View Full Version : Dial Test Indicator (DTI) swivel clamp

15-10-2010, 11:38 AM
Hi, I'm looking for a dti to use with the mill and have found some with just the dial, and some that come with magnetic base clamps. I was thinking it would be useful to have one with some sort of swivel mechanism that can be mounted to a mill but don't know what they're called or where to find them. Everyone seems to be at the show this week so can't find much help either!


(images taken from here: http://www.chaski.com/homemachinist/viewtopic.php?f=4&t=83304&start=0)

Any recommendation of where to buy (dti and clamps) would also be useful.



15-10-2010, 11:52 AM
Have a butchers here.... http://www.arceurotrade.co.uk/Catalogue/Measurement/Dial-Gauges-DTIs they seem reasonable. your you could got for a more expensive one like a mitutoyo but that will cost you around 80

16-10-2010, 05:59 PM
What type of mill are you using? Vertical, horizontal, or universal?

If you're using a vertical mill, then the DTI in the foreground of your DTIHolder1 pic can be used in an ordinary 3 jaw drill chuck (assuming you have one) and is a sufficiently quick and accurate way of clocking a vice for example, or other work with a reasonably smooth datum edge - just don't, whatever you do, overtighten the chuck (I've seen people do all kinds of silly things like that). The chuck only needs a light grip on the clock holder.

If you are using a horizontal mill (ie, where the drive arbor / spindle lies horizontally), then a plunger type DTI on a magnetic base may be a better option (clamp the magnet to the machine body, with the plunger on the workpiece / vice parallel etc.

Hope that helps, just yell if you need clearer explanation, and I'll get back to you.

17-10-2010, 10:48 AM
Vikash, take a look here: http://www.engineering-supplies.com/sub/174/dtis-drop-clocks/
eg: http://www.engineering-supplies.com/product/5301/14-dia-straight-shank-clock-dti-holder/

I'm looking for something similar, I'll let you know if I find any more :)

19-10-2010, 12:42 PM
Thanks for the replies. I think a Coax indicator would be useful, something like this: http://www.machine-dro.co.uk/index.php?target=products&product_id=295

20-10-2010, 11:04 AM
Thanks for the replies. I realise what I was looking for now is called a coaxial indicator.

For ref, I have a Sieg X3 with chuck, and recently a rotary table.

I bought one of these from Allendale Electronics. I've pretty much discarded the Chinglish instructions and just having a play with it.
My only gripe so far is that it shows ~0.01mm movement without a probe attached. Is that a defect or to be expected?

20-10-2010, 09:54 PM
You turn the outside of the dial bezel to align up the zero mark.


20-10-2010, 10:41 PM
I mean it registers movement of ~0.1mm as the spindle turns. i.e attach the indicator to a chuck, don't attach a probe and switch the mill on low speed - the needle moves as much as 0.1mm as it revolves.

I'll have to check again, but I think the needle jumps at the same position during rotation, which I think is therefore a defect.

21-10-2010, 08:18 AM
Sorry about the misunderstanding.

Mine does exactly the same sort of thing, but once it is in use, it performs perfectly. I reckon I am well within 0.01mm, which is good enough for anyone except the purist.

Just one problem with them, when used with an RT with a chuck fitted, you very quickly run out of throat room. I have made some shorter probes which gives me about another 25mm or so to play with. They don't need to be super accurate as long as the touch point is nice and smooth when it is in use, it only ever uses a tiny portion of the probe tip, not the full circumference.

BTW, they are very good to use on the lathe as well, as a quickie check to see if your tailstock is in alignment. But you must first check to see that your chuck has zero runout.


21-10-2010, 01:59 PM
I spoke to the suppliers who said it's probably just at the top end of spec but they can replace it anyway.

For no real reason, here's a video of it :naughty: