Dial Indicator

[EdK]

Tom beat me to it but I was going to suggest the same thing. A DTI first, then a DI. You don't need to spend an arm and a leg on those two. But don't get the bottom of the barrel either.

Ed

[Hopefuldave]

Also, a dial indicator (plunger type) is used for direct measurement - but the measurement has to be in line with the plunger - and gives a direct reading, a dial TEST indicator (finger type) is used  to indicate whether or not there's movement, and is only accurate on its dial with the finger at a precise angle to the movement. This isn't a problem for the normal uses (centring in the 4-jaw, aligning a vice with the mill's ways etc.) where you're looking for an absence of movement, but can fool you if you're looking for e.g. precisely offsetting a workpiece in a 4-jaw to cut an eccentric, or mapping a surface for scraping!

Dave H. (the other one)

[pepi]

Thanks for the help sorting out the terminology. Now having that a second indicator will be the DTI with more range. 

As you can see the one I have has a small range, I can make it work but it is tight.

[TomG]

Greg,

Plus/minus dial indicators like that are used for inspection on production parts, and aren't much good for general shop work. Your primary indicator should be a dial test indicator with .0005" divisions and a range of at least .020". The Interapid 312-B1 is what I use, but they are pricey at $250. Mitutoyo also makes pretty good indicators and for a lot less money. Their 513-402 fits the bill at $100.

I would not advise cheaping out on an indicator (the Chinese are not your friends). One that sticks or one that breaks the first time you bang it against the work isn't going to be your friend, especially if you scrap out a part because of it. The Interapid's are bullet proof and will last a lifetime. In fact, the one I am using today that I bought in the 80's was once launched across the shop by the mill (don't ask), and it still works as good as new. The Mitutoyo's not as much, but they are still good indicators.

Tom

[Mayhem]

(02-16-2016, 10:56 PM)TomG Wrote: Greg,

...The Interapid's are bullet proof and will last a lifetime. In fact, the one I am using today that I bought in the 80's was once launched across the shop by the mill (don't ask), and it still works as good as new...

Tom - you cannot post that and then say don't ask. I want details

[TomG]

I felt your ears perk up way up here Darren.

Got distracted by something and walked away from the mill. Came back on hit the go button about the same time I realized the indicator was still hanging on the spindle. Luck definitely does play a part in surviving this business because I ran the numbers and the indicator parted ways with the mill at about 130 mph. This was also quite a few years ago so it can't be blamed on senility, just a simple distraction. Now people are driving cars with cell phones in their hands.

Someone should man up and start a thread on this topic. I'm sure there are plenty of interesting stories out there.

Tom

[Highpower]

(02-17-2016, 08:45 AM)TomG Wrote: Someone should man up and start a thread on this topic. I'm sure there are plenty of interesting stories out there.

Tom

Does it have to involve indicators?

[pepi]

Tom,


Going to take the advise and get the Mitutoyo 513-402.

I did give this one a look, the reviews were not good, only 2. I realize that means nothing. However the problem stated was  about the case not having a good fit.
http://www.amazon.com/Starrett-Indicator...B00BB1AAUM
 The evil word out sourcing seems to be popping up in the same sentence and the name mentioned .... bothersome .

None of the DTIs have the counter wheel as does the Interapid. I am going to assume that will not be a big deal cause I have DRO on this mill.


Thanks

[EdK]

Nice choice Greg.

I'm a fan of Mitutoyo. Good value for the money.

Ed

[pepi]

Coil toss........if you are buying a DTI today,  (heads) vertical or (tails) horizontal, most friendly?