How do you measure outside of part?

[Per-Sev]

I have no experience with digital anything so if precisionworks says that they eat batteries then buy a Mitu. All my tool were Starrett I had inside outside mics, dial indicators, depth mics, height gages, gage blocks, calipers up to 24'' masters, pie tape, just about every tool Starrett made but they were all vernier scale reading. I would only buy used if you can try it out first don't buy used through ebay with a lot of people out of work you should be able to find some nice used tools for sale on Craigslist. Do you live in the US?

 

[Tom Anderson]

It depends on the diameter of the workpiece and the tolerances required, but I usually like using one of these.

Most of my electronic digital gages are Mitutoyo.

It's nice because they can do the math for you.

 

[precisionworks]

Most of my electronic digital gages are Mitutoyo.

Mine too. All the Mitu digitals take the same battery, and have used that same battery type for at least 10-15 years.

In fairness to Starrett, I just looked at their web site and they now state that the current Model 797 has >3500 hours battery life - identical to Mitu. Watch what model you buy & quiz the seller on batt life.

 

[tino_ale]

I have the solar panel 0-6" Mitutoyo caliper :nana:

 

[Tom Anderson]

Here's a photo of the gage drawer at my lathe:

I keep a variety of indicators, micrometers, and calipers handy. These are the ones I use most at the lathe. (I have drawers filled with other measuring tools elsewhere in the shop that I've acquired over the years based on various needs.)

Since so much of what I measure is 1.2" or less, the most used tool is the Mitutoyo Quickmike.

It has a non rotating spindle that moves .400" per revolution (based a glass scale measuring system )

I like it so much that I actually bought a back-up the other day. I'm a bit of a gage geek!

 

[KC2IXE]

Like that digital unimike

 

[mototraxtech]

Ok so I have decided that I will buy the two quantumikes in the 0-1 and 1-2 range from msc the next time they have a 40% or more sale. I would buy them now but I went racing last weekend and now I'm broke. Interesting thing the the older model mitu that look the same and are not quite as featured cost less retail but you get such a larger discount on the quantumikes that for both of the micrometers its only $15 more to get the new model. Thats when the same discount is added to both. Must mean they cost less to produce and they have a larger profit range. Interesting

 

[tino_ale]

Ok so I have decided that I will buy the two quantumikes in the 0-1 and 1-2 range from msc the next time they have a 40% or more sale.

I'm like you but haven't decided yet if the quick 2mm spindle feed is worth the extra bucks compared to the more classic 293-344 model.

I find the 293-344 mic for $125 new on ebay, sounds like a good price ?

 

[mototraxtech]

MSC is having a 40% sale today and the new quantumike is only $131.59
The older one with the same part number you listed is also only $102.20 sale only last two days though.

 

[tino_ale]

PM sent

 

[darkzero]

MSC is having a 40% sale today and the new quantumike is only $131.59

Thanks but I just happened to search ebay again last night & found one that was just listed. Sent my offer & got accepted for $120 brand new in box. Finally!

 

[wquiles]

Here is a better picture of the ID gauges that I use along with my Starrett caliper:

 

[cmacclel]

I use the same carbide jawed verniers that Will uses. I have a 1-3" set of Fowler Digi micrometers that I have never used. I have no problems accurately measuring parts (.001) mounted in the lathe chuck. It all comes with experience I guess

Mac

 

[precisionworks]

It all comes with experience I guess

+1

The reading on a mic is totally dependent on the pressure applied to the spindle, which is transmitted to the contact tip faces. Take a piece of ground stock like TGP shafting & mic it a dozen times - if the tip pressure is identical each time, the readings will all be the same. If some readings are too low or too high, keep working on technique until all readings are the same, or at least within +/- .0001".

I like the Mitu ratchet spindle & use it by clicking it three times for each & every reading. Some people don't trust a ratchet & prefer to rely on their fingertips, which can work better than any mechanical helper IF those fingertips have the experience to apply identical pressure each time.

 

[gadget_lover]

Click it three times? That's like a torque wrench, tightening till it clicks. I never thought of doing it that way. It makes perfect sense.

I have always done it the wrong way; spin the thimble till it touches and then spin the little knob through a few rotations. That's obviously the wrong way. I wish the instructions had mentioned the right way to use it.

Thanks!

Daniel

 

[darkzero]

Click it three times? That's like a torque wrench, tightening till it clicks. I never thought of doing it that way. It makes perfect sense.

I read about the three click method too & is what I do. A bit different from a torque wrench though. When I was a mechanic I was taught to stop after the first click. I've seen lots of other who click twice & sometimes I can see an extra bit of movement on that second click especially if oil or some type torque grease is not used. Well in my case I don't have clicks, I get beeps & vibrating so there's not mechanism to stop the wrench from overtightening.

 

[gadget_lover]

While it may seem obvious to some folks, the reading of the 1/10000 portion of a micrometer (from the vernier) takes a little practice till it becomes natural.

I found this set of javascript demos on the subject. One is for reading the main scales, the second for reading the vernier.

Main: ( to .001)
http://www.stefanelli.eng.br/webpage/en-dial-indicator-inch-graduation-001-in-simulator.html

Vernier ( to .0001 - ten thousandths)
http://www.stefanelli.eng.br/en/aka-micrometer-caliper-outside-inch-ten-thousandths.html

Daniel

 

[PEU]

I know it is a little bit "sacrilegious" but I did cut my larger inch/metric model to a more "handy" size/weight, and this is the one I now use like 90%+ of the time:

About $600-$1000 at retail, or as low as $25-$100 on eBay

Veeery nice vernier calipers, just searched ebay and not a single one available in the metric or metric/inch version (0-6" / 150mm) within Barry prices, I would purchase one for $25 anytime


Pablo

 

[wquiles]

I have bought and sold various of them, and I could never find a "good" one or "keeper" for $25 either. The better ones worth using seem to always sell closer to or slightly above $50, with prices closer to the $100 for the really nice, mint ones still in their original, fitted, wood boxes. New ones can still be found on Ebay, but I have yet to see one sell for less than $100 (again, for a new unit). Here we are talking about their standard length units (6" range) - longer ones are even more. Pricing here is for the more common/plain inch models (no letters after the 123). Metric models (M after the 123) do come up from time to time, but not as often.

The most rare of all, the "combined" inch/metric ones (EM after the 123) - those seem to always command the higher prices on Ebay. The only "gotcha" with those is that you can only do OD with those, since the top scale (normally used for ID) is measuring OD in Metric (you can still measure ID but you have to add the thickness of the nibs in your head instead of it being a direct measurement). The 12" 123EM model that I trimmed in the photo above is one of those rare English/Metric models, and the one I use most of the time. The 12" model is heavier, sturdy, with even larger/thicker bearing surfaces, and it is my favorite of them all. Although still heaver than regular dial/digital calipers, my 6" 123 master caliper still feels wimpy next to my "trimmed" 12" model :devil:

Quick intro to the No 123:
http://www.starrett.com/download/62_123_caliper.pdf


More details, with all of the available models:
http://www.starrett.com/download/246_p108_114.pdf

 

[PEU]

Thanks for the explanation Will, well... when I say 25 I can move a little over that too but in metric/metric, obviously im not in a hurry, if you guys see one let me know.

Trim this one http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=370278849123 to the size I want (and price it proportionally) and we are talking

Thanks