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Ian B
08-13-2003, 08:32 AM
Anyone out there have or use a centering indicator? http://www.rutlandtool.com/ have them on sale for $75, normally $125, see page 721 of their catalogue (no, I don't work for them, someone just dropped their catalogue on my desk...)

Having read the thread on optical centering scopes, I wondered if these are a (useful) alternative. They claim centering accuracy to 0.0002" of true center. Any thoughts?

TIA,

Ian

Ragarsed Raglan
08-13-2003, 09:36 AM
Ian,

I think the centering indicator you are refering to is more of a hole or boss pick up tool. For that purpose they are good, but for the money a good ole Starrett 'wiggler' is better!

The centering scope is unbeatable where you need to pick up a centre punched datum, or mark out scribe lines.

The cenering indicator, I can see, would be useful on the lathe as well as the mill so it does score some points on versatility.

At the end of the day it all depends what sort of work you are doing. For component 'marked out' work in either lathe 4 Jaw or Mill, and without a CNC capability, or a DRO then the centering scope gets my vote.

If your doing second operation work, repairs, or such like, then a centering indicator is a pretty useful piece of kit, not essential, and probably no better than a 'wiggler'.

RR

[This message has been edited by Ragarsed Raglan (edited 08-13-2003).]

JCHannum
08-13-2003, 10:22 AM
That centering indicator is a version of the Blake Biaxial centering indicator, and is very good for picking up center of a boss or hole as RR says. With centerpoint, it can pick up a center punch mark.
I have a Blake, and use it frequently. It is accurate for most HSM work, but scope is better for dead on applications.
In the mean time, I used the Rutland site to send for a free catalog.

Ian B
08-13-2003, 11:02 AM
That's the one, JC; they also have a pukka Blake indicator for $245.

Hadn't thought about using it in the lathe, but why not? With a 3/8" shank, it'll fit in a chuck. Handy for centring work to a centrepunch mark in a 4 jaw.

I'm getting more tempted...

Ian

JCHannum
08-13-2003, 12:31 PM
I highly recommend them for use in a milling machine, but a wiggler and indicator will be better for centering work in a 4 jaw chuck for much less money.
The Blake works best when you can use it in a rotating spindle to center the spindle over a stationary part.

debequem
08-13-2003, 02:11 PM
I had considered that for my mill, but I have a mill/drill and the quill travel is too short. Or, should I say, the indicator is too long.

Either way, I am going to use a centering scope where possible and a dial indicator or edge finder when I can't use the scope.

Ian B
08-13-2003, 05:38 PM
Length of the indicator; hadn't thought of that - good point. I guess the alternative is to wind the knee up the column (I have a turret mill) after centring the spindle. Not so good.

Thanks for that; maybe mounting the indicator directly into a purpose made taper adaptor, to keep it as short as possible would help.

Ian

brunneng
08-13-2003, 07:22 PM
I bought one of the cheap center indicators from Ebay $80.00 and for what I do as an HSM I just love the thing. It makes centering up on bore's so fast.

The smoothness and roundness of the bore does affect how close you can get to center. It jumps less from vibration due to roughness and a round bore is easier to read as a slightly out of round bore will never quite settle down.

I've also been looking at the scopes for punch marks and scribe work. I did get one of the optical center punches from Veritas<sp?> for approx $30. That's a great tool as well.

Thrud
08-14-2003, 01:57 AM
Ian
If you can afford the Blake - it is far smoother than the cheap imports. But as the other have said, the imports are probably just as functional. After all, we all can't be spoiled like RR and have a nice Centering Microscope!

Ian B
08-14-2003, 11:21 AM
Well, I've sent my $ off for the indicator (the Chaiwanese one, not a Blake); machining's a hobby for me, not a way of making a living, so I couldn't justify spending almost 4 times as much on a "proper" one.

I'll let you all know what it's like when I get to play with it. Thanks to all for the input guys; great stuff.

Ian