Carolina
Age: 72
Posts: 2,244
Wiki Edits: 0

Thanks: 0
Thanked 8 Times in 8 Posts
Added photo of inside mike set.
Attached Thumbnails
Click image for larger version

Name:	inside mike set.jpg
Views:	126
Size:	41.2 KB
ID:	39500  
Reply With Quote Quick reply to this message

Recent Garage - Tools posts with photos

Quick Reply
Message:
Options

Register Now

In order to be able to post messages on the Hot Rod Forum : Hotrodders Bulletin Board forums, you must first register.
Please enter your desired user name (usually not your first and last name), your email address and other required details in the form below.
User Name:
If you do not want to register, fill this field only and the name will be used as user name for your post.
Password
Please enter a password for your user account. Note that passwords are case-sensitive.
Password:
Confirm Password:
Email Address
Please enter a valid email address for yourself.
Email Address:

Log-in

Human Verification

In order to verify that you are a human and not a spam bot, please enter the answer into the following box below based on the instructions contained in the graphic.




Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
 
Thread Tools

Posting Rules
You may post new threads
You may post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are On



All times are GMT -6. The time now is 08:17 AM.


Powered by vBulletin® Version 3.8.7
Copyright ©2000 - 2014, vBulletin Solutions, Inc.
Search Engine Optimization by vBSEO 3.6.0 PL2
Copyright Hotrodders.com 1999 - 2012. All Rights Reserved.