# Mitutoyo Digimatic Micrometer - What Spindle ?



## LHC (Apr 24, 2014)

I want a Mitutoyo Digimatic series 293 electronic micrometer and I’m going to buy one.  It doesn’t matter if I actually need it a lot or not, I just want one, I’ve got some money and I’m going to have it.  There, now that we have that out of the way….

What spindle to get ?  I’m only familiar with ratchet stop mics, but I’m leaning towards the friction spindle for this one.  I’m not heavy handed and I sort of like the idea that there’s no “hammer action” with the friction spindle, but I have never used one, nor do I know anyone with one, so it’s going to be a leap of faith without hopefully some comments and words from those of you that have used them and your impressions of them.

To further add to the paralysis by analysis, Mitutoyo has a third option - “ratchet spindle” which is something different again – it looks from the literature on their site that it’s a ratchet without the little knob at the end of the spindle but they describe it as “audible operation provides confirmation of constant measuring force” whereas the ratchet stop is described as “Audible clicking operation causes micro-shocks”.  It seems to me that the mechanism with the ratchet thimble is more like a friction thimble with a little noise, rather that the classic hammer effect of the ratchet stop.  The friction spindle of course is described as “Smooth operation without shock or sound”.

Here are the three models I’m looking at - 

293-340 – Ratchet Stop
293-344 – Ratchet Thimble
293-348 – Friction Thimble

Has anyone on here tried out or used these various options and can enlighten me as to their impressions of them?   I was leaning towards the friction spindle, but the ratchet spindle has me entrigued now that I am reading Mitutoyo’s literature.  

I realize that any of them are going to be fine instruments and I can always ignore the force limiting feature and go by feel, but I’d like to learn about the relative merits / impressions of the three force limiting features above.

Thanks !


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## rmack898 (Apr 24, 2014)

I think it is more of a personal preference thing than anything else. 

When I was being taught to read a mic many years ago I learned with a friction thimble Starrett that I still have. My go to mic these days is a friction thimble Mitoyo diigimatic. It is extremely smooth and feels good in your hand. I don't think you will be unhappy with any of your choices


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## JimDawson (Apr 24, 2014)

My personal preference is the friction thimble.  I always felt that the ratchet type feel a lot like an impact wrench.  Normally I just "drag" my finger across the thimble to get the correct tightness, it is rare that I actually grab the thimble to turn it.  You will be happy with any of the above in any case.


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## LHC (Apr 25, 2014)

Thanks for the feedback fellows.  
I'm going to go with the friction thimble, but as both of you have said, I would probably be happy with whatever one I went with.


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## Bill Gruby (Apr 25, 2014)

You won't be sorry. The feel is positive. I also use the Friction Thimble.

 "Billy G"


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## LHC (Apr 25, 2014)

Bill Gruby said:


> You won't be sorry. The feel is positive. I also use the Friction Thimble.
> 
> "Billy G"



If it's good for Bill, it's good for me !   
Thanks !
Lewis


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## tertiaryjim (Apr 25, 2014)

Friction thimble, Good choice!
Too many people will crank a ratchet through 30 clicks because they can't get a good feel and stress the mic out a few tenths.
You will have to develop your feel with a friction thimble but that just takes time and practice.


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## LHC (Apr 25, 2014)

It's ordered !  Good old Amazon.  
Now I can eagerly check the shipping status every 1/2 hour with much excitement.....


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## LHC (Jun 25, 2014)

LHC said:


> It's ordered !  Good old Amazon.
> Now I can eagerly check the shipping status every 1/2 hour with much excitement.....



Thought I'd post up a little follow up on this.  I have been using the unit for a few weeks now off and on.  I'm trying to bring an old lathe back to life and have it stripped to the last fastener, and have been starting to measure and check things.  The micrometer is fantastic, and it's hard to put into words how it feels when turning the spindle and feeling it start to friction slip, but it does reek of quality.  I'm very happy with my purchase and would buy it again in a heartbeat.  If anyone is thinking about one of these and is on the fence, this hopefully will be the nudge to push you off and get one.

I've been using it in a little panavice as it's easier for me to check parts that way, but I can see that with a bit of practice, holding it in one hand and positioning the parts with the other should be no problem.  The spindle having the force limiting device allows you to rely on the limiter with a one handed operation whereas if the device was on the end of the spindle (like a ratchet stop version) it would be all but impossible....at least with the size of my hands.

My next purchase is going to be a 1-2"mic but I am torn once again between going old school or with the digital one.  Mitutoyo does not seem to offer the digimatic in a 1-2" with a friction thimble and no output connector, and the one that they do offer is a bit stiff in price - closing in on 300 bucks.  There is a ratchet thimble version though so that's an option and would allow for one handed operation as well.  

Anyway, thanks again for the advice - I'm very pleased with my new toy - er tool.....

Lewis


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## hvontres (Jun 25, 2014)

I would vote for the digital one. I have a 0-1 and 1-2 Mitutoyo and a Fowler 2-3", all from e-bay. There are two features that make a digital mike much more valuable to me:

1) They are "bi-lingual". I have gotten used to designing in metric units but I couldn't afford a set of metric machines (my mill does have a DRO, something I will probably add to the lathe at some point). By having digital mics and calipers, I only need one set of measuring tools to check either type of dimensions.

2) I really like the ability of a digital mic to be set to the desired dimension and zeroed out. That way, I can check a diameter on the lathe and read the ammount of material left directly. This really helps avoid silly math errors, especialy when trying to hit a metric diameter using inch dials.

I hope this helps


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## PatMiles (Sep 7, 2014)

hvontres said:


> 2) I really like the ability of a digital mic to be set to the desired dimension and zeroed out. That way, I can check a diameter on the lathe and read the ammount of material left directly. This really helps avoid silly math errors, especialy when trying to hit a metric diameter using inch dials.
> 
> I hope this helps



Reading this point was a DUH! moment for me! Makes all the sense in the world. Why didn't think of that?????
Pat


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