# Digital Caliper to Height Gauge



## ozzie46 (Jan 8, 2009)

Hi all,

  I'm going to attempt to make 6 in digital caliper into an height gauge 
 per these plans. I will be using t6061 aluminum instead of the steel it calls for.
For my home shop I think the aluminum will be ok. 


 Ron  

View attachment Ht-Gage.pdf


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## mklotz (Jan 8, 2009)

I'll urge you to reconsider using aluminum for the base. It dings too easily and a burr on the base can easily cause errors in the measurement. Using aluminum for the scribe holder should be fine.

Two remarks...

Usually the bottom of the gage base is hollowed out - this to prevent rocking. You may want to think about doing that.

For accurate measurement, it's important that the caliper beam be perpendicular to the base plane. Give some thought to how you intend to achieve that once the parts are made.


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## ozzie46 (Jan 8, 2009)

Marv, 

  From reading your back post I have come to value your opinion highly. I will
try this out first and if it works out then I will make a proper base out of steel. :bow: 

 The ali is a little more forgiving when you are learning ;D. 

  I thank you for your input.


  Ron


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## mklotz (Jan 8, 2009)

You might be able to have the best of two worlds. Make the base from aluminum and then fit it with steel "horseshoes" thus simultaneously solving the base hollowing and dinging problems. 

Another, lesser, problem may be that, with a steel caliper and ali base, the tool may be a bit top heavy. A couple of lead plugs* will fix that.

Regardless, go ahead and build it. No matter what happens, you'll have gained some useful experience and that's what really counts.

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* Melting and pouring lead can be scary and dangerous. For small weighting jobs, I prefer lead shot. Any reloading supplier can sell you a bag of #5 bird shot. Pour it in the hole and seal with some epoxy. No heat required and no fumes to inhale.


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## ozzie46 (Jan 8, 2009)

Marv,

  I had thought about a steel plate on the bottom, but did not think of the "horseshoe" idea though. :wall: Good one!


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## T70MkIII (Jan 8, 2009)

Another great project idea! Thanks for posting.


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## Mike N (Jan 8, 2009)

Harbor Freight has a nice 12" Digital Height gage, some times its on sale for $ 79.00. I think it is great. I would rather build engines! Just a thought!


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## speakerme (Jan 8, 2009)

Hello,
I purchased a very useable and accurate new height gauge, dual beam, digital readout from eBay for just a little over $49. The shars one I had before it locked up one day, a became useless.

Best Wishes

Chuck M


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## T70MkIII (Jan 8, 2009)

Ozzie 46, I knew something was bugging me - the display will be upside down if you follow the plan. 

Can the reader/display be flipped on these? I don't have mine near to hand to try pulling it apart.


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## ozzie46 (Jan 9, 2009)

T70MkIII, 

  Actually the display will be on its side, reading from surface plate up. 

Mike N

  The digital calipers were iirc, $16 US at a HF plus no shipping. when your 
 on a pension every penny counts. :big: I enjoy building my own tools as much as building other things too. Doing this is teaching me ( I hope) to do my best at holding tolerances to close levels.  Then hopefully I will have a better chance at success when I build an engine. By the way ,anybody, what is a good first project in a steam engine? I have downloaded several plans from johntoms site but am not sure where to start.

 Chuck M

 I never seem to be able to win a bid on e-bay. I guess thats the reason I dont play poker or go to casinos.  ;D


 I thank you all for your comments and I consider them all. Please keep them coming as I have a lot to learn.


  Ron


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## T70MkIII (Jan 9, 2009)

ozzie46  said:
			
		

> T70MkIII,
> 
> Actually the display will be on its side, reading from surface plate up.



Silly me!


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## Mike N (Jan 9, 2009)

The problem with the cheap digital calipers from HF, you will go broke keeping batteries in them!  ???


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## Noitoen (Jan 9, 2009)

Mike N  said:
			
		

> The problem with the cheap digital calipers from HF, you will go broke keeping batteries in them! ???



Since building an height gauge involves building a base, you can always include a couple of AAA batteries  .These will keep the calipers running for years


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## baldrocker (Jan 9, 2009)

www.dealextreme.com for inexpensive digital calipers and
REALLY cheap bulk packs of batteries to suit.
BR


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## ozzie46 (Jan 9, 2009)

Here are some pics of build.

 I bought my first digital caliper from H/F about 4years ago, the batt went dead in about 6 mos. Went to Wally World (walmart) and got quality batteries and have not needed to replace them since that time.  Just my experience, don't know if it is typical.

 Do you think I need to cut off the scriber, aka 3/16 HSS tool blank?

 Ron


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## mklotz (Jan 9, 2009)

Your caliper batteries will last longer if you use the silver-oxide SR44 in lieu of the cheaper alkaline LR44. (The latter are often sold as a one-for-one replacement for the former but they aren't.)

Devices like the calipers raise the "replace battery" alert when the battery voltage falls below a certain value. Silver-oxide maintains its voltage to near end-of-life, then falls off rapidly while the alkaline's voltage drops steadily with use. Thus the alkaline will drop below the "replace battery" voltage earlier than will the silver-oxide.

There are many web sources for inexpensive SR44s. From this one,

http://www.sr44.com/

our club made a bulk purchase of 100 for $50, then sold them off to individual members in sticks of ten - one of the advantages of a local model engineering club. Absent the ability to justify such a large purpose, 25 for $16.50 is still a good deal - especially so if you have a fair number of electronic measurement instruments, most of which probably take this battery size.

[Aside: The cheap Chinese calipers never really turn off - they only disable the display. This helps to account for their battery hunger.]


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## T70MkIII (Jan 9, 2009)

Looks good, Ron.

I would guess no need to trim the scribe unless the whole lot becomes unstable with the scribe near the top. If this was the case, it looks like you could shorten the scribe and shorten the horizontal mounting block a bit to reduce the weight of the overhang.


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## BaronJ (Mar 26, 2014)

Hi Guys,

Thought you might like to see mine.


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## ddmckee54 (Mar 27, 2014)

Baron:

I love what you did to that poor caliper.  It looks like you put a lot of skull sweat into that masterpiece.  Could you show or at least describe the clamping bolt you are using for the jaw, give us a little more detail? 

Don


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## chucketn (Mar 27, 2014)

Ron, go for it.
I'm retired and on a fixed income. I built mine with an HF caliper, and a chunk of cast iron from a tractor weight. I made no modifications to the digital caliper, so if my regular one craps out I can remove this one and use it.


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## BaronJ (Mar 27, 2014)

ddmckee54 said:


> Baron:
> 
> I love what you did to that poor calliper.  It looks like you put a lot of skull sweat into that masterpiece.  Could you show or at least describe the clamping bolt you are using for the jaw, give us a little more detail?
> 
> Don




Hi Don,
Thanks for the compliments. 

The one thing I didn't think to take pictures of.  :wall::wall:
I do have more pictures if you want to see them though.

The clamping arrangement for the jaw consists of a short length of 6 mm silver steel slotted with a 3 mm thick slitting saw.

I threaded the end to take a nut that I had handy. M6X1 If I remember. I then put the rod into hole drilled into a piece of scrap about an inch long, slit down its length with a hacksaw.  Then I clamped it in the mill vice and slit it length wise, long enough to hold the cut off piece of the calliper jaw.  Unfortunately it needed a spacer, the short bit of 3 mm rod , to ensure that the jaw would contact the floor that the gauge was stood on.  The bottom end was filed so that it sat slightly below the edge of the lower jaw.

The original calliper was purchased from Aldi in Deauville in the Dordogne department of France a few years ago, whilst I was there on holiday for a mere 8.95 Euro.  Which is why it only reads mm.

The base is made from an off cut of cast iron bar about 3" in diameter with a slot cut into it just big enough to push fit the end of the calliper into it.  I cut a chunk out so I could drill an tap for a pair of 2Ba hex socket grub screws.

The calliper was modified by cutting off the inside measuring jaws and the fixed outside jaw, as can be seen one of them was used to make a scriber.
The depth measurement rod was also removed.  Actually it was so brittle that it simply broke off at the point where it was fastened.

The first picture in the last post shows a working hight gauge.  Subsequent pictures show further modifications made in order to be able to accurately set a specific hight.  Since I found that in use it was quite easy to lower the measuring head onto the work but very finicky to set a hight.

A last note, its important that the calliper column is exactly vertical in both directions.


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