# Mitutoyo 24" (600mm) Height Gauge



## GreatOldOne (Mar 17, 2016)

Guys,

I got this a couple of months ago, and it's a great bit of kit. It was a steal on eBay... But since getting it, I've realised its quite a bit taller than I need. With it sat on my surface plate, the pillars that the read head runs up and down on hit the roof of the shop, depending on where you park it. 




Here it is... And that's as far back as it'll go when the plate cover is on. 

Now - this may sound like complete blasphemy, and it's only an idea... But would it be feasible to cut 6 inches from the top of the gauge, giving it overall height of 18? I'm guessing that if it is possible, I'd need to remove the cap on the, top cut the rods (without bending or marring them) and then replace it. 

I can see that the top cap is held on with set screws. Removing them was easy - but it would app3ar that the cap is press fitted on as well, as it certainly doesn't want to come off.

I obviously don't want to bugger it up. And if the risk is to great, I'll live wth it as it is. This is more of a convenience thing. 

Thanks

Jason


----------



## ch2co (Mar 17, 2016)

What brand is it?  Man that thing is huge!  I would think twice (or even more) before cutting it down. Raise the ceiling! Anything! 
The preceding is just the opinion of a worn out old man.  But he thinks it is correct. 

CHuck the grumpy old guy


----------



## GreatOldOne (Mar 17, 2016)

It's a mitutoyo:













Image



__ GreatOldOne
__ Mar 17, 2016


















Image



__ GreatOldOne
__ Mar 17, 2016
__ 1


----------



## Bob Korves (Mar 17, 2016)

How about moving the surface plate to where the ceiling is taller?  That is a really tall height gage for that size surface plate.  You must do a lot of tall but skinny work!  8^)

I have a 18x24x4" AA surface plate and a 12" Starrett vernier height gage, and I am very happy with what I have.  So far I have never wished for anything taller, and have never needed to change the battery...


----------



## chips&more (Mar 17, 2016)

Offer it to someone on the HM. I’m sure somebody would take you up on it and find room in their shop. Then you can get a shorter one for yourself.


----------



## Holescreek (Mar 17, 2016)

The top cap is glued on the front post and the rear post is left to the setscrews for retention for calibration purposes.  Loosening the rear screws as you mist have probably already blew the cal.  You might as well heat the cap to soften the glue and have your way with it now then reattach the cap and figure out how to tecalibrate it.


----------



## Tony Wells (Mar 17, 2016)

I would have traded you an 18" for it. As it is, I have a bi-directional touch probe that should fit that thing that I never use if you end up keeping it.


----------



## TOOLMASTER (Mar 17, 2016)

cut it shorter


----------



## Silverbullet (Mar 18, 2016)

Why not cut out a section of the counter top and lower your surface plate so its even with the counter . Then you can make a cover and keep it clean and at easy access.?


----------



## GreatOldOne (Mar 18, 2016)

Well, I've bit the bullet. It's now 6 inches shorter. And can still play the piano.

I heated the end cap and that did soften the glue, and it popped off easily. I then cut the rods on the band saw, ensuring the rods where prevented from flexing in by using some parallels between them.

Once they been cut, it was a quick debur, clean out of the top cap and then it was put back on with some locktite






Checked with my gauge blocks - it's all still dead on. Result.


----------



## TOOLMASTER (Mar 18, 2016)

GREAT but you put it together upside down!!!!

do over!!

now the floor is to low.


----------



## ch2co (Mar 18, 2016)

EXCEPT its now upside down! everything is going to fall off on the floor. Now you've done it! 
Glad you solved your problem even if I find such modifications egregious.


----------



## P T Schram (Mar 18, 2016)

Sell it to me and buy a smaller one!


----------



## GreatOldOne (Mar 18, 2016)

ch2co said:


> EXCEPT its now upside down! everything is going to fall off on the floor. Now you've done it!
> Glad you solved your problem even if I find such modifications egregious.





TOOLMASTER said:


> GREAT but you put it together upside down!!!!
> 
> do over!!
> 
> now the floor is to low.



Doh! I must have had the camera set to Aussie mode. Is that any better?


----------



## Holescreek (Mar 18, 2016)

You don't calibrate it by checking the low end of the gauge, you need to check it at intervals for the entire height. Once you have the numbers on a chart you can see how much the difference grows or shrinks as you move up the scale. If the numbers grow further from nominal at the top you need to lean the rear bar back some and test again. If the numbers shrink you lean it forward.  The "leaning" is done by loosening the rear bar screws slightly (leaving them snug enough to keep the rear bar from slipping loose) ad use the wooden handle of a hammer to whack  either the front or  rear of the top cap in the direction it needs to go.  Then retighten the screws and inspect again.  

I give myself a 10 micron tolerance from the nominals on the Mitutoyo dual beam gauges.  If you just want a quick and dirty smell check  test it at top, middle and bottom to start with.


----------



## P T Schram (Mar 19, 2016)

Holescreek said:


> You don't calibrate it by checking the low end of the gauge, you need to check it at intervals for the entire height. Once you have the numbers on a chart you can see how much the difference grows or shrinks as you move up the scale. If the numbers grow further from nominal at the top you need to lean the rear bar back some and test again. If the numbers shrink you lean it forward.  The "leaning" is done by loosening the rear bar screws slightly (leaving them snug enough to keep the rear bar from slipping loose) ad use the wooden handle of a hammer to whack  either the front or  rear of the top cap in the direction it needs to go.  Then retighten the screws and inspect again.
> 
> I give myself a 10 micron tolerance from the nominals on the Mitutoyo dual beam gauges.  If you just want a quick and dirty smell check  test it at top, middle and bottom to start with.



This guy knows of what he speaks! Nice discussion.explanation.

IF one was overly punctilious, one could plot gage block dimension on the X axis and measured dimension on the Y axis and one would have something of a calibration chart that could be used to compensate for any systematic error-assuming the distribution of error is constant and not random.

And there you have it, your class on theoretical error measurement, corrections, and compensation in two posts.!


----------



## Holescreek (Mar 19, 2016)

I have found error at top, at bottom and only in the middle on some height gauges.  Mitutoyo used to have a sticker on the side of the top cap showing that you should never pick one up by lifting on that cap or squeezing the bars together.  What it didn't say was that buy doing that you could affect cal.   I used to have to maintain (calibrate) and repair 60+ of these dual beam Mits and in the last 10 years have only had a few that couldn't be repaired due to obsolete parts.


----------

