Dial Gauge

[WolfieParticipant @wolfie]

Ok I was having trouble centreing things in my 4 jaw chuck so was advised to get a dial gauge.

 

I got one! Here it is.

 

 

Ok whats the second knob for. Doesn’t appear do do owt except undo and fall off I presume the two plastic bits are so you can split a difference ( I know what I mean).

And they didn’t send me anything to mount it on I was expecting a clip or summat. OK so how do I go about mounting it. I do have a metal block with post and scriber holder.

 

 

Edited By Wolfie on 27/10/2010 21:25:35

Edited By Wolfie on 27/10/2010 21:26:41

[WolfieParticipant @wolfie]

[wheeltapperParticipant @wheeltapper]

Hi

the second knob locks the outer ring with the numbers on it.

this allows you to set the zero mark anywhere on the clock.

 

all you need to mount it is a piece of threaded rod and a locking knob, the other end of the rod goes to a magnetic base or a short bar you can clamp in the toolholder.

 

Roy

[V8EngParticipant @v8eng]

Hi.

 

If you look at tool suppliers websites you will find magnetic bases with swivel adjusters to support your dial gauge, the choice available is very wide.

Or if you live within range, go to one of the upcoming exhibitons to see what’s available, and get good advice about all this into the bargain.

 

 

 

Edited By V8Eng on 27/10/2010 22:10:12

[John OlsenParticipant @johnolsen79199]

For use with the four jaw chuck a short piece of bar to fit the toolholder with a hole in the end to match the hole in the dial gauge is all that you need. Magnetic bases are more useful when you have large flat areas for tehm to stick to, like on a mill.

 

regards

John

[Peter G. ShawParticipant @peterg-shaw75338]

Well, I always thought that the second knob was actually an additional foot – an elephant foot I believe – which can be used to replace the existing “pointy” foot. On both of the gauges I have had, these two parts were interchangeable, and indeed they were interchangeable between the gauges, so I now have 4 feet for my remaining gauge.

 

As far as the two plastic bits are concerned, again, my understanding was that they are to designate limits, eg tolerance limits.

 

No doubt someone will now put me right, but, I do find it convenient sometimes to use the broad, elephant, foot on round work which is perhaps slightly rough. The gauge then gives a smoother reading, whereas the pointy foot bounces about all over the place.

 

Regards,

 

Peter G. Shaw

[wheeltapperParticipant @wheeltapper]

The one in the picture looks amazingly like those sold by screwfix, of which I just bought two.

 

the second knob does lock the dial but,  coincidentally, has the same thread as the foot.

 

so, it could be used as an elephants foot, but then the small foot doesn’t lock the dial.

 

swings and roundabouts.

 

Roy

[Richard ParsonsParticipant @richardparsons61721]

 

You do not need a ‘clock gauge’ to centre a 4 jaw chuck. One way I often use is with a bar in the tool post. How do you do it?. If the work piece is symmetrical you centre up roughly using the circles machined into the face of the chuck. Your jaws are in pairs. Say 1 & 3. First pair then 2 & 4. Set 1 facing you 3 is opposite you. Bring up the tool post with its bar (or tool)and wind it in until it just touches the work now set the setting circle to 0. Next move the tool post away from the chuck and rotate the chuck 180° so that 3 is facing you and 1 is opposite. Bring up the tool post and move the tool to touch the work and note the reading beware of ‘backlash’ and compensate for it if needed. Wind the tool post away from the chuck and adjust the position of the tool to half that distance. Bring the tool post back and adjust the 1&3 as required checking both sides. Now use that tool post setting to set up jaws 2&4. Now re-check everything. Repeating until you are satisfied.

If the thing is totally asymmetric or you wish to bore something eccentric mark out the centre you want to make a long armed wobbler. This is a length of straight rod about 1/8” diameter some 13” long (a bit of silver steel). Machine a nice point on each end. Get a bronze ball – about 3/8” dia- (they are advertised) drill it right through and locktite it about 1” from the one end of the pointed rod. Make a carrier from a bit of metal (I used alloy) drilling a hole across one end and countersinking it on both sides Drop the ball and rod into one side of the countersink and check the swing you have. It should be about 2” overall. Make up a cover plate and ‘habeas-corpus’. To use it chuck your work piece put your wobbler into the tool post short end to the chuck. Pop the point into centre mark and do the business of 1&3, 2&4. I usually put a centre into the tail stock to act as a guide. With a 10 to 1 (or there about) a 1thou run out will show up at the other end as 10 thou. This shows up well.

 

[Ian AbbottParticipant @ianabbott31222]

The two plastic pointy thingies would be to mark the high and low points of the needle travel.  Split a difference as you say.  

 

We don’t of course ever nudge the work over using the dial gauge foot…….  Yes, I have seen that done, just like the ones who use a hammer and chunk of wood to remove SU carb needles.

 

Ian 

[Peter G. ShawParticipant @peterg-shaw75338]

But why would you want to lock the dial? Surely there is enough friction to hold the dial in place without locking?

 

Peter G. Shaw

[wheeltapperParticipant @wheeltapper]

all I know is in the instructions the second knob is called an “outer bezel lock”

 

depends how much friction there is I suppose, I’ve got three different makes and they are all different, one is quite loose unless it’s locked.

 

If I could afford posh ones I guess I wouldn’t have to lock them.

 

Roy

[Anonymous]

All my dial indicators have bezels locks, and they’re not ‘cheap’ makes, so I don’t think it’s a quality thing. Probably more to do with if you want it locked, you want it locked and not able to move. If you’re using it for comparison purposes and it moved accidentally, leading you to make inaccurate parts I don’t suppose the boss would be sympathetic!

 

Regards,

 

Andrew

Edited By Andrew Johnston on 28/10/2010 21:59:11

[TomkParticipant @tomk39956]

The type of clock that Wolfie has purchased is the type that would have been used in a production inviroment on gauges. This type of clock was used on inspection gauges as a  go no go gauge. If you can imagine a compontent that has maybe be 3 or 4 dimension that must be within a certain tolerances. The gauge could have multi[ple clocks mounted on it. The gauge would be set by the inspector using a master component. The 2 movable plastic markers  would be set to the mininim and maximum sizes on each clock  otherwise the tolerance (e.g. +.010″ -.000″) 0r for metric (+0.24 mm -0.00mm).

The bezel would be then locked so that it could not move. The parts can then be put into the gauge by the operator or inspector and if all the needles fall within the 2 markers showing the tolerance that part would be passed as ok at a glance. Any clock neeedle outside the markers that part is scrap.

 

The only problem with using these clocks for truing work on a lathe is that an adapter is required if you want to true a bore other than this problem they do the job just as good as a finger clock.

 

[SpurryParticipant @spurry]

The gauge shown does look like the Screwfix one. They are selling the magnetic stand at special offer too – ref 51845 at £5.10 each. I just bought 4 to use for a suds guard on the mill.

 

Pete

[chris stephensParticipant @chrisstephens63393]

Does anybody remember the good old days when DTIs ( like Mercer or Baty) could be bought in boxes with some attachments, the most useful of which I find to be the right angle one. For those who have never seen one, it clips on the gauge and converts an ordinary gauge to a bore indicating or lever one. Just looked in the J&L catalogue and no show, shame.

 

Oh for the good old days. 

chriStephens 

Edited By chris stephens on 29/10/2010 00:14:42

[WolfieParticipant @wolfie]

“the second knob locks the outer ring with the numbers on it.

this allows you to set the zero mark anywhere on the clock.”

 

Do you mean the outer ring inside the glass?? 

 

I should mention that the pointers move INDEPENDANTLY of the ring around the outside held down by knob 2.

[Ian S CParticipant @iansc]

Chris, one of the first things I made after I got hold of a DTI was to make a right angle attachment.Ithink it was adapted from an artical in ME.  Ian S C

[jomacParticipant @jomac]

Hi again.

A good source for magnets to make the bases for dial gauges etc etc, is to take out the magnets from old radio speakers, grind off the spare bits of metal, and the if you are lucky you can drill and thread these new bases, also drop one in a plastic bag, to pick swarf or lost screws and nuts and bolts, invert the bag, remove magnet, find lost items then dump the rubbish, no dirty hands, or splinters.

It’s getting warmer and wetter here. John Holloway

[Nicholas FarrParticipant @nicholasfarr14254]

Hi Wolfie, the outer ring, or bezel which holds the glass and the the disc inside the glass with the 0 to 90 revolves around the body of the gauge. You can set it where you like and lock it so it doesn’t move by nudging or the like with the little knob.

 

Regards Nick.

[Ian S CParticipant @iansc]

Jomac,Another place to get suitable magnetsis theMagnetron from a micro wave oven, about 2″ dia X 1/2″ thick with a hole in the middle, very similar to a modern speaker magnet. Ian S C

[WALLACEParticipant @wallace]

I’m not sure about the magnet from a magnetron – they’re so powerful, you might not be able to shift it afterwards  !

 

 

w.

W

Edited By WALLACE on 29/10/2010 14:27:56

[WALLACEParticipant @wallace]

I’m not sure about the magnet from a magnotron – they’re so powerful, you might not be able to shift it afterwards  !

 

 

W

[wheeltapperParticipant @wheeltapper]

magnetron magnets aren’t that powerful, I got a pair of neodym ( I think thats how its spelt) magnets from a hard drive, only 30mm x 10mm x 2mm thick, I practically need a block and tackle to separate them.

 

Roy

[Anonymous]

I suspect your magnets are based on neodymium.

 

Regards,

 

Andrew

[wheeltapperParticipant @wheeltapper]

yea, that’s the animal.

 

nearly got it right,

 

whatever, the’re b****y powerful.

Roy

[Author]

Posts